Peripheral Immune Cell Subsets Research Articles

Abstract 1193: Peripheral immune analyses from phase I trial of HPV vaccine PRGN-2009 in combination with bintrafusp alfa in patients with HPV-associated cancers

Abstract Background: PRGN-2009 is a novel gorilla adenovirus vaccine targeting HPV16/18, and bintrafusp alfa (BA) is a bifunctional anti-PD-L1/TGFβ fusion protein. Patients with pretreated advanced HPV-associated malignancies received PRGN-2009 vaccine (5 × 1011 particle units, subcutaneous administration) q2 weeks for 3 administrations and biweekly 1200mg BA followed by q4 weeks vaccine and biweekly BA (NCT04432597), with an overall response rate of 30%. We report here correlative analyses from this first-in-human Phase I study using peripheral blood from 10 patients with HPV16+ (n=8), HPV18+ (n=1), or HPV45+ (n=1) disease to identify immune correlates associated with clinical response. Methods: Peripheral HPV-specific T cell responses, HPV circulating tumor DNA (ctDNA) from plasma, serum cytokines and soluble factors, and peripheral immune cell subsets were assessed to evaluate changes induced with treatment and peripheral correlates associated with clinical activity. Patients with complete response (CR, n=1), partial response (PR, n=2; 1 confirmed) or stable disease (SD, n=1) (n=4 total) were compared to patients with progressive disease (PD, n=6). Results: Eighty percent (8/10) of patients developed either HPV16 or HPV18-specific T-cell responses after repeat administration of PRGN-2009 with BA. Eight of 10 patients had detectable HPV16 or 18 ctDNA at baseline and changes in ctDNA load with treatment generally correlated with outcomes. Early transient increases in IL-8, TNFα, and IFNγ occurred, with greater increases in IL-8 at 2 weeks and TNFα at 4 weeks in patients with PD compared to CR/PR/SD. The patient who achieved a durable CR had HPV45+ disease, and had a) a 50% increase in CD8+ T cell frequency at 2 weeks, b) increases in frequencies of CD8+ naïve T cells expressing Ki67+ and central and effector memory T cells expressing 4-1BB, PD-1, or TIM-3, and c) considerable increases in HPV18-specific T cell responses through 484 days after treatment start, indicating durable antigen-specific T cell activity. Conclusions: The majority of patients developed HPV16/18 specific T-cell responses after repeat administration of PRGN-2009 in combination with BA. Transient increases in IL-8 and TNFα 2-4 weeks after start of treatment were associated with worse outcomes, suggesting that early changes in cytokines may reflect disease course. Furthermore, the early expansion of CD8+ T cell subsets in the patient developing a CR with HPV45+ disease after receiving a vaccine targeting HPV16 and HPV18 epitopes suggest a broadening and boosting of T cell responses that enabled potent anti-tumor activity. A high degree of homology between HPV18 and HPV45 may have contributed to the expansion of HPV18 specific T cells in the patient with CR. These data highlight the importance of assessing peripheral blood in immunotherapy trials to reveal important immunological phenomena. Citation Format: Meghali Goswami, Charalampos S. Floudas, Julius Strauss, Douglas E. Brough, Amy R. Lankford, Caroline Jochems, James L. Gulley, Jeffrey Schlom, Renee N. Donahue. Peripheral immune analyses from phase I trial of HPV vaccine PRGN-2009 in combination with bintrafusp alfa in patients with HPV-associated cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1193.

Variation of peripheral blood-based biomarkers for response of anti-PD-1 immunotherapy in non-small-cell lung cancer.

Immune checkpoint inhibitors (ICIs) for non-small-cell lung cancer (NSCLC) are on the rise, but unfortunately, only a small percentage of patients benefit from them in the long term. Thus, it is crucial to identify biomarkers that can forecast the efficacy of immunotherapy. We retrospectively studied 224 patients with NSCLC who underwent anti-PD-1 therapy. The role of biomarkers and clinical characteristics were assessed in a prognostic model. Only 14.3% of patients had both programmed death ligand 1 (PD-L1) and tumor mutational burden (TMB) outcomes, highlighting the need to investigate more available biomarkers. Our analysis found a correlation between histological PD-L1 TPS and hematological PD-1 expression. Analysis of hematological biomarkers revealed that elevated expression of CD4/CD8 and LYM% are positively associated with effective immunotherapy, while PD-1+ on T cells, NLR, and MLR have a negative impact. Moreover, high level of ΔCEA%, CYFRA21-1 and LDH may suggest ineffective ICIs. We also observed that disparate immunotherapy drugs didn't significantly impact prognosis. Lastly, by comparing squamous carcinoma and adenocarcinoma cohorts, ΔCEA%, CD3+PD-1+, CD4+PD-1+, and CD4/CD8 are more important in predicting the prognosis of adenocarcinoma patients, while age is more significant for squamous carcinoma patients. Our research has yielded encouraging results in identifying a correlation between immunotherapy's response and clinical characteristics, peripheral immune cell subsets, and biochemical and immunological biomarkers. The screened hematological detection panel could be used to forecast an NSCLC patient's response to anti-PD-1 immunotherapy with an accuracy rate of 76.3%, which could help customize suitable therapeutic decision-making.

Association of peripheral B cells and delirium: combined single-cell sequencing and Mendelian randomization analysis.

Delirium seriously affects the prognosis of patients and greatly reduces the ability to work and live. Peripheral inflammatory events may contribute to the development of delirium, the mechanism of which is still unclear. There is a lack of effective diagnostic and treatments for delirium in clinical practice. The study aims to investigate alterations in peripheral immune cell subsets under inflammatory stress and to explore causal associations with delirium. Single-cell transcriptional sequencing data of human peripheral blood mononuclear cells (PBMC) before and after lipopolysaccharide (LPS) intervention were processed by the Seurat package in R software. PBMC subsets and cellular markers were defined after downscaling and clustering by the Harmony algorithm to identify characteristic subsets in the context of inflammatory stress. Subsequently, a two-sample Mendelian randomization (MR) study was used to explore the causal associations of these inflammation-related PBMC subsets and their molecular phenotypes with delirium. Based on publicly available genetic data, the study incorporated 70 PBMC-associated immune traits, including 8 types of circulating immune cells, 33 B cell subsets and molecular phenotypes, 13 T cell subsets, and 16 B cell-associated cytokines. The results were also validated for robustness, heterogeneity, and horizontal pleiotropy. Under LPS-induced inflammatory stress, B cells, T cells, monocytes, and dendritic cells in human PBMC showed significant activation and quantitative changes. Of these, only lymphocyte and B cell counts were causally associated with delirium risk. This risk link is also seen in the TNF pathway. Further studies of B cells and their subsets revealed that this association may be related to unswitched memory B cells and CD27 expressed on memory B cells. Annotation of the screened SNPs revealed significant polymorphisms in CD27 and CD40 annotated by rs25680 and rs9883798, respectively. The functions of the key annotated genes may be related to the regulation of immune responses, cell differentiation, proliferation, and intercellular interactions. The present study revealed the potential possibility that B cell, memory B cell subset, and TNF-related molecules may be involved in the development of delirium due to peripheral inflammation, which can provide clues for further investigation of delirium prevention and treatment strategies.

P152 Longitudinal immune profiling of peripheral blood in patients with Ulcerative Colitis

Abstract Background Recent literature has established the communication and mutual influence between the gut and the brain, referred to as the gut-brain axis. While inflammatory bowel disease (IBD) poses a risk for neuroinflammation and brain dysfunction, the molecular mechanisms are not fully understood. This study aims to investigate longitudinal changes during Ulcerative Colitis (UC), focusing first on the characterization of peripheral immune cell subsets, circulating cytokines, and extracellular vesicles (EVs). Methods In our study, we examined 19 UC patients in both active (mean age in years: 45,63) and remission phases (mean age in years: 46,16). A gastroenterologist at the Gastroenterology Department from the Otto-von-Guericke University in Magdeburg, Germany assessed all participants, categorizing them into stages using Mayo scoring and calprotectin levels. We analysed peripheral whole blood and plasma samples using different flow cytometry-based approaches. Results Our findings indicate an upregulation of the neutrophil (CD16+, CD15+) numbers during the active stage followed by a significant reduction during remission, indicating an increase in innate inflammation as a first line of defence and a balanced state during remission. Classical (CD14+, CD16-) monocytes were decreased, along with similar results in the intermediate (CD14+, CD16+) subset. Nonclassical monocytes (CD14+, CD16++) increased from the active to the remission stage. Surface expression of activation marker CCR2 was downregulated for all monocyte subsets, whereas CX3CR1 was upregulated specifically in intermediate monocytes during remission. Compared to the active stage peripheral dendritic cell (CD14-, CD16-) numbers increase during remission suggesting less colonic infiltration. Peripheral regulatory T cells (Tregs) (CD127 low/-, CD25+), which are important for the reestablishment of homeostasis are upregulated during remission. Characterization of cytokine levels in plasma revealed an upregulation of the proinflammatory milieu during the active stage, especially with elevated IL-18 and TGF- β1 levels. Finally, those changes were accompanied by alterations of the surface markers expressed by isolated circulating EVs. Conclusion Our initial results indicate the feasibility of evaluating the gut-brain axis through liquid biopsy. We unravel the composition of the peripheral inflammatory milieu during the active phase. Currently we are focusing on the assessment of the CNS-derived metabolites and their bidirectional communication with the gastrointestinal system.

Repeated iv anti-CD20 treatment in multiple sclerosis: Long-term effects on peripheral immune cell subsets.

Repeated intravenous administration of anti-CD20 depleting monoclonal antibodies 6 months apart is among the highly effective treatment options in multiple sclerosis (MS). Here, we aimed to investigate peripheral immune cell subset depletion kinetics following either rituximab (RTX) or ocrelizumab (OCR) infusions in people with MS (pwMS). We studied pwMS treated de-novo with either RTX (n = 7) or OCR (n = 8). The examinations were scheduled before the initiation of anti-CD20 therapy and every 12 weeks for up to 15 months. Immunophenotyping of immune cell subsets in peripheral blood was performed by multiparametric fluorescence cytometry. A significant, persistent decrease of CD19+ B cells was observed already with the first anti-CD20 infusion (p < 0.0001). A significant proportional reduction of memory B cells within the B-cell pool was achieved only after two treatment cycles (p = 0.005). We observed a proportional increase of immature (p = 0.04) and naive B cells (p = 0.004), again only after the second treatment cycle. As for the peripheral T-cell pool, we observed a continuous proportional increase of memory T helper (TH) cells/central memory TH cells (p = 0.02/p = 0.008), while the number of regulatory T cells (Treg) decreased (p = 0.007). The percentage of B-cell dependent TH17.1 central memory cells dropped after the second treatment cycle (p = 0.02). No significant differences in the depletion kinetics between RTX and OCR were found. Peripheral immune cell profiling revealed more differentiated insights into the prompt and delayed immunological effects of repeated intravenous anti-CD20 treatment. The observation of proportional changes of some pathogenetically relevant immune cell subsets only after two infusion cycles deserves further attention.

The glycoimmune checkpoint receptor Siglec-7 interacts with T-cell ligands and regulates T-cell activation

Siglec-7 (sialic acid-binding immunoglobulin-like lectin 7) is a glycan-binding immune receptor that is emerging as a significant target of interest for cancer immunotherapy. The physiological ligands that bind Siglec-7, however, remain incompletely defined. In this study, we characterized the expression of Siglec-7 ligands on peripheral immune cell subsets and assessed whether Siglec-7 functionally regulates interactions between immune cells. We found that disialyl core 1 O-glycans are the major immune ligands for Siglec-7 and that these ligands are particularly highly expressed on naïve T-cells. Densely glycosylated sialomucins are the primary carriers of these glycans, in particular a glycoform of the cell-surface marker CD43. Biosynthesis of Siglec-7-binding glycans is dynamically controlled on different immune cell subsets through a genetic circuit involving the glycosyltransferase GCNT1. Siglec-7 blockade was found to increase activation of both primary T-cells and antigen-presenting dendritic cells invitro, indicating that Siglec-7 binds T-cell glycans to regulate intraimmune signaling. Finally, we present evidence that Siglec-7 directly activates signaling pathways in T-cells, suggesting a new biological function for this receptor. These studies conclusively demonstrate the existence of a novel Siglec-7-mediated signaling axis that physiologically regulates T-cell activity. Going forward, our findings have significant implications for the design and implementation of therapies targeting immunoregulatory Siglec receptors.

The clinical trajectory of peripheral blood immune cell subsets, T-cell activation, and cytokines in septic patients.

Changes in the immune status of patients with sepsis may have a major impact on their prognosis. Our research focused on changes in various immune cell subsets and T-cell activation during the progression of sepsis. We collected data from 188 sepsis patients at the First Affiliated Hospital of Zhejiang University School of Medicine. The main focus was on the patient's immunocyte subset typing, T-cell activation/Treg cell analysis, and cytokine assay, which can indicate the immune status of the patient. The study found that the number of CD4+ T cells, CD8+ T cells, NK cells, and B cells decreased early in the disease, and the decrease in CD4+ and CD8+ T cells was more pronounced in the death group. T lymphocyte activation was inhibited, and the number of Treg cells increased as the disease progressed. T lymphocyte inhibition was more significant in the death group, and the increase in IL-10 was more significant in the death group. Finally, we used patients' baseline conditions and immunological detection indicators for modeling and found that IL-10, CD4+ Treg cells, CD3+HLA-DR+ T cells, and CD3+CD69+ T cells could predict patients' prognosis well. Our study found that immunosuppression occurs in patients early in sepsis. Early monitoring of the patient's immune status may provide a timely warning of the disease.

The consensus of Chinese experts on refined analysis of immune cell subsets in peripheral blood by multi-parameter flow cytometry

The detection of immune cell subsets plays a very important role in the clinical diagnosis and treatment of various benign and malignant diseases and health management. In order to better carry out in-depth research on different functional immune cell subsets, establish reference intervals for clonality related indicators, establish special reference intervals for immune aging, individualized dynamic monitoring and treatment recovery, and discover the clinical significance of immune cells other than lymphocytes, it is urgent to analyze the peripheral blood immune cell subsets in a refined way. Multiparameter flow cytometry is an important technical method to detect immune cell subsets and evaluate immune function. In order to standardize the refined detection methods and protocols of peripheral blood immune cell subsets by flow cytometry, and further promote its application in clinical diagnosis and treatment of diseases and health management, Laboratory Medicine Committee of Chinese Association of Integrative Medicine (LMC-CAIM) organized experts to formulate this expert consensus.

CXCL10 Is Associated with Increased Cerebrospinal Fluid Immune Cell Infiltration and Disease Duration in Multiple Sclerosis.

Cerebrospinal fluid (CSF) is an important sampling site for putative biomarkers and contains immune cells. CXCL10 is a multiple sclerosis (MS)-relevant chemokine that is present in the injured central nervous system and recruits CXCR3+ immune cells toward injured tissues. Perform a comprehensive evaluation to determine a potential relationship between CXCL10 and various immune cell subsets in the CNS of MS and control cases. In MS and control cases, CXCL10 was measured in the CSF and plasma by ELISA. Immune cells within both the CSF and peripheral blood were quantified by flow cytometry. Compared to non-inflammatory neurological disease (NIND) cases, MS cases had significantly higher CXCL10 in CSF (p = 0.021); CXCL10 was also correlated with total cell numbers in CSF (p = 0.04) and T cell infiltrates (CD3+, p = 0.01; CD4+, p = 0.01; CD8+, p = 0.02); expression of CXCR3 on peripheral immune cell subsets was not associated with CSF CXCL10. Elevated levels of CXCL10 in the CSF of MS cases are associated with increased T cells but appear to be independent of peripheral CXCR3 expression. These results support the importance of elevated CXCL10 in MS and suggest the presence of an alternative mechanism of CXCL10 outside of solely influencing immune cell trafficking.

Cytokine and chemokine map of peripheral specific immune cell subsets in Parkinson’s disease

Peripheral immune cells play a vital role in the development of Parkinson’s disease (PD). However, their cytokine and chemokine secretion functions remain unclear. Therefore, we aimed to explore the cytokine and chemokine secretion functions of specific immune cell subtypes in drug-naïve patients with PD at different ages of onset. We included 10 early-onset and 10 late-onset patients with PD and age-matched healthy controls (HCs). We used mass cytometry to select specific immune cell subsets and evaluate intracellular cytokine and chemokine expression. Statistical tests included t-tests, analysis of variance, bivariate correlation analysis, and linear regression analysis. Compared with HCs, patients with PD exhibited significantly decreased intracellular pro-inflammatory cytokines and chemokines in selected clusters (e.g., tumor necrosis factor (TNF)-α, interleukin (IL)−8, IL-1β, and CC-chemokine ligand (CCL)17). Specific cytokines and cell clusters were associated with clinical symptoms. TNF-α played an important role in cognitive impairment. Intracellular TNF-α levels in the naïve CD8+ T-cell cluster C16 (CD57− naïve CD8+ T) and natural killer (NK) cell cluster C32 (CD57− CD28− NK) were negatively correlated with Montreal Cognitive Assessment scores. The C16 cluster affected cognitive function and motor symptoms. Increased TNF-α and decreased interferon-γ expression in C16 correlated with increased Unified Parkinson’s Disease Rating Scale III scores in patients with PD. In summary, we developed a more detailed cytokine and chemokine map of peripheral specific CD8+ T cell and NK cell subsets, which revealed disrupted secretory function in patients with PD and provided unique clues for further mechanistic exploration.

#5000 DIFFERENCES IN CIRCULATING IMMUNE CELLS PROFILE BETWEEN MALES WITH CARDIORENAL SYNDROME TYPE II AND CKD PATIENTS WITHOUT CARDIOVASCULAR DISEASE

Abstract Background and Aims Maladaptive activation of the immune system plays an important role in the pathogenesis of cardiovascular disease (CVD) and chronic kidney disease (CKD). The immune system components can act as mediators of organ cross-talk and may be involved in the reciprocal dysfunction that occurs in cardiorenal syndromes (CRS). The aim of our study was to investigate potential differences in blood levels of specific immune cells subsets between a cohort of type II CRS patients and CKD patients without established CVD. Method 40 stable male patients with CRS type II and 30 male CKD patients without CVD, matched for eGFR (CKD-EPI) were enrolled in this cross-sectional study. Exclusion criteria were history of malignancy, autoimmunity and active or chronic infections. The peripheral blood immune cell subsets CD14++CD16-, CD14++CD16+ and CD14+CD16++ absolute values and percentages out of total monocytes and NK cells (CD3+CD16+56+), CD3-CD19+ B lymphocytes, CD3+ CD4+ T cells, CD3+CD8+ T cells and Tregs (CD4+CD25+FoxP3+) absolute values and percentages out of total lymphocytes were measured by flow cytometry. Simultaneously, clinical, laboratory and echocardiographic data were assessed. Multiple regression analyses to assess independent relationships were performed by building separate models with each of the immune cells as the dependent variable and respective univariate correlates including patient group. Results Mean age of patients with CRS and CKD was 72±10 versus 66±10 years respectively (p = 0.01), mean eGFR was 37±14 and 33±16ml/min/1.73 m2 respectively (p = 0.28) and median urinary protein to creatine ratio (UPCR) was 0.19 (IQR, 0.10-0.52) versus 1.03 (IQR, 0.17-2.09) gr protein/gr creatinine (p = 0.02) respectively. CRS patients displayed increased levels of pro-inflammatory, intermediate CD14++CD16+ monocytes [41 (IQR, 24-78)/µL] compared to their CKD counterparts [35 (IQR, 18-43)/µL] (p = 0.04). A higher Tregs percentage was found in CRS patients [2.7% (IQR, 2.0%-3.9%)] compared to CKD patients [2.0% (IQR, 1.6%-2.6%)] (p = 0.03). Lower mean levels of lymphocytes were observed in CRS patients (1557±691/µL) compared to the CKD cohort (1920±545/µL) (p = 0.04). Finally, CRS patients displayed lower NK cell counts [148 (IQR, 103-258)/µL] compared to CKD patients [324 (IQR, 179-368)/µL] (p = 0.001). Age and UPCR did not correlate with immune cells subsets in the whole cohort, neither in the two groups separately. At multivariate regression analysis, the differences in immune cells between the two groups remained statistically significant. Specifically, in patients with CRS the intermediate CD14++CD16+ monocytes counts correlated positively with CRP (p = 0.002) and ESR (p = 0.02). A positive correlation was found between eGFR and total lymphocytes (p = 0.009), T cells (p = 0.005) and CD4+ T cells (p = 0.005) counts. The number and percentage of nonclassical CD14+CD16++ monocytes were higher in CRS patients with left ventricular ejection fraction (LVEF) less than 30% compared to patients with LVEF above 30% [33 (IQR, 18-37)/µL versus 13 (IQR, 10-29)/µL (p = 0.02) and 4.5% (IQR, 3.4%-7.2%) versus 2.7% (IQR, 1.9%-5.4%) (p = 0.03) respectively]. With regard to etiology, patients with dilated cardiomyopathy compared to patients with ischemic CVD displayed increased counts of intermediate CD14++CD16+ monocytes [75 (IQR, 41-104)/µL versus 36 (IQR, 22-61)/µL (p = 0.01)] and non-classical CD14+CD16++ monocytes [37 (IQR, 35-49)/µL versus 21 (IQR, 12-32)/µL (p = 0.02)]. Finally, NK cells and Tregs levels were lower in patients with atrial fibrillation compared to those without [133 (IQR, 79-173)/µL versus 260 (IQR, 151-314)/µL (p = 0.01)] and [32 (IQR, 21-43)/µL vs 47 (IQR, 34-85)/µL (p = 0.006)] respectively. Conclusion Patients with CRS type II exhibit alterations of the immune cells subsets profile in the peripheral blood compared to CKD patients of similar kidney function but without CVD. Our findings suggest that distinct immune mechanisms might be involved in the pathogenesis or the chronic course of CRS type II as compared to CKD. Future research is required to evaluate their pathophysiological or prognostic significance.

Immune Phenotype as a Biomarker for Systemic Lupus Erythematosus.

The treatment of rheumatoid arthritis was revolutionized with the use of molecular-targeted drugs that target immunoregulatory molecules. The success of treatment with these drugs prompted the development of molecular-targeted drugs for systemic lupus erythematosus. However, systemic lupus erythematosus is a disease with high heterogeneous immune abnormalities, and diverse cells or molecules can be treatment targets. Thus, the identification of subpopulations based on immune abnormalities is essential for the development of effective treatment. One analytical method used to identify subpopulations is the immunophenotyping of peripheral blood samples of patients. This analysis evaluates the validity of target molecules for peripheral blood immune cell subsets, which are expected to be developed as biomarkers for precision medicine in which appropriate treatment targets are set for each subpopulation.

Integration analysis of tumor metagenome and peripheral immunity data of diffuse large-B cell lymphoma.

It has been demonstrated that gut microbes are closely associated with the pathogenesis of lymphoma, but the gut microbe landscape and its association with immune cells in diffuse large B-cell lymphoma (DLBCL) remain largely unknown. In this study, we explored the associations between gut microbiota, clinical features and peripheral blood immune cell subtypes in DLBCL. A total of 87 newly diagnosed DLBCL adults were enrolled in this study. The peripheral blood samples were collected from all patients and then submitted to immune cell subtyping using full-spectral flow cytometry. Metagenomic sequencing was applied to assess the microbiota landscape of 69 of 87 newly diagnosed DLBCL patients. The microbiotas and peripheral blood immune cell subsets with significant differences between different National Comprehensive Center Network-International Prognostic Indexes (NCCN-IPIs) (low-risk, low-intermediate-risk, intermediate-high-risk, high-risk) groups were screened. A total of 10 bacterial phyla, 31 orders and 455 bacteria species were identified in 69 patients with newly diagnosed DLBCL. The abundances of 6 bacteria, including Blautia sp.CAG 257, Actinomyces sp.S6 Spd3, Streptococcus parasanguinis, Bacteroides salyersiae, Enterococcus faecalls and Streptococcus salivarius were significantly different between the low-risk, low-intermediate-risk, intermediate-high-risk and high-risk groups, among which Streptococcus parasanguinis and Streptococcus salivarius were markedly accumulated in the high-risk group. The different bacteria species were mostly enriched in the Pyridoxal 5'-phosphate biosynthesis I pathway. In addition, we found that 2 of the 6 bacteria showed close associations with the different immune cell subtypes which were also identified from different NCCN-IPIs. In detail, the abundance of Bacteroides salyersiae was negatively correlated with Treg cells, CD38+ nonrescue exhausted T cells, nature killer 3 cells and CD38+CD8+ effector memory T cells, while the abundance of Streptococcus parasanguinis was negatively correlated with HLA-DR+ NK cells, CD4+ Treg cells, HLA-DR+ NKT cells and HLA-DR+CD94+CD159c+ NKT cells. This study first reveals the gut microbiota landscape of patients with newly diagnosed DLBCL and highlights the association between the gut microbiota and immunity, which may provide a new idea for the prognosis assessment and treatment of DLBCL.

Changes of peripheral T cell subsets in melanoma patients with immune-related adverse events.

Immunotherapies have improved the prognosis of many cancer patients including patients with advanced melanoma. Immune checkpoint receptors including CTLA-4 and PD-1 have been established as main therapeutic targets for immunotherapy of melanoma. Although monotherapy is effective in melanoma patients, a dual therapy approach has been shown to be most effective. Dual checkpoint blockade, however, increases substantially the risk for immune-related adverse events (irAEs). In this study, we characterized peripheral immune cell subsets in patients with anti-PD-1 monotherapy and with dual immune receptors blockade targeting PD-1 and CTLA-4. We found differences in peripheral T cells between patients who developed severe immune-related side effects and patients with mild irAEs. We identified several mainly changes in CD8+ T cell subsets in patients with severe irAE under dual PD-1 and CTLA-4 blockade. This work suggests that peripheral immune cell dynamics could be associated with severe immune-related side effects in patients receiving immune checkpoint inhibitors. These changes could be used as future biomarkers in early diagnosis of irAEs.

Immunomics analysis of rheumatoid arthritis identified precursor dendritic cells as a key cell subset of treatment resistance

ObjectivesLittle is known about the immunology underlying variable treatment response in rheumatoid arthritis (RA). We performed large-scale transcriptome analyses of peripheral blood immune cell subsets to identify immune cells that...

Methamphetamine induces a low dopamine transporter expressing state without altering the total number of peripheral immune cells.

Methamphetamine is a widely abused psychostimulant and one of the main targets of dopamine transporter (DAT). Methamphetamine reduces DAT-mediated dopamine uptake and stimulates dopamine efflux leading to increased synaptic dopamine levels many folds above baseline. Methamphetamine also targets DAT-expressing peripheral immune cells, reduces wound healing and increases infection susceptibility. Peripheral immune cells such as myeloid cells, B cells and T cells express DAT. DAT activity on monocytes and macrophages exhibits immune suppressive properties via an autocrine paracrine mechanism, where deletion or inhibition of DAT activity increases inflammatory responses. In this study, utilizing a mouse model of daily single dose of methamphetamine administration, we investigated the impact of the drug on DAT expression in peripheral immune cells. We found in methamphetamine-treated mice that DAT expression was down-regulated in most of the innate and adaptive immune cells. Methamphetamine did not increase or decrease the total number of innate and adaptive immune cells but changed their immunophenotype to low-DAT-expressing phenotype. Moreover, serum cytokine distributions were altered in methamphetamine-treated mice. Therefore, resembling its effect in the CNS, in the periphery, methamphetamine regulates DAT expression on peripheral immune cell subsets, potentially describing methamphetamine regulation of peripheral immunity.

Artificial intelligence-based immunoprofiling serves as a potentially predictive biomarker of nivolumab treatment for advanced hepatocellular carcinoma.

Immune checkpoint inhibitors (ICI) have been applied in treating advanced hepatocellular carcinoma (aHCC) patients, but few patients exhibit stable and lasting responses. Moreover, identifying aHCC patients suitable for ICI treatment is still challenged. This study aimed to evaluate whether dissecting peripheral immune cell subsets by Mann-Whitney U test and artificial intelligence (AI) algorithms could serve as predictive biomarkers of nivolumab treatment for aHCC. Disease control group carried significantly increased percentages of PD-L1+ monocytes, PD-L1+ CD8 T cells, PD-L1+ CD8 NKT cells, and decreased percentages of PD-L1+ CD8 NKT cells via Mann-Whitney U test. By recursive feature elimination method, five featured subsets (CD4 NKTreg, PD-1+ CD8 T cells, PD-1+ CD8 NKT cells, PD-L1+ CD8 T cells and PD-L1+ monocytes) were selected for AI training. The featured subsets were highly overlapping with ones identified via Mann-Whitney U test. Trained AI algorithms committed valuable AUC from 0.8417 to 0.875 to significantly separate disease control group from disease progression group, and SHAP value ranking also revealed PD-L1+ monocytes and PD-L1+ CD8 T cells exclusively and significantly contributed to this discrimination. In summary, the current study demonstrated that integrally analyzing immune cell profiling with AI algorithms could serve as predictive biomarkers of ICI treatment.

