Expression Of CD86 Research Articles

Construction of an Innovative Nanogel and Its Applications for Achieving Chemo-Immunotherapy of Tumors.

Malignant tumors, also known as cancers, are a global public health problem. Nanogels are promising carriers for the delivery of anticancer medicines. Therefore, based on the unique microenvironment of tumor cells and the advantages of nanogels, a simple and economical one-pot synthesis method was designed to construct natural polysaccharide-based redox-responsive nanogels (LDD NGs). The enhanced permeability and retention (EPR) effect enriched LDD NGs in tumor cells, which then rapidly collapsed and released the natural antitumor drug diosgenin (DG) and the natural polysaccharide lentinan (LNT) via the depletion of a high level of reduced glutathione (GSH) in tumor cells, resulting in a synergistic therapeutic effect of chemotherapy and immunotherapy. In vivo antitumor experiments showed that LDD NGs could inhibit the proliferation and metastasis of the A549 lung cancer cells. Further studies indicated that LDD NGs could increase the production of ROS and induce apoptosis of A549 cells. In addition, LNT released from LDD NGs could promote the proliferation of dendritic cells, increase the production of NO, and upregulate the expressions of the costimulatory molecules CD40, CD80, CD86, and MHC-II. The construction of LDD NGs was a novel drug synthesis approach that could provide fresh ideas for the development of polysaccharide-based redox-responsive drug delivery systems.

Stretched Vascular Endothelial Cells Polarized Neutrophils to N2 Type via TRPC1-IL13-STAT3 Axis.

VECs play a crucial role in regulating the function of neutrophils, which is essential for immune responses and inflammation. As stretch-sensitive cells, VECs sense mechanical stretch through surface mechanoreceptors, converting external mechanical stimuli into biochemical signals. This study aimed to explore the molecular mechanisms underlying the regulation of neutrophil behavior by stretched VECs. The key cytokine-inducing neutrophil N2 polarization in the conditioned medium from stretched vascular endothelial cells (CM-stretch) was validated through multifactorial matrix and flow cytometry. Additionally, the molecular mechanism underlying the response of vascular endothelial cells to stretch was systematically verified through layer-by-layer analysis using WB. IL13, not IL4, was ultimately identified as a key cytokine-inducing neutrophil N2 polarization in CM-stretch. Inhibition of the transient receptor potential channel (TRPC1) and siRNA-mediated knockdown of TRPC1 both significantly decreased IL13 production. Furthermore, neutralizing IL13 in the CM-stretch or inhibiