Peripheral Blood T-cell Research Articles

Efficacy of PD-1 inhibitors in the treatment of advanced gastrointestinal tumors and the effect on T-lymphocyte subsets and IL-6 levels in patients.

44 Background: Immune checkpoint inhibitors (ICIs) have improved the therapeutic prospects in advanced gastrointestinal tumors. The PD-L1 expression has become one of predictive biomarkers for immunotherapy and used in treatment, but there are still some drawbacks. The aim of this study was to investigate the changes in peripheral blood T-lymphocyte subsets, IL-6 levels before and after treatment with ICIs and clinical significance. Methods: 70 patients with advanced gastrointestinal tumors who were hospitalized in Shaanxi Provincial People's Hospital from January 2020 to December 2022 were selected. 30 healthy patients were selected as controls. PD-L1 was detected by immunohistochemistry. Patients were treated with ICIs (sintilimab or pembrolizumab). 1 day before treatment, 20 days after the end of the 4 cycles of treatment, peripheral venous blood was collected and CT or MRI was performed to evaluate the therapeutic effect. Complete response (CR), partial response (PR), and stable disease (SD) were classified as immune response group, and progressive disease (PD) was classified as immune non-response group. To evaluate the effects of ICIs on the levels of T-lymphocyte subsets (Percentage of CD3+T cells, percentage of CD4+T cells, percentage of CD8+T cells, CD4+/CD8+, CD3+T cells, CD4+T cells, CD8+T cells) and IL-6. Results: Compared to controls, CD3+T cells, CD4+T cells, CD8+T cells and CD4+/CD8+ were significantly lower ( P<0.05). After 4 cycles of immunotherapy, the CD3+T cells, CD4+T cells, CD8+T cells, and CD4+/CD8+ levels were significantly higher ( P<0.05), and IL-6 levels were lower ( P<0.05). After 4 cycles of treatment, 48 cases were divided in the immune response group and 22 cases in the immune non-response group, with a treatment efficiency of 68.6%. In the immune response group compared to the immune non-response group, the levels of percentage of CD4+T cells, CD4+/CD8+, CD3+T cells and CD4+T cells were significantly higher ( P<0.05), while the percentage of CD8+T cells level was lower ( P<0.05). The percentage of CD4+T cells, CD4+/CD8+, CD3+T cells, CD4+T cells and CD8+T cells were significantly higher ( P<0.05) in the immune response group after 4 cycles of immunotherapy, while the percentage of CD8+T cells level was lower ( P<0.05) compared to before immunotherapy. The percentage of CD4+T cells and CD4+/CD8+ were significantly lower ( P<0.05), the percentage of CD8+T cells and CD8+T cells were higher ( P<0.05) in the immune non-response group compared to before immunotherapy. In the immune response group, the percentage of CD4+T cells was higher in the PD-L1 high expression groups (≥ 50%) compared to the PD-L1 low expression groups (< 50%) ( P<0.05). Conclusions: PD-1 inhibitors can affect the distribution of immune cells such as T-lymphocyte subsets in patients with advanced gastrointestinal tumors and improve the immune status of patients.

Immunopeptidome profiling of human coronavirus OC43-infected cells identifies CD4 T-cell epitopes specific to seasonal coronaviruses or cross-reactive with SARS-CoV-2.

Seasonal "common-cold" human coronaviruses are widely spread throughout the world and are mainly associated with mild upper respiratory tract infections. The emergence of highly pathogenic coronaviruses MERS-CoV, SARS-CoV, and most recently SARS-CoV-2 has prompted increased attention to coronavirus biology and immunopathology, but the T-cell response to seasonal coronaviruses remains largely uncharacterized. Here we report the repertoire of viral peptides that are naturally processed and presented upon infection of a model cell line with seasonal coronavirus OC43. We identified MHC-bound peptides derived from each of the viral structural proteins (spike, nucleoprotein, hemagglutinin-esterase, membrane, and envelope) as well as non-structural proteins nsp3, nsp5, nsp6, and nsp12. Eighty MHC-II bound peptides corresponding to 14 distinct OC43-derived epitopes were identified, including many at very high abundance within the overall MHC-II peptidome. Fewer and less abundant MHC-I bound OC43-derived peptides were observed, possibly due to MHC-I downregulation induced by OC43 infection. The MHC-II peptides elicited low-abundance recall T-cell responses in most donors tested. In vitro assays confirmed that the peptides were recognized by CD4+ T cells and identified the presenting HLA alleles. T-cell responses cross-reactive between OC43, SARS-CoV-2, and the other seasonal coronaviruses were confirmed in samples of peripheral blood and peptide-expanded T-cell lines. Among the validated epitopes, spike protein S903-917 presented by DPA1*01:03/DPB1*04:01 and S1085-1099 presented by DRB1*15:01 shared substantial homology to other human coronaviruses, including SARS-CoV-2, and were targeted by cross-reactive CD4 T cells. Nucleoprotein N54-68 and hemagglutinin-esterase HE128-142 presented by DRB1*15:01 and HE259-273 presented by DPA1*01:03/DPB1*04:01 are immunodominant epitopes with low coronavirus homology that are not cross-reactive with SARS-CoV-2. Overall, the set of naturally processed and presented OC43 epitopes comprise both OC43-specific and human coronavirus cross-reactive epitopes, which can be used to follow CD4 T-cell cross-reactivity after infection or vaccination, and to guide selection of epitopes for inclusion in pan-coronavirus vaccines.

Synergistic efficacy of PI3Kδ inhibitor with anti-PD-1 mAbs in immune-humanized PDX model of endocrine resistance hormone receptor-positive advanced breast cancer

PurposeEndocrine resistance hormone receptor-positive (HR+) advanced breast cancer (ABC) is generally insensitive to immunecheckpoint inhibitors (ICIs). This study sought to determine whether PI3Kδ inhibitor could enhance the sensitivity of endocrine resistance HR + advanced BC to ICIs by reducing immune evasion. MethodsPatient-derived HR + ABC xenografts were implanted into immune-humanized NSG mice and subsequently treated with YY20394 (PI3Kδ inhibitor) and camrelizumab. The mice were monitored for tumor progression, biochemical blood indicators, and peripheral blood T-cell subsets. The xenografted tumors were collected at the end of the treatment cycle and subjected to HE staining, immunohistochemistry and protein phosphorylation analysis. Besides, the xenografted tumors were also used to isolate primary breast cancer cells (BCCs) and regulatory T-cells (Tregs), which were subsequently used to evaluate drug sensitivity in vitro. ResultsThe humanized PDX model showed a favorable initial treatment response to camrelizumab combined with YY20394 and manageable toxicity. YY20394 plus camrelizumab showed a strong inhibitory effect on HR + BC in vivo mediated by suppression of Treg activity and an increased proportion of CD8+ T cells. Mice bearing tumors treated with YY20394 and camrelizumab had less invasion, mitotic figures, and ki67 expression, while having higher IL-12 expression compared with other groups. Mechanistically, YY20394 only effectively inhibited the PI3K pathway and proliferation activity in Tregs but not in BCCs. ConclusionOur study suggests PI3Kδ inhibitor could the enhance the efficacy of ICIs in HR + BC PDX models by combating immune suppression and provides a feasible approach that may overcome the resistance of ICIs in HR + BC patients.

Anticancer effects of herbal medicine Emelia-M, Mshikazi and Delosma H against human leukaemia cells.

Leukaemia is one of the three major types of blood cancers that lead to the overproduction of abnormal white blood cells. Emelia M (EMB), Mshikazi and Delosma H are herbal medicines that are being used by traditional healers in KwaZulu-Natal, South Africa to treat leukaemia and other diseases. To gain insight into the safety (non-toxic effect), anti-cancer activity, mechanisms of action and phytochemical profiles of traditional herbal medicines (Emelia M (EMB), Mshikazi and Delosma H) in South Africa. The viability of human peripheral blood mononuclear cells (PBMCs), monocytic (THP-1) and T-lymphocyte (Jurkat) cell lines exposed to varying concentrations of aqueous extracts of the three herbal medicines were assessed using adenosine triphosphate (ATP) assay. All three extracts showed a dose-dependent effect on the viability of PBMCs. Cell viability decreased with increasing concentrations of extracts when compared with the untreated cells at 24 and 48 hours. The inhibitory activities (IC50) of the extract were found in the order of Mshikazi > EMB, > Delosma H. All the extracts induced apoptosis with minimal necrosis. Many bioactive compounds that have been previously reported to have anticancer effects were identified in the extracts. Mshikazi extract significantly inhibited the growth of THP-1 and Jurkat cells and induced cell death through apoptosis than the other two extracts.

The specifics of CpG islets methylation of some genes of peripheral blood T-lymphocytes in breast cancer patients before and after treatment

Introduction. The growth of primary breast tumor morbidity in the last ten years and increased number of patients with disseminated breast cancer in the Republic of Kazakhstan require the search for methods of early diagnosis of malignant tumors. Determination of breast cancer markers in epigenetic studies allows to use them as diagnostic signs of the presence of malignant tumor and as predictors of treatment effectiveness in patients with this pathology.Aim. To perform a search for therapeutic and prognostic breast cancer markers.Materials and methods. The study included samples of biological material (peripheral blood) of 50 deemed healthy individuals and 103 patients with locally advanced and disseminated breast cancer receiving special therapy. The following methods were used: blood collection, DNA extraction, creation of DNA methylation profiles, sequencing, statistical data analysis.Results. The results of search for epigenetic mutations in peripheral blood of patients with breast cancer showed their role as specific diagnostic, therapeutic and prognostic markers with specificity 0.91 % and sensitivity 0.94 %. The hypothesis on therapeutic significance of identified earlier diagnostic markers in patients with breast cancer, namely hypermethylation of CpG islands associated with genes JAM3, C17orf64, MSC, C7orf51 and CpG island associated with intragene part of chromosome 5 (chr5: 77,208,034–77,329,434) was tested and confirmed.Conclusion. A correlation between DNA methylation characteristics and disease progression during treatment was shown. The study results can be used in clinical practice: epigenetic markers, such as methylation in the CpG islets associated with the JAM3, C17orf64, MSC, C7orf51 genes, and in the CpG islet associated with the intragenic site of chromosome 5 (chr5: 77,208,034–77,329,434) can be used as prognostic markers and therapeutic predictors of breast cancer.

The Impact of Biologic Treatment on PD-1/PD-L1 Pathway Disturbances in Psoriasis.

The programmed death-1 (PD-1) receptor plays a major physiological role in the maintenance of immune tolerance and, by interaction with its ligands (PD-L1 and PD-L2), prevents the development of multiple immune-mediated diseases. There is growing evidence of the PD-1/PD-L1 pathway playing an important role in the pathogenesis of psoriasis. In total, 84 subjects with psoriasis were included in this study, together with 29 healthy subjects as a control group. Twenty-eight of the psoriatic patients were treated with biologic therapy (TNF-alpha, interleukin (IL)-12/23, or IL-17 inhibitors). The amounts of PD-1- and PD-L1-positive T-cells in peripheral blood were evaluated using flow cytometry. Significantly lower levels of peripheral blood mononuclear cells (PBMCs) with the expression of PD-1 and PD-L1 were found in psoriatic patients compared to healthy individuals, i.e., CD3/PD-1-, CD3/PD-L1-, CD4/PD-1-, CD4/PD-L1-, CD8/PD-L1-, CD19/PD-1-, and CD19/PD-L1-positive cells. Biologic treatment resulted in the elevation of CD3/PD-L1- and CD8/PD-L1- and a decrease in CD8/PD-1-positive PBMCs. Our results confirm previous observations of the PD-1/PD-L1 pathway being disrupted in psoriasis, and that these disturbances may play an important role in development of the disease. Biologic drugs may reverse several abnormalities observed within this pathway, which may explain their excellent efficacy in the treatment of psoriasis. Further research should be conducted to fully explain the results obtained.

Rapid reduction in Staphylococcus aureus in atopic dermatitis subjects following dupilumab treatment

Atopic dermatitis (AD) is an inflammatory disorder characterized by dominant type 2 inflammation leading to chronic pruritic skin lesions, allergic comorbidities, and Staphylococcus aureus skin colonization and infections. S aureus is thought to play a role in AD severity. This study characterized the changes in the host-microbial interface in subjects with AD following type 2 blockade with dupilumab. Participants (n= 71) with moderate-severe AD were enrolled in a randomized (dupilumab vs placebo; 2:1), double-blind study at Atopic Dermatitis Research Network centers. Bioassays were performed at multiple time points: S aureus and virulence factor quantification, 16s ribosomal RNA microbiome, serum biomarkers, skin transcriptomic analyses, and peripheral blood T-cell phenotyping. At baseline, 100% of participants were S aureus colonized on the skin surface. Dupilumab treatment resulted in significant reductions in S aureus after only 3 days (compared to placebo), which was 11 days before clinical improvement. Participants with the greatest S aureus reductions had the best clinical outcomes, and these reductions correlated with reductions in serum CCL17 and disease severity. Reductions (10-fold) in S aureus cytotoxins (day 7), perturbations in TH17-cell subsets (day 14), and increased expression of genes relevant for IL-17, neutrophil, and complement pathways (day 7) were also observed. Blockade of IL-4 and IL-13 signaling, very rapidly (day 3) reduces S aureus abundance in subjects with AD, and this reduction correlates with reductions in the type 2 biomarker, CCL17, and measures of AD severity (excluding itch). Immunoprofiling and/or transcriptomics suggest a role for TH17 cells, neutrophils, and complement activation as potential mechanisms to explain these findings.

Effector memory CD8 T-cells as a novel peripheral blood biomarker for activated T-cell pediatric acute liver failure.

A distinct phenotype of pediatric acute liver failure (PALF) has been identified, labeled activated T-cell hepatitis. These patients, previously included within the indeterminate group, have evidence of systemic immune activation and liver biopsy specimens with dense infiltration of CD8+ T-cells. We aimed to evaluate the peripheral blood T-cell phenotype in PALF patients with activated T-cell hepatitis compared to indeterminate cause. PALF patients with unknown etiology age 1-17 years were prospectively enrolled between 2017-2020. Within the unknown group, patients were classified as either activated T-cell hepatitis if they had a liver biopsy with dense or moderate CD8 staining and an elevated soluble interleukin-2 receptor level, or they were classified as indeterminate if they did not meet these criteria. Whole blood was collected for flow cytometry and T-cell phenotyping. Four patients with activated T-cell hepatitis and 4 patients with indeterminate PALF were enrolled. Activated T-cell hepatitis patients had significantly greater percentage of CD8 T-cells that were effector memory (TEM) phenotype compared to indeterminate PALF patients (median 66.8% (IQR 57.4-68.7) vs 19.1% (IQR 13.4-25.2), P = 0.03). In addition, CD8+ TEM cells in activated T-cell hepatitis patients were significantly more likely to be CD103 positive, a marker of tissue resident memory T-cells, compared to indeterminate PALF patients (median 12.4% (IQR 9.5-14.7) vs 4.7% (IQR 4.5-5.3), P = 0.03). We found patients with activated T-cell hepatitis can be identified by the unique pattern of increased percentage of peripheral blood effector memory CD8+ CD103+ T-cells. These findings will guide future studies exploring the T-cell phenotype for these patients and whether they may respond to directed immunosuppressive therapies.

Tissue-resident memory CAR T cells with stem-like characteristics display enhanced efficacy against solid and liquid tumors

Chimeric antigen receptor (CAR) Tcells demonstrate remarkable success in treating hematological malignancies, but their effectiveness in non-hematopoietic cancers remains limited. This study proposes enhancing CAR Tcell function and localization in solid tumors by modifying the epigenome governing tissue-residency adaptation and early memory differentiation. We identify that a key factor in human tissue-resident memory CAR Tcell (CAR-TRM) formation is activation in the presence of the pleotropic cytokine, transforming growth factor β (TGF-β), which enforces a core program of both "stemness" and sustained tissue residency by mediating chromatin remodeling and concurrent transcriptional changes. This approach leads to a practical and clinically actionable invitro production method for engineering peripheral blood Tcells into a large number of "stem-like" CAR-TRM cells resistant to tumor-associated dysfunction, possessing an enhanced ability to accumulate in situ and rapidly eliminate cancer cells for more effective immunotherapy.

Peripheral T cell profiling reveals downregulated exhaustion marker and increased diversity in lymphedema post-lymphatic venous anastomosis

Lymphedema is a progressive condition accompanying cellulitis and angiosarcoma, suggesting its association with immune dysfunction. Lymphatic venous anastomosis (LVA) can provide relief from cellulitis and angiosarcoma. However, the immune status of peripheral Tcells during lymphedema and post-LVA remains poorly understood. Using peripheral blood Tcells from lymphedema, post-LVA, and healthy controls (HCs), we compared the profile of Tcell subsets and Tcell receptor (TCR) diversity. PD-1+ Tim-3 + expression was downregulated in post-LVA compared with lymphedema. IFN-γ levels in CD4+PD-1+ Tcells and IL-17A levels in CD4+ Tcells were downregulated in post-LVA compared with lymphedema. TCR diversity was decreased in lymphedema compared with HCs; such TCR skewing was drastically improved in post-LVA. Tcells in lymphedema were associated with exhaustion, inflammation, and diminished diversity, which were relieved post-LVA. The results provide insights into the peripheral Tcell population in lymphedema and highlight the immune modulatory importance of LVA.

Preliminary analysis of double-negative T, double-positive T, and natural killer T-like cells in B-cell chronic lymphocytic leukemia.

B-cell chronic lymphocytic leukemia (B-CLL) is characterized by the expansion of CD5+ malignant B lymphocytes. Recent discoveries have shown that double-negative T (DNT) cells, double-positive T (DPT) cells, and natural killer T (NKT)-cells may be involved in tumor surveillance. A detailed immunophenotypic analysis of the peripheral blood T-cell compartment of 50 patients with B-CLL (classified in three prognostic groups) and 38 healthy donors (as controls) matched for age was performed. The samples were analyzed by flow cytometry using a stain-lyse-no wash technique and a comprehensive six-color antibody panels. Our data confirmed a reduction in percentage values and an increase in absolute values of T lymphocytes in patients with B-CLL, as already reported. In particular, DNT, DPT, and NKT-like percentages were significantly lower than in the controls, except for NKT-like in the low-risk prognostic group. Moreover, a significant rise in the absolute counts of DNT cells in each prognostic group and in the low-risk prognostic group of NKT-like cells was found. A significant correlation of the absolute values of NKT-like cells in the intermediate-risk prognostic group versus B cells was observed. Furthermore, we analyzed whether the increase in T cells was related to the subpopulations of interest. Only DNT cells were positively correlated with the increase in CD3+ T lymphocytes, regardless of the stage of the disease, supporting the hypothesis that this T-cell subset plays a key role in the immune T response in B-CLL. These early results supported that DNT, DPT, and NKT-like subsets may be related to disease progression and should encourage further studies aimed at identifying the potential immune surveillance role of these minority T subpopulations.

Peripheral blood T-lymphocyte subsets are potential biomarkers of disease severity and clinical outcomes in patients with ulcerative colitis: a retrospective study

BackgroundUlcerative colitis (UC) is considered an immune-mediated disease. The disorder of T-lymphocyte subsets plays an important role in the pathogenesis of UC. The aim of this study was to evaluate the significance of peripheral blood T-lymphocyte subsets in assessing disease severity and predicting clinical outcomes in UC patients.MethodsThe retrospective case-control study was performed in 116 UC patients with active disease and 90 healthy controls (HC). The UC patients included were followed up for 180 days. Analyses of t-test, Spearman’s correlation coefficient, multivariable Cox regression analysis, receiver operating characteristic (ROC) curves and cumulative survival analysis were done.ResultsThe UC patients had lower proportions of CD4+T cells (42.85%±9.77% vs 45.71%±7.94%, P=0.021) and higher proportion of CD8+T cells (27.88%±8.86% vs 25.00%±6.47%, P=0.008) than HC. The severely active UC patients had higher proportion of CD3+HLA-DR+ T cells (8.83%±6.55% vs 2.80%±1.55%, P<0.001; 8.83%±6.55% vs 4.06%±5.01%, P<0.001) and CD8+T cells (31.35%±8.49% vs 26.98%±7.98%, P=0.029; 31.35%±8.49% vs 25.46%±9.15%, P=0.003) than mild and moderate group, whereas lower proportion of CD4+CD25+T cells (2.86%±1.35% vs 3.46%±1.07%, P=0.034) than mild group and CD4+T cells (40.40%±9.36% vs 44.73%±10.39%, P=0.049) than moderate group. The area under the curve (AUC) of CD3+HLA-DR+ T cells for assessing severely active UC was 0.885, with the cut-off value of 5.33%. The sensitivity was 76.32% and specificity was 89.74%. The combination of CD3+HLA-DR+ T cells and CRP had stronger assessment value with AUC of 0.929. The AUC of CD8+T cells, CD4+/CD8+ ratio and CD4+CD25+T cells for assessing disease severity was 0.677, 0.669 and 0.631 respectively. Within the 180 days follow-up, 24 patients (20.69%) had UC-related readmission or surgery, with higher proportion of CD3+HLA-DR+ T cells (10.66%±9.52% vs 3.88%±2.56%, P=0.003) and CD8+T cells (31.19%±10.59% vs 27.01%±8.20%, P=0.039) than those without readmission and surgery. The proportion of CD3+HLA-DR+ T cells was the independent predictor of UC-related readmission or surgery (HR=1.109, P=0.002). The AUC of CD3+HLA-DR+ T cells for predicting readmission or surgery was 0.796 with the cut-off value of 5.38%. UC patients with CD3+HLA-DR+T cells proportion>5.38% had a shorter time to readmission or surgery (log-rank test, P<0.001).ConclusionsThe combination of CD3+HLA-DR+T cells and CRP may be potential biomarker of disease severity in UC patients. The high proportion of CD3+HLA-DR+T cells may be associated with an increased risk of readmission or surgery in UC patients.

Evaluation of peripheral blood T-lymphocyte subpopulations features in patients with hepatitis B virus-related acute-on-chronic liver failure based on single-cell sequencing technology

Objective: T lymphocyte exhaustion is an important component of immune dysfunction. Therefore, exploring peripheral blood-exhausted T lymphocyte features in patients with hepatitis B virus-related acute-on-chronic liver failure may provide potential therapeutic target molecules for ACLF immune dysfunction. Methods: Six cases with HBV-ACLF and three healthy controls were selected for T-cell heterogeneity detection using the single-cell RNA sequencing method. In addition, exhausted T lymphocyte subpopulations were screened to analyze their gene expression features, and their developmental trajectories quasi-timing. An independent sample t-test was used to compare the samples between the two groups. Results: Peripheral blood T lymphocytes in HBV-ACLF patients had different differentiation trajectories with different features distinct into eight subpopulations. Among them, the CD4(+)TIGIT(+) subsets (P = 0.007) and CD8(+)LAG3(+) (P = 0.010) subsets with highly exhausted genes were significantly higher than those in healthy controls. Quasi-time analysis showed that CD4(+)TIGIT(+) and CD8(+)LAG3(+) subsets appeared in the late stage of T lymphocyte differentiation, suggesting the transition of T lymphocyte from naïve-effector-exhausted during ACLF pathogenesis. Conclusion: There is heterogeneity in peripheral blood T lymphocyte differentiation in patients with HBV-ACLF, and the number of exhausted T cells featured by CD4(+)TIGIT(+)T cell and CD8(+)LAG3(+) T cell subsets increases significantly, suggesting that T lymphocyte immune exhaustion is involved in the immune dysfunction of HBV-ACLF, thereby identifying potential effective target molecules for improving ACLF patients' immune function.

Single-cell profiling of peripheral blood and muscle cells reveals inflammatory features of juvenile dermatomyositis.

Introduction: Juvenile dermatomyositis (JDM) is a rare yet serious childhood systemic autoimmune condition that primarily causes skin rashes and inflammatory myopathy of the proximal muscles. Although the associated immune response involves the innate and adaptive arms, a detailed analysis of the pertinent immune cells remains to be performed. This study aims to investigate the dynamic changes of cell type, cell composition and transcriptional profiles in peripheral blood and muscle tissues, and in order to clarify the involvement of immune cells in the pathogenesis of JDM and provide a theoretical reference for JDM. Methods: Single-cell RNA sequencing combined with bioinformatic analyses were used to investigate the dynamic changes in cell composition and transcriptional profiles. Results: Analysis of 45,859 cells revealed nine and seven distinct cell subsets in the peripheral blood and muscle tissues respectively. IFITM2+ and CYP4F3+ monocytes were largely produced, and CD74+ smooth muscle cells (SMCs) and CCL19+ fibroblasts were identified as inflammatory-related cell subtypes in JDM patients, exhibiting patient-specific cell population heterogeneity.The dynamic gene expression patterns presented an enhanced type I interferon response in peripheral blood monocytes and T-cells, and SMCs and fibroblasts in muscle of untreated JDM patients. EGR1 and IRF7 may play central roles in the inflammation in both CD74+ SMCs and CCL19+ fibroblasts. Moreover, inflammatory-related monocytes could regulate T-cells, and the interaction between immune cells and SMCs or fibroblasts in muscle was enhanced under the inflammatory state. Conclusions: Immune dysregulation is one of the key pathogenic factors of JDM, and type I interferon responses are significantly enhanced in peripheral blood Monos and T cells as well as SMCs and fibroblasts. EGR1 and IRF7 may play central roles in the inflammation and are considered as potential therapeutic targets for JDM.

457 CD39 Expression in the Glioblastoma Microenvironment does not Affect T Cell Exhaustion or Survival

INTRODUCTION: Glioblastoma (GBM), the most common malignant brain tumor, is notable for its dysfunctional T-cells. The initial optimism of Immune checkpoint inhibitors has been tempered as these agents have not been successful in treating GBM. CD39 is the first enzyme in the breakdown of ATP to adenosine and is highly upregulated in GBM. CD39 is also thought to contribute to T-cell exhaustion. However, inhibiting the CD39 ATP breakdown pathway did not improve survival in mice, even with PD-1 inhibition, leading to uncertainty about whether non-enzymatic functions of CD39 give it a role in T-cell exhaustion in GBM. METHODS: We performed intracranial injections of SB28 and GL261 GBM cell lines into CD39 global nulls (KO) and C57BL/6J (WT) mice and measured survival. Another cohort of mice were similarly injected and sacrificed after 2 weeks. These tumors were analyzed for T-cell exhaustion markers using flow cytometry. RESULTS: There was no survival benefit seen in either cell line when compared to wild type mice. The immune cell profile was not found to be statistically different between KO and WT mice. Next, expression of known exhaustion markers such as PD-1, TIM3, and LAG3 on tumor infiltrating lymphocytes (TILs) were analyzed. Expression of TIM3 and 2B4 were found to be increased in CD39KO TILs compared to WT (p &lt; 0.01). Additionally, numerous exhaustion markers such as LAG3, TIGIT, and CTLA4 were decreased on TILs compared to peripheral blood T-cells in tumor-bearing mice (p &lt; 0.01). CONCLUSIONS: These results suggest that CD39 lacks a direct impact on GBM outcomes but may affect the expression of other exhaustion markers. Further studies will continue to investigate the interaction between immune checkpoint molecules in GBM.

Features of Neurotrophic Control and Correlation with Eosinophils and CD2- Receptors of Peripheral Blood T-Lymphocytes in Patients with PostTraumatic Gunshot and Non-Gunshot Injuries of Nerves and Plexuses of Limbs

Introduction: Peripheral nerve injuries are common conditions with a broad spectrum of symptoms depending on the severity and nerves involved. Although a large amount of knowledge about the mechanisms of damage and regeneration has been accumulated, but the number of reliable methods of treatment that ensure full functional recovery is not enough. Materials and Methods: The study included 93 men aged 21 to 59 years with neuropathies and plexopathies, which were divided into 3 groups. All patients underwent neurological, electroneuromyographic, and ultrasound examination. Immunological research was carried out during 12 to 24 months after the onset of the disease. Results: In our study, we found a statistically significant correlation between the content of Beta-NGF and the level of peripheral blood eosinophils (R=0.41, p=0.0191) in patients with post-traumatic gunshot neuropathies and plexopathies. A correlation between the content of Beta-NGF and the CD2+ indicator levels (R=0.56, p=0.00105) in patients with post-traumatic non-gunshot neuropathies and plexopathies was revealed. Conclusion: The analysis of the received research data and literature resources demonstrates an important correlation between the neurotrophins and immunological indicators, which opens up further promising opportunities in the development and use of complex pathogenetic therapy of post-traumatic neuropathies and plexopathies in order to improve the restoration of impaired functions and the quality of life of patients.

Correlation analysis of the peripheral blood lymphocyte count and occurrence of pneumonia after lung transplantation

BackgroundInfections are the most common complication in patients after lung transplantation and the main cause of death at all stages after transplantation; therefore, awareness regarding the occurrence of infectious pneumonia after lung transplantation is vital. This study aimed to explore the correlation between the absolute lymphocyte and T-lymphocyte subpopulation counts in the peripheral blood and the occurrence of pneumonia after lung transplantation and to predict the risk of pneumonia development after lung transplantation. MaterialsPatients who underwent lung transplantation with long-term follow-up between June 2018 and December 2021 were prospectively included. The patients were divided into pneumonia and non-pneumonia groups. Demographic and clinical characteristics, and the levels of leukocytes, neutrophils, platelets, C-reactive protein (CRP), procalcitonin (PCT), serum albumin, peripheral blood T lymphocytes, and CD4+ and CD8+ T cells in the peripheral blood were measured in both groups. ResultsWe included 22 patients with post-lung transplants in the analysis. Of the 104 collected samples, 26 (56.5%) were pathogenically positive, 16 (61.5%) had bacterial infections, 7 samples (26.9%) had fungal infections, and 8 (30.8%) had viral infections. Patients with pneumonia had higher levels of peripheral blood neutrophils (P = 0.01), platelets (P = 0.03), and CRP (P < 0.001) than did those without pneumonia. Logistic regression analysis showed that the levels of peripheral blood neutrophils, total T lymphocytes, CRP, and PCT were associated with the development of pneumonia after transplantation (P < 0.05), as documented by their area under the curve (AUC) values of 0.702, 0.792, 0.899, and 0.789, respectively. The AUC for the combined receiver operating characteristic curve for predicting the development of pneumonia was 0.943, with a sensitivity of 91.3% and specificity of 93.1%. There was no significant difference in T-lymphocyte counts in patients with lung transplants between the pneumonia and non-pneumonia groups who were treated with two anti-rejection agents. In contrast, the absolute lymphocyte, total T-lymphocyte, and CD4+ and CD8+ T-cell counts in patients who developed pneumonia after treatment with three anti-rejection agents were lower than those in patients who did not develop pneumonia (P < 0.05). ConclusionBacterial pneumonia is more common after lung transplantation than after fungal or viral infections. Peripheral blood T-lymphocyte counts combined with neutrophil, CRP, and PCT levels had good predictive value for the development of pneumonia after lung transplantation. Monitoring of patients should be strengthened by implementing peripheral blood T-lymphocyte counts to improve the early identification and prevention of pneumonia after lung transplantation.

Dependence of the Translocation Frequency in Blood Lymphocytes on the Dose and Age at the Onset of Exposure in Residents of the Techa Riverside Settlements

Evaluation of age effect on the frequency of radiation-induced translocations, registered using FISH in circulating T-lymphocytes in the long-term period after exposure, is both of theoretical and practical interest for the purposes of biodosimetry. The objective of our study was to analyze the dose dependence of the translocation frequency in the peripheral blood T-lymphocytes in donors of different age who were exposed in the Techa Riverside settlements (n = 197). In cytogenetic studies, whole chromosome painting probes were used to stain three pairs of chromosomes. A total of 104,721 genome equivalents (GE) were calculated and 2,540 translocations were found. For each donor, the individual absorbed doses in organs and tissues at the time of blood sampling were calculated using the Techa River Dosimetry System. In addition, doses to T-lymphocytes and their progenitors were calculated using the innovative modelling approach with due account of age related-dynamics of T-lymphocytes. The age dependence of the translocation frequency was associated particularly with these doses. The main sources of donor exposure were 89,90Sr, accumulating in bones and irradiating the bone marrow almost locally. To assess the parameters of the dose-effect relationship, linear regression model was used. After taking into account background values, the lowest frequency of translocations per 1000 GE per Gy was found in donors aged 0–5 years at the time of exposure (9.3 ± 1.3), which is statistically significantly lower than in children aged 6–18 years (15.3 ± 1.5), but not in adults (11.9 ± 2.9). The value for adults (18 years) was characterized by the maximum scatter, but was close to the values obtained in an international study of nuclear enterprise personnel after external exposure (11.6 ± 1.6). The values of the background translocation frequencies registered in various age groups correspond to the published data obtained in a joint international study on unexposed donors. We have also confirmed the absence of sex-effect on the frequency of translocations.

LOW DOSE OF ESMOLOL ATTENUATES SEPSIS-INDUCED IMMUNOSUPPRESSION VIA MODULATING T-LYMPHOCYTE APOPTOSIS AND DIFFERENTIATION.

Background: Immunosuppression caused by immune cell apoptosis and an imbalance of T helper 2 cells (T H 2) and T helper 1 cells (T H 1), is associated with poor outcomes in septic patients. Esmolol was reported to improve survival by modulating immune responses in septic shock. Whether esmolol could alleviate sepsis-induced immunosuppression and the optimal dose are unclear. Methods: Four hours after cecal ligation and puncture (CLP), Wistar rats were randomized into CLP, CLP + E-5 (esmolol: 5 mg·kg -1 ·h -1 ) and CLP + E-18 (esmolol: 18 mg·kg -1 ·h -1 ) groups. Eight rats were underwent sham operation. Eighteen hours after CLP, hemodynamics and organ histological injuries were evaluated, peripheral blood mononuclear cells apoptosis and T-lymphocyte subsets counts were determined by flow cytometry, and the expression of p-Akt, Bcl-2, cleaved Caspase-3, and p-Erk1/2 in splenic CD4 + T-lymphocytes was determined by western blot and immunohistochemistry. β 1 -Adrenoreceptor expressions were evaluated using real-time polymerase chain reaction and immunohistochemistry. Results: Cecal ligation and puncture induced tachycardia, hypotension, hyperlactatemia, and multiple organ injury. Heart rate was unchanged in the CLP + E-5 group but decreased in the CLP + E-18 group. Hypotension, lactatemia, and multiple organ injuries were improved only in the CLP + E-5 group. T-lymphocyte apoptosis and T H 2/T H 1 ratio was decreased in CLP + E-5 but not in CLP + E-18. p-Akt and Bcl-2 expressions were increased, while cleaved Caspase-3 and p-Erk1/2 expressions were decreased in CLP + E-5. β 1 -Adrenoreceptor expressions were unchanged in both CLP + E-5 and CLP + E-18 groups. Conclusions: Low dose of esmolol reduced T-lymphocyte apoptosis and restored T H 2/T H 1 ratio in septic shock. Esmolol might modulate Akt/Bcl-2/Caspase-3 pathway to relieve T-lymphocyte apoptosis and inhibit Erk1/2 activity to decrease T H 0 differentiation to T H 2. Esmolol may be a potential immunoregulator of septic shock.

Study of the action of peripheral blood T-lymphocytes on renal cell carcinoma cells in model systems

Background. The introduction of immunotherapy based on immune checkpoint inhibitors has significantly improve the effectiveness of kidney cancer treatment. Nevertheless, not all patients respond to such treatment and there are no reliable predictive markers. Therefore, the development of a model system for assessing the cellular immune response to a tumor seems to be an urgent task.Aim. Development of a model to assess the T-cell immune response was the focus of this study.Materials and methods. Primary tumor cell culture and peripheral blood T-cell fraction were obtained under standard sterile conditions. T-cell activation were perform via anti-CD3 and anti-CD28 antibodies. The cell index was assessed using the RTCA xCELLigence biosensor technology (ACEA Biosciences, USA).Results. Tumor and T-cells from the same patient were cultured together to assess the growth rate of the tumor cell population. Measurements were taken at 30-minute intervals. The duration of observation was 24 hours. It has been shown that non-activated T-cells do not affect the proliferative properties of cultured cancer cells. On the contrary, activated T-cells suppressed the proliferative properties of cancer cells, which was associated with an increase in the proportion of Т-cells carrying the HLA-DR receptor (CD3+HLA–DR+) because of activation. Tumor-specific T-cell activity can lead to three consequences: lack of effect, partial suppression of proliferative properties, and complete death of tumor cells. In the latter case, the absence of such cells was determined by flow cytometry.Conclusion. The developed approach makes it possible to evaluate the cytotoxic properties of T cells in relation to tumor cells in a particular patient. The advantage of this method is that the measurement can be carried out in the presence of immune checkpoint inhibitors. The proposed method may be useful for evaluating the treatment regimen within the framework of personalized therapy.