Mass cytometry-based peripheral blood analysis as a novel tool for early detection of solid tumours: a multicentre study

ObjectiveEarly detection of a tumour remains an unmet medical need, and approaches with high sensitivity and specificity are urgently required. Mass cytometry time-of-flight (CyTOF) is a powerful technique to profile...

PD-1/PD-L1 immune-checkpoint blockade induces immune effector cell modulation in metastatic non-small cell lung cancer patients: A single-cell flow cytometry approach.

Peripheral immune-checkpoint blockade with mAbs to programmed cell death receptor-1 (PD-1) (either nivolumab or pembrolizumab) or PD-Ligand-1 (PD-L1) (atezolizumab, durvalumab, or avelumab) alone or in combination with doublet chemotherapy represents an expanding treatment strategy for metastatic non-small cell lung cancer (mNSCLC) patients. This strategy lays on the capability of these mAbs to rescue tumor-specific cytotoxic T lymphocytes (CTLs) inactivated throughout PD-1 binding to PD-L1/2 in the tumor sites. This inhibitory interactive pathway is a physiological mechanism of prevention against dangerous overreactions and autoimmunity in case of prolonged and/or repeated CTL response to the same antigen peptides. Therefore, we have carried out a retrospective bioinformatics analysis by single-cell flow cytometry to evaluate if PD-1/PD-L1-blocking mAbs modulate the expression of specific peripheral immune cell subsets, potentially correlated with autoimmunity triggering in 28 mNSCLC patients. We recorded a treatment-related decline in CD4+ T-cell and B-cell subsets and in the neutrophil-to-lymphocyte ratio coupled with an increase in natural killer T (NKT), CD8+PD1+ T cells, and eosinophils. Treatment-related increase in autoantibodies [mainly antinuclear antibodies (ANAs) and extractable nuclear antigen (ENA) antibodies] as well as the frequency of immune-related adverse events were associated with the deregulation of specific immune subpopulations (e.g., NKT cells). Correlative biological/clinical studies with deep immune monitoring are badly needed for a better characterization of the effects produced by PD-1/PD-L1 immune-checkpoint blockade.

Association of immune cell subsets with incident heart failure in two population-based cohorts.

Circulating inflammatory markers are associated with incident heart failure (HF), but prospective data on associations of immune cell subsets with incident HF are lacking. We determined the associations of immune cell subsets with incident HF as well as HF subtypes [with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF)]. Peripheral blood immune cell subsets were measured in adults from the Multi-Ethnic Study of Atherosclerosis (MESA) and Cardiovascular Health Study (CHS). Cox proportional hazard models adjusted for demographics, HF risk factors, and cytomegalovirus serostatus were used to evaluate the association of the immune cell subsets with incident HF. The average age of the MESA cohort at the time of immune cell measurements was 63.0±10.4years with 51% women, and in the CHS cohort, it was 79.6±4.4years with 62% women. In the meta-analysis of CHS and MESA, a higher proportion of CD4+ T helper (Th) 1 cells (per one standard deviation) was associated with a lower risk of incident HF [hazard ratio (HR) 0.91, (95% CI 0.83-0.99), P=0.03]. Specifically, higher proportion of CD4+ Th1 cells was significantly associated with a lower risk of HFrEF [HR 0.73, (95% CI 0.62-0.85), <0.001] after correction for multiple testing. No association was observed with HFpEF. No other cell subsets were associated with incident HF. We observed that higher proportions of CD4+ Th1 cells were associated with a lower risk of incident HFrEF in two distinct population-based cohorts, with similar effect sizes in both cohorts demonstrating replicability. Although unexpected, the consistency of this finding across cohorts merits further investigation.