Reduction Of CD4 Research Articles

Abstract P3086: Aldose Reductase Deletion Protects Ischemic Murine Hearts By Modulating Immune Cell Dynamics

Cardiac injury remains a major cause of death worldwide. Previous studies have demonstrated that chronic unchecked inflammation, during post ischemic reperfusion, adversely affects adaptive repair and augments tissue damage. Nature of the infiltrating immune cells determines the extent of repair vs exacerbation of tissue damage during post myocardial ischemia. Understanding mechanisms by which ischemia-mediated inflammatory responses exacerbate tissue damage and mitigate repair pathways are vital to discover therapeutics for myocardial infarction. Our earlier studies demonstrated that aldose reductase (AR) is a key mediator of myocardial ischemia-reperfusion (I/R) injury. Specifically, it established that cardio myocyte AR drives metabolic and signalling mechanisms leads to injury and impaired function in hearts. In this study we investigated the role of AR in influencing time dependent changes in recruitment of immune cells, during in vivo myocardial I/R injury. AR knockout (ARKO) and littermate controls (WT) mice were subjected to LAD sugery followed by reperfusion ( In vivo I/R) and the temporal changes in recruitment of immune cells were determined at earlier (day 3) and later (day 7) time points. We found ablation of AR leads to significant (p<0.0001) cardiac protection during post I/R in mice. Cardiac function measurements revealed greater recovery of ejection fraction and fractional shortening after I/R in ARKO vs WT hearts (p<0.05). Deletion of AR leads to a significant (p =0.0053) reduction in T cells infiltration post I/R in the heart. We observed 2-fold reduction in CD8+ cells, and 2-fold increase in CD4+ cells in ARKO vs WT mice hearts post I/R injury. Specifically, 2-fold reduction in pro-inflammatory Th1, Th2 and Th17 cells and 3-fold increases in anti-inflammatory Treg cells (p = 0.0091) were observed in ARKO vs WT hearts at post I/R injury. In addition, we observed reduction in infiltration of pro-inflammatory macrophages, dendritic cells, and B cells in ARKO vs WT hearts post I/R. Taken together, our data suggests that deletion of AR protects I/R hearts by promoting increases in anti-inflammatory immune cells and paves the way for addressing immune cell-cardiomyocyte crosstalk mechanisms by which AR deletion protects from I/R injury.

Efficacy of Targeted Mast Cell Inhibition Therapy in Chronic Prostatitis/Chronic Pelvic Pain Syndrome

To identify a subgroup of patients with mast cell dysfunction in chronic prostatitis/chronic pelvic pain syndrome and evaluate efficacy of mast cell-directed therapy. Men with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) were recruited and evaluated in an open-label, interventional uncontrolled trial after therapy with cromolyn sodium and cetirizine hydrochloride. The primary endpoint was a change in mast cell tryptase concentrations after treatment while secondary endpoints were changes in the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) and AUA-SI. Isolated cells from postprostatic massage urine were evaluated for immune changes using mRNA expression analysis. 31 patients with a diagnoses of Category III CP/CPPS were consented, 25 patients qualified and 20 completed the study after meeting a prespecified threshold for active tryptase in expressed prostatic secretions. After treatment with cromolyn sodium and cetirizine dihydrochloride for 3-week, active tryptase concentrations were significantly reduced from 49.03±14.05 ug/mL to 25.49±5.48 ug/mL (P<.05). The NIH-CPSI total score was reduced with a mean difference of 5.2±1 along with reduction in the pain, urinary and quality of life subscores (P<.001). A reduction in the AUA-SI was observed following treatment (P<.05). NanoString mRNA analysis of isolated cells revealed downregulation of immune-related pathways including Th1 and Th17 T cell differentiation and TLR signaling. Marked reduction in CD45+ cells and specifically macrophages and neutrophil abundance was observed. Identification of CP/CPPS patients with mast cell dysfunction may be achieved using tryptase as a discriminating biomarker. Mast cell-directed therapy in this targeted subgroup may be effective in reducing symptoms and modulating the immune inflammatory environment.

The effect of mogamulizumab on the aberrant Tcell population in the peripheral blood - A monocentric retrospective analysis.

The effect of mogamulizumab in cutaneous T-cell lymphoma (CTCL) on Tcells (TC) in the peripheral blood and its potential role to navigate treatment intervals are explored. We investigated within a retrospective monocentric analysis the effect of mogamulizumab on the CD3+ TC and the aberrant Tcell population (TCP), i.e., the CD4+ /CD7- and the CD4+ /CD26- TC, analyzed by flow cytometry. Thirteen patients with CTCL were included. After four cycles there was a mean reduction of 57% in CD3+ TC, 72% in the CD4+ /CD7- and 75% in the CD4+ /CD26- TCP compared to the individual baseline of each patient. The reduction in CD4+ /CD7+ and CD4+ /CD26+ TC was lower, averaging 54% and 41%. A significant decrease in aberrant TCP was already evident after the first administration. A median plateau of TCP already occurred during the IP. Progressive disease occurred in 5/13 patients without a clear correlation to aberrant TCP. Already after one dose of mogamulizumab, aberrant TCP and, to a lesser extent, normal TC decrease. We did not observe a clear correlation between TCP and the efficacy of mogamulizumab, but further studies with larger numbers of patients are needed.

Predictive effect of the decline in CD4+ T cell levels in blood on infection in patients with severe hemorrhagic stroke and mechanism

Objective The purpose of this research was to evaluate the influence of immunity on infection in patients with severe hemorrhagic stroke and explore the mechanism underlying this connection. Methods Clinical data obtained from 126 patients with severe hemorrhagic stroke were retrospectively analyzed, and the factors affecting infection were screened by multivariable logistic regression models. Nomograms, calibration curves, the Hosmer–Lemeshow goodness-of-fit test, and decision curve analysis were used to examine the effectiveness of the models in evaluating infection. The mechanism underlying the reduction in CD4 + T-cell levels in blood was explored by analysis of lymphocyte subsets and cytokines in cerebrospinal fluid (CSF) and blood. Results The results showed that CD4 + T-cell levels of &amp;lt;300/μL was an independent risk factor for early infection. The models for multivariable logistic regression involving the CD4 + T-cell levels and other influencing factors had good applicability and effectiveness in evaluating early infection. CD4 + T-cell levels decreased in blood but increased in CSF. Similarly, interleukin (IL)-6 and IL-8 levels in CSF had a significant increase, generating a substantial concentration gradient between the CSF and the blood. Conclusion Reduced blood CD4 + T-cell counts among patients who had severe hemorrhagic stroke increased the risk of early infection. CSF IL-6 and IL-8 may be involved in inducing the migration of CD4 + T cells into the CSF and decreasing blood CD4 + T-cell levels.

Circulating and Intratumoral Immune Determinants of Response to Atezolizumab plus Bevacizumab in Patients with Variant Histology or Sarcomatoid Renal Cell Carcinoma.

Renal cell carcinoma (RCC) of variant histology comprises approximately 20% of kidney cancer diagnoses, yet the optimal therapy for these patients and the factors that impact immunotherapy response remain largely unknown. To better understand the determinants of immunotherapy response in this population, we characterized blood- and tissue-based immune markers for patients with variant histology RCC, or any RCC histology with sarcomatoid differentiation, enrolled in a phase II clinical trial of atezolizumab and bevacizumab. Baseline circulating (plasma) inflammatory cytokines were highly correlated with one another, forming an "inflammatory module" that was increased in International Metastatic RCC Database Consortium poor-risk patients and was associated with worse progression-free survival (PFS; P = 0.028). At baseline, an elevated circulating vascular endothelial growth factor A (VEGF-A) level was associated with a lack of response (P = 0.03) and worse PFS (P = 0.021). However, a larger increase in on-treatment levels of circulating VEGF-A was associated with clinical benefit (P = 0.01) and improved overall survival (P = 0.0058). Among peripheral immune cell populations, an on-treatment decrease in circulating PD-L1+ T cells was associated with improved outcomes, with a reduction in CD4+PD-L1+ [HR, 0.62; 95% confidence interval (CI), 0.49-0.91; P = 0.016] and CD8+PD-L1+ T cells (HR, 0.59; 95% CI, 0.39-0.87; P = 0.009) correlated with improved PFS. Within the tumor itself, a higher percentage of terminally exhausted (PD-1+ and either TIM-3+ or LAG-3+) CD8+ T cells was associated with worse PFS (P = 0.028). Overall, these findings support the value of tumor and blood-based immune assessments in determining therapeutic benefit for patients with RCC receiving atezolizumab plus bevacizumab and provide a foundation for future biomarker studies for patients with variant histology RCC receiving immunotherapy-based combinations.

Immune landscape of patients with metastatic non-clear cell renal cell carcinoma (nccRCC) treated with atezolizumab plus bevacizumab.

4535 Background: The treatment of metastatic nccRCC remains an area of unmet clinical need. A multicenter phase II trial of atezolizumab/bevacizumab in patients with advanced nccRCC or any RCC type with ≥ 20% sarcomatoid differentiation (NCT02724878) demonstrated clinical activity of these agents, with objective response rates of 50% in patients with sarcomatoid clear-cell RCC (sccRCC) and 26% in patients with nccRCC. We aim to understand the intratumoral and circulating factors that impact immunotherapy response in this population. Methods: We collected blood samples prior to therapy and on-treatment (following 2 cycles of therapy) and quantified levels of plasma soluble factors (cytokines and growth factors) using a fluorescent bead array platform. We used high dimensional flow cytometry on peripheral blood mononuclear cells to analyze the composition and phenotype of peripheral immune cells. Immunohistochemistry and immunofluorescence were performed on available formalin-fixed, paraffin-embedded tumor tissue samples (archival or on-study biopsy) collected prior to the start of therapy. We assessed relationships between biomarkers and outcomes using pairwise Wilcoxon rank-sum test and log-rank tests, and univariate Cox regression models. Results: We collected blood samples from 60 patients with paired tumor samples from 38 patients. Baseline circulating inflammatory cytokines MIP-1b, IL-1, MCP-1, IL-6, and IL-13 were highly correlated with one another, forming an “inflammatory module” that was increased in IMDC-poor risk patients and associated with worse progression-free survival (PFS) (p = 0.028). At baseline, elevated circulating VEGF-A was associated with a lack of response (p=0.03) and worse PFS (p=0.021). Whereas a larger increase in on-treatment levels of circulating VEGF-A was associated with clinical benefit as defined by Braun et al. (Nat Med. 2020) (p=0.01) and improved overall survival (p=0.006). Among peripheral immune cell populations, an on-treatment decrease in circulating PD-L1+ T cells was associated with improved outcomes: reductions in CD4+ PD-L1+ (HR:0.62[0.49-0.91], p=0.016) and CD8+ PD-L1+ T cells (HR:0.59[0.39-0.87], p=0.009) correlated with improved PFS. Within the tumor, a higher percentage of terminally exhausted (PD-1+, TIM-3+ and/or LAG-3+) CD8+ T cells at baseline was associated with worse PFS (p=0.028). Conclusions: Among patients with advanced nccRCC or sccRCC, a baseline high systemic inflammatory state and high circulating VEGF-A are associated with worse outcomes after treatment with atezolizumab and bevacizumab. High levels of intratumor terminally exhausted CD8+ T cells were associated with worse PFS. These results highlight the importance of an integrative approach to explore biomarkers of response in advanced variant histology RCC which may inform future therapeutic approaches.

Expression of PD-L1 and VISTA in Intraductal Papillary Mucinous Neoplasm With Associated Invasive Carcinoma of the Pancreas

Early detection and treatment of invasive carcinoma arising in association with intraductal papillary mucinous neoplasm (IPMN), which is biologically and (epi)genetically distinct from conventional pancreatic ductal adenocarcinoma, provide an opportunity to improve the prognosis of this lethal disease. Despite the successful application of programmed death (ligand) 1 (PD-[L]1)-blocking strategies in numerous cancers, the immune microenvironment of IPMN with associated invasive carcinoma remains elusive. Here, we investigated CD8+ T cells, CD68+ macrophages, PD-L1, and V-domain immunoglobulin suppressor of T-cell activation (VISTA) in 60 patients with IPMN with associated invasive carcinoma using immunohistochemistry, explored their correlations with clinicopathologic variables and prognosis, and compared them with those in 76 patients with IPMN without invasive carcinoma (60 low-grade and 16 high-grade lesions). Using antibodies against CD8, CD68, and VISTA, we evaluated tumor-infiltrating immune cells in 5 high-power fields (×400) and calculated the corresponding mean counts. PD-L1 with a combined positive score of ≥1 was regarded as positive, and VISTA expression on tumor cells (TCs) was deemed positive when ≥1% of TCs showed membranous/cytoplasmic staining. A reduction of CD8+ T cells and an increase of macrophages were observed during carcinogenesis. Positive PD-L1 combined positive score and VISTA expression on TCs were 13% and 11% in the intraductal component of IPMN with associated invasive carcinoma, 15% and 12% in the associated invasive carcinoma, and 6% and 4% in IPMN without an invasive carcinoma, respectively. Interestingly, the PD-L1 positivity rate was the highest in a subset of associated invasive carcinomas (predominantly gastric-type-derived) and was associated with higher counts of CD8+ T cells, macrophages, and VISTA+ immune cells. Accumulation of VISTA+ immune cells was observed in the intraductal component of IPMN with associated invasive carcinoma compared with that of low-grade IPMN, whereas in intestinal-type IPMN with associated invasive carcinoma, the number of these cells decreased during the transition from the intraductal component to the associated invasive carcinoma. Survival analysis revealed that a higher number of macrophages predicted poorer prognosis. In conclusion, our results might help in individualized immunotherapeutic strategies for these patients.

Indeterminate results of interferon gamma release assays in the screening of latent tuberculosis infection: a systematic review and meta-analysis.

We aimed to evaluate the indeterminate rate of interferon gamma release assays (IGRAs) in the detection of latent tuberculosis infection (LTBI). On 15 November 2022, we searched the PubMed® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), and Cochrane Library databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two investigators independently extracted the study data and assessed their quality using a modified quality assessment of diagnostic accuracy studies (i.e., QUADAS-2) tool. A random-effects model was used to calculate pooled results. We included 403 studies involving 486,886 individuals and found that the pooled indeterminate rate was 3.9% (95% CI 3.5%-4.2%). The pooled indeterminate rate for QuantiFERON®-TB (QFT) was similar to that for T-SPOT®.TB (T-SPOT) [odds ratio (OR)=0.88, 95% CI 0.59-1.32]; however, the indeterminate rate for a new generation of QFT (QFT-plus) was lower than that of T-SPOT (OR=0.24, 95% CI 0.16-0.35). The indeterminate rate in the immunocompromised population was significantly higher than that in healthy controls (OR=3.51, 95% CI 2.11-5.82), and it increased with the reduction of CD4+ cell count in HIV-positive patients. Children's pooled indeterminate rates (OR=2.56, 95% CI 1.79-3.57) were significantly higher than those of adults, and the rates increased as the children's age decreased. On average, 1 in 26 tests yields indeterminate IGRA results in LTBI screening. The use of advanced versions of the QuantiFERON-TB assay (QFT-plus), may potentially reduce the occurrence of an indeterminate result. Our study emphasizes the high risk of immunosuppression and young age in relation to indeterminate IGRA, which should receive more attention in the management of LTBI. PROSPERO https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020211363, CRD42020211363.

Early peripheral blood lymphocyte subsets and cytokines in predicting the severity of influenza B virus pneumonia in children.

Children with influenza B virus infection have a higher susceptibility and higher severity of illness. The activation and disorder of immune function play an important role in the severity of influenza virus infection. This study aims to investigate whether early lymphocyte count and cytokines can provide predictive value for the progression in children with influenza B virus pneumonia. A retrospective cohort study was conducted to analyze the clinical data of children with influenza B virus pneumonia from December 1, 2021, to March 31, 2022, in the National Children's Regional Medical Center (Shengjing Hospital of China Medical University). According to the severity of the disease, the children were divided into a mild group and a severe group, and the clinical characteristics, routine laboratory examination, lymphocyte subsets, and cytokines were compared. A total of 93 children with influenza B virus pneumonia were enrolled, including 70 cases in the mild group and 23 cases in the severe group. Univariate analysis showed that drowsiness, dyspnea, white blood cell (WBC), lymphocytes, monocytes, procalcitonin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), fibrinogen (FIB), Immunoglobulin M (IgM), lung consolidation, total T cell count, CD4+ T cell count, CD8+ T cell count, NK cell count, NK cell % and B cell % had statistical differences between the mild and severe groups (P<0.05). In multivariate logistic regression analysis, reduced ALT (OR = 1.016), FIB (OR = 0.233), CD8+ T cell count (OR = 0.993) and NK cell count (OR = 0.987) were independently associated with the development of severe influenza B virus pneumonia. The levels of T lymphocytes and NK cells were related to the progression of influenza B virus pneumonia in children, and the reduction of CD8+ T cell count and NK cell count can be used as independent risk factors for predicting the severity of influenza B virus pneumonia.

Heterozygous TCF3-Related Disease Presenting as X-linked Agammaglobulinemia Mimicry in a Male Toddler with B-cell Aplasia, Agammaglobulinemia, and Severe Neutropenia

IntroductionDisease associated with TCF3 variants are rare and associated with autosomal dominant inheritance agammaglobulinemia. Patients present with profound reduction in CD19+ cells and a block in B cell development at the common lymphoid precursor to pro–B cell phase of differentiation. Severe neutropenia is frequently described in X-linked agammaglobulinemia (XLA) patients but not yet described as a presenting finding in TCF3-related disease. Case ReportThis case describes a 13-month-old full term male with a history of reactive airway disease and recurrent infections including multiple bouts of acute otitis media, hand -foot-mouth, and viral upper respiratory illnesses who presented with fever and persistent severe neutropenia (absolute neutrophil count <100 cell/uL) necessitating hospital admission. Given his infectious history and severe neutropenia, he underwent evaluation for an underlying inborn error of immunity with the following pertinent findings: undetectable IgG (<16 mg/dL), IgM (<10 mg/dL), IgA (<2 mg/dL) and IgE (<2 kU/L), negative pneumococcal, tetanus and diphtheria vaccine titers despite vaccination, lymphocyte subsets with normal CD3, CD4, CD8, and CD16/56 absolute values but extremely low CD19 level (38 cells/cmm), and negative anti-neutrophil antibodies. Patient Bruton tyrosine kinase (Btk) protein flow cytometry results in monocytes were similar to an experimental control, while B-cell subset analysis was unable to be obtained given low B-cell numbers. Comprehensive genetic testing subsequently identified a heterozygous pathogenic TCF3 variant, c.1663G>A, p. (Glu555Lys). Following initiation of intravenous immunoglobulin (IVIG) replacement, our patient's neutropenia resolved quickly and completely. He continues to receive monthly IVIG with goal IgG troughs >800 mg/dL and resultant significant improvement in infections. ConclusionAs in XLA, our patient's severe neutropenia rapidly resolved with initiation of immunoglobulin replacement. While it has been shown that neutrophil development is somewhat dependent on the Btk protein, further study into the importance of the TCF3 protein and additionally adequate immunoglobulin levels in neutrophil expansion is needed. Finally, germline inborn errors of immunity, including TCF3 variants, should be considered in children with a history of recurrent infections and persistent neutropenia.

Dysregulation of circulating MAIT cell subsets in patients with hidradenitis suppurativa

Abstract Hidradenitis suppurativa (HS) is a chronic inflammatory condition characterized by painful and debilitating skin lesions. Recent reports purport HS as an autoinflammatory keratinization disease with numerous pathways and features of systemic inflammation however few studies have been conducting to characterize peripheral immune dysregulation. Mucosal associated invariant T (MAIT) cells are an invariant T cell subset responding directly to bacterial threats and their dysregulation contributes to the pathogenesis of autoimmune disorders, cancers and inflammatory skin conditions. Here, we analyzed MAIT cells in the blood of 16 HS patients and 12 healthy controls (HC) by flow cytometry. We found that the frequency of MAIT cells did not change in HS patients, but their function changed drastically. We observed a significant reduction in the frequency of IFNy+ and TNFα+ MAIT cells in the periphery of HS patients. Furthermore, we analyzed MAIT cell subsets by their CD4 surface expression. Here, we found that the frequency of CD4+MAIT cells in the periphery of HS patients is significantly increased, while the frequency of CD4-MAIT cells is significantly decreased. Furthermore, HS patients have a reduction in CD4− IFNg+ and TNFa+ MAIT cells. Overall, these findings suggest that peripheral MAIT cells are dysregulated in HS patients which may contribute to the pathogenesis of the disease. NIH/NIAMS (1R21AR079089 and 1R01AR078688) for Dr. Mi and Henry Ford Immunology Program grant (T71017 for Dr. Mi and T71016 for Di Zhou).

Immunological Signatures Associated With Ocrelizumab Treatment in Early RRMS: 12-Month Interim Analysis From the Ocrelizumab Phase IIIb (ENSEMBLE; NCT03085810) Immunological Substudy (S16.003)

Immunological Signatures Associated With Ocrelizumab Treatment in Early RRMS: 12-Month Interim Analysis From the Ocrelizumab Phase IIIb (ENSEMBLE; NCT03085810) Immunological Substudy (S16.003)

Characterization of lymphocyte subsets and intestinal short-chain fatty acids in benzene-induced immunosuppressive mice.

Exposure to benzene causes immunosuppression, but the mechanism has not been clarified. In this study, mice were subcutaneously injected with different concentrations (0, 6, 30 and 150 mg/kg) of benzene for four weeks. The lymphocytes of bone marrow (BM), spleen and peripheral blood (PB) and the level of short-chain fatty acids (SCFAs) in mouse intestine were measured. The results showed that benzene exposure led to a reduction in CD3+ and CD8+ lymphocytes in mouse BM, spleen and PB, and CD4+ lymphocytes were increased in mouse spleen but decreased in mouse BM and PB after 150 mg/kg benzene exposure. In addition, Pro-B lymphocytes were reduced in mouse BM in the 6 mg/kg group. Besides, the levels of IgA, IgG, IgM, IL-2, IL-4, IL-6, IL-17a, TNF-α and IFN-γ in mouse serum were reduced after benzene exposure. Furthermore, the levels of acetic, propionic, butyric and hexanoic acid were reduced in mouse intestine, and the AKT-mTOR signaling pathway was activated in mouse BM cells after benzene exposure. Our results demonstrate that benzene induced immunosuppression in mice, and the B lymphocytes in BM are more sensible to benzene-induced toxicity. The reduction in mouse intestinal SCFAs as well as the activation of AKT-mTOR signaling may be related to the occurrence of benzene immunosuppression. Our study provides new insight for further mechanistic research on benzene-induced immunotoxicity.

A phase I study of the combination of palbociclib and dexamethasone for the treatment of relapsed or refractory B-cell acute lymphoblastic leukemia

PurposeDespite advances in the treatment of B-cell acute lymphoblastic leukemia (B-ALL), outcomes for relapsed/refractory (R/R) disease remain poor. Preclinical studies suggest that the combination of the CDK4/6 inhibitor palbociclib and dexamethasone may be effective in targeting leukemic cell growth. We conducted a phase I study of escalating doses of palbociclib in combination with dexamethasone in adults with R/R B-ALL. MethodsCycle 1 consisted of single agent palbociclib given for 7 days and continued for 28 additional days in combination with dexamethasone 20 mg daily. Palbociclib dosing began at 100 mg daily. Patients with a response were eligible for maintenance consisting of 1 week of palbociclib plus dexamethasone (20 mg daily × 2 days, 16 mg daily × 2 days, 12 mg daily × 2 days, 6 mg daily × 1 day), followed by 3 weeks of palbociclib alone. Safety, efficacy, and the expression of phospho-RB and c-MYB/BCL-2 were measured. ConclusionsSeven patients were treated on study before it was closed early due to slow accrual. No dose limiting toxicities were identified. One patient had a complete response with incomplete hematologic recovery, suggesting possible efficacy of the treatment. Reduction in CD34+ cells, p-RB, c-MYB, and BCL-2 expression also suggested on-target therapy effects.

Abstract 1856: Pemetrexed-cisplatin-bevacizumab combo in lung cancer models: impact on tumor immunity

Abstract Dual chemotherapy (i.e., Pemetrexed and Cisplatin, CT) plus anti-VEGF Bevacizumab could be associated with anti-PD1 such as Pembrolizumab in NSCLC patients with low PDL1 levels. To support this new combination, to what extent those drugs could reshape tumor immunity remains to be evaluated, prior to establishing optimal scheduling or sequencing with Pembrolizumab. Both Pemetrexed and Cisplatin are expected to trigger immunogenic cell death, whereas Bevacizumab could help T lymphocytes to extravasate and better infiltrate tumor micro-environment. Here, we studied the impact of Cisplatin and Pemetrexed at two dose levels (i.e., low dose and Maximal Tolerated Dose, MTD) and fixed flat-dose Bevacizumab, alone or in combination (i.e., Cisplatin, Pemetrexed, Cisplatin + Pemetrexed, with our without Beva), on the immune repertoire of BalbC mice ectopically grafted with KLN-205 murine lung tumors. CD45, CD4, CD8, FoxP3-CD4 (Tregs), and MDSCs were monitored by FACS analysis in blood, spleen, and tumors on D2, D7, D14, and D21 after treatment. Results were normalized by CD45 counts. All treatments led to an increase in CD4+ T cells in blood as compared with control (i.e., untreated) animals. Little increase was observed in tumors, regardless of the treatments but mice treated with the Beva+CT combo (both low dose and MTD CT) showed an increase in CD4+ in the spleen on D14. Regarding CD8+ T cells, all treatments led to an increase from D2 to D7. Beva + CT low dose led to a continuous increase in CD8+ cells, whereas in Beva+CT MTD mice, after an initial increase, a reduction in CD8+ was observed after D7 eventually. In the spleen, CD8+ proved to be stable apart from the Beva + CT low dose group which showed an increase up to D14. In tumors, an increase in CD8+ cells was observed in all the groups. No change in MDSCs levels was observed, regardless of the drugs, the dosing and the organ. Conversely, Tregs decreased in the blood in the Beva + CT low-dose group on D14, and decreased in spleen and tumors as compared with Control mice, regardless of the drugs and the dosing. Overall, our data suggest that the triple combination between Beva, Pemetrexed, and Cisplatin has a stronger impact on immune cells than each drug used as a single agent. MDSCs were the only cells to be unaffected by the treatments. Dosing could be relevant as well since the reduction in CD8+ T cells observed with MTD CT could come from drug-related lymphopenia. The Beva followed by low dose Pemetrexed + Cisplatin group is thus the more likely to harness tumor immunity, with peaks in CD4+ and CD8+ T cells and drop in Tregs observed on D14. This pilot study suggests therefore that sequencing Beva + CT low dose followed by a two-week lag time prior to administrating anti-PD1 could lead to synergism in lung cancer models. Citation Format: Guillaume Sicard, Sarah Giacometti, Fabrice Barlesi, Raphaelle Fanciullino, Joseph Ciccolini. Pemetrexed-cisplatin-bevacizumab combo in lung cancer models: impact on tumor immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1856.

Abstract 906: Development of a repeated challenge potency assay for evaluation of immune cell-mediated cytotoxicity in vitro

Abstract The development of immunotherapies relies on the use of in vitro potency assays - which are key for understanding complex interactions between immune (effector) cells and cancer (target) cells - to evaluate the function, specificity, and sensitivity of a product. A variety of in vitro assays are used to characterize the proliferation, cytokine release, and cell-mediated cytotoxicity of engineered immune cells, such as chimeric antigen receptor (CAR) T cells, each representing an important aspect driving clinical efficacy of the cellular product. Importantly, adoptive cell therapies must exhibit potent tumor killing over a prolonged period in vivo. Here, we describe an in vitro potency assay that quantifies immune cell-mediated cytotoxicity in response to repeated challenges with target cells. The repeated challenge assay was performed with two separate protocols, each providing a unique assessment of the effector cell function. In the first method, SKOV3 target cells (5k cells/well) were seeded into a multiwell microplate with embedded electrodes in the substrate. Electrical impedance measurements from the electrodes in each well detected the attachment and proliferation of the target cells. HER-2 specific CAR T effector cells were added 24 hours after the target cells and co-cultured with the target cells at a 1:1 effector to target ratio. Cytolysis of the target cells was calculated by comparing treated wells to no treatment control wells. Additional SKOV3 target cells (5k per well) were added every 24 hours for the repeated challenge conditions, with total tumor cell killing computed from the area under the impedance curve. The repeated challenge condition reached complete killing after the 6th tumor cell challenge (144 hours after first effector addition), whereas the single challenge condition reached complete killing within 96 hours of effector addition. Flow cytometry analysis revealed that the effector cells proliferated significantly more for the repeated challenge condition (4.7 fold increase) than the single challenge condition (1.5 fold increase). In the second method, the CAR T cells were removed after each challenge, counted, and added to a fresh plate of SKOV3 target cells at a 1:1 effector to target cell ratio. Here, the E:T ratio was kept constant for each challenge, allowing a direct comparison of the killing kinetics (KT50) for each subsequent challenge. The KT50 decreased from the first challenge (19.9 hr) to the fourth challenge (83.5 hr). Flow cytometry analysis revealed a reduction in CD8+ cells for the repeated challenge condition, indicating a change in the make-up of the immune cell population. The paradigms described above facilitate a label-free, in vitro workflow to assess potency of immune effector cells across repeated challenges, with the opportunity to incorporate additional assays, like flow cytometry or cytokine release, after each successive challenge. Citation Format: Denise Sullivan, Stacie Chvatal, Daniel Millard. Development of a repeated challenge potency assay for evaluation of immune cell-mediated cytotoxicity in vitro [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 906.

LBA01-08 EFFICACY OF TARGETED MAST CELL INHIBITION THERAPY IN CHRONIC PROSTATITIS/CHRONIC PELVIC PAIN SYNDROME

You have accessJournal of UrologyCME1 Apr 2023LBA01-08 EFFICACY OF TARGETED MAST CELL INHIBITION THERAPY IN CHRONIC PROSTATITIS/CHRONIC PELVIC PAIN SYNDROME Praveen Thumbikat, Goutham Pattabiraman, Catherine Osborn, Stephen Murphy, and Anthony Schaeffer Praveen ThumbikatPraveen Thumbikat More articles by this author , Goutham PattabiramanGoutham Pattabiraman More articles by this author , Catherine OsbornCatherine Osborn More articles by this author , Stephen MurphyStephen Murphy More articles by this author , and Anthony SchaefferAnthony Schaeffer More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003360.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a component of urologic chronic pelvic pain syndrome (UCPPS) and affects men, leading to chronic pain in the pelvic region or genitalia that is often accompanied by increased urinary frequency and urgency as well as sexual dysfunction. CPPS has an estimated prevalence rate of 6-12% of the male population with most diagnoses between the ages of 35-45. We have previously demonstrated that mast cells can be critical mediators of both chronic pelvic pain and lower urinary tract symptoms (LUTS). In this pilot clinical study, we therefore sought to identify subtypes of CP/CPPS characterized by mast cell dysfunction and evaluate the therapeutic efficacy of functional mast cell targeting on mast cell tryptase levels as well as on symptoms of pain and voiding dysfunction. METHODS: Men with CP/CPPS were recruited and evaluated in an open label, interventional uncontrolled trial after therapy with cromolyn sodium and cetirizine hydrochloride. The primary endpoint was a change in mast cell tryptase concentrations after treatment while secondary endpoints were changes in the NIH-CPSI and AUA-SI. Isolated cells from post-prostatic massage urine were evaluated for immune changes using mRNA expression analysis. RESULTS: 31 patients with a diagnoses of Category III CP/CPPS were consented, 25 patients qualified and 20 completed the study after meeting a prespecified threshold for active tryptase in expressed prostatic secretions. After treatment with cromolyn sodium and cetirizine dihydrochloride for 3-weeks, active tryptase concentrations were significantly reduced from 49.03±14.05 ug/ml to 25.49±5.48 ug/ml (p<0.05). The NIH-CPSI total score was reduced with a mean difference of 5.2±1 along with reduction in the pain, urinary and quality of life sub scores (p<0.001). A reduction in the AUA-SI was observed following treatment (p<0.05). NanoString mRNA analysis of isolated cells revealed downregulation of immune related pathways including Th1 and Th17 T cell differentiation and TLR signaling. Marked reduction in CD45+ cells and specifically macrophages and neutrophil abundance was observed. CONCLUSIONS: This pilot study presents a method to identify CP/CPPS patients with mast cell dysfunction and target them for therapeutic intervention using a novel, safe combination therapeutic approach. The resulting subgroup of CP/CPPS patients were shown to have a therapeutic response as measured primarily by a reduction in mast cell tryptase, a potential surrogate biomarker and reduction in CP/CPPS symptoms. These pilot studies will form the basis for future randomized placebo-controlled studies to evaluate these agents as CP/CPPS therapies. Source of Funding: This work was supported by the National Institute of Diabetes and Digestive and Kidney (NIDDK) grant R01DK083609 to Praveen Thumbikat. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of this abstract © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1179 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Praveen Thumbikat More articles by this author Goutham Pattabiraman More articles by this author Catherine Osborn More articles by this author Stephen Murphy More articles by this author Anthony Schaeffer More articles by this author Expand All Advertisement PDF downloadLoading ...

Impact of Covid 19 pandemic on hematopoietic stem cell transplantation activities: Report from a single center

The current COVID-19 pandemic has placed unprecedented stress on the healthcare system, including HSCT. Several international organizations have created guidelines for managing different aspects of HSCT in the context of the pandemic. Comparing 2019 and 2020, our transplant center performed the same number of transplants. In both periods, transplants were mainly for patients with acute leukemia; thus, the urgency criteria was respected in light of pandemic restraints. Transplants by sibling donors and cord blood units remained the same, while transplants by unrelated donors were increased, in particular from European registries, and transplants by haploidentical donors were decreased. This change was made in light of the necessity of cryopreserving all apheresis products. We decided against cryopreserving bone marrow products due to the greater risk of drastic reduction in CD34 + cell count during the process. For urgent cases with only a haploidentical donor available, we opted for the use of PBSC following stimulation with G-CSF. GvHD prophylaxis was performed with PTCY on days + 3 + 5, cyclosporine with tapering from day + 100, and mycophenolic acid until day + 90 post-HSCT. Post-transplant outcomes such as graft failure, sepsis, and GVHD were not affected by the changes implemented. As a result of logistic difficulties, we halted our Car-T program from the start of the lockdown in March 2020 until September 2020. In accord with international guidelines, we were able to continue our HSCT program in the order to ensure a lifesaving treatment for patients with hematologic diseases for whom this procedure cannot be postponed.

Salidroside alleviates cognitive impairment by inhibiting ferroptosis via activation of the Nrf2/GPX4 axis in SAMP8 mice

BackgroundAlzheimer's disease (AD) is a neurogenerative disease and remains no effective method for stopping its progress. Ferroptosis and adaptive immunity have been proven to contribute to AD pathogenesis. Salidroside exhibits neuroprotective and immunomodulatory effects. However, the underlying mechanisms linking salidroside, ferroptosis, and adaptive immunity in AD remain uncertain. PurposeThe objective of this study is to explore the neuroprotective effects and the potential molecular mechanisms of salidroside against neuronal ferroptosis and CD8+ T cell infiltration in senescence-accelerated mouse prone 8 (SAMP8) mice. Study design and methodsSAMP8 mice were employed as an AD model and were treated with salidroside for 12 weeks. Behavioral tests, immunohistochemistry, HE and Nissl staining, immunofluorescence, transmission electron microscopy, quantitative proteomics, bioinformatic analysis, flow cytometry, iron staining, western blotting, and molecular docking were performed. ResultsTreatment with salidroside dose-dependently attenuated cognitive impairment, reduced the accumulation of Aβ plaques and restored neuronal damage. Salidroside also suppressed the infiltration of CD8+T cells, oxidative stress, and inflammatory cytokines, and improved mitochondrial metabolism, iron metabolism, lipid metabolism, and redox in the SAMP8 mice brain. The administration of salidroside decreased iron deposition, reduced TFR1, and ACSL4 protein expression, upregulated SLC7A11, and GPX4 protein expression, and promoted the Nrf2/GPX4 axis activation. ConclusionIn conclusion, neuronal ferroptosis and CD8+T cells are involved in the process of cognitive impairment in SAMP8 mice. Salidroside alleviates cognitive impairment and inhibits neuronal ferroptosis. The underlying mechanisms may involve the Nrf2/GPX4 axis activation and reduction in CD8+T cells infiltration. This study provides some evidence for the roles of salidroside in adaptive immunity and neuronal ferroptosis in SAMP8 mice.

T cell maturation is significantly affected by SARS-CoV-2 infection.

Coronavirus disease 2019 (COVID-19) is a respiratory tract infection caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). An adequate T cell response is essential not only for fighting disease but also for the creation of immune memory. Thus, the present study aims to evaluate the T cells of patients with moderate, severe and critical COVID-19 not only at the time of illness but also 2 months after diagnosis to observe whether changes in this compartment persist. In this study, 166 COVID-19 patients were stratified into moderate/severe and critical disease categories. The maturation and activation of T cells were evaluated through flow cytometry. In addition, Treg cells were analysed. Until 15 days after diagnosis, patients presented a reduction in absolute and relative T lymphocyte counts. After 2 months, in moderate/severe patients, the counts returned to a similar level as that of the control group. In convalescent patients who had a critical illness, absolute T lymphocyte values increased considerably. Patients with active disease did not show differentiation of T cells. Nonetheless, after 2 months, patients with critical COVID-19 showed a significant increase in CD4+ EMRA (CD45RA+ effector memory) T lymphocytes. Furthermore, COVID-19 patients showed delayed T cell activation and reduced CD8+ suppressor T cells even 2 months after diagnosis. A reduction in CD4+ Treg cells was also observed, and their numbers returned to a similar level as that of healthy controls in convalescent patients. The results demonstrate that COVID-19 patients have a delayed activation and differentiation of T cells. In addition, these patients have a great reduction of T cells with a suppressor phenotype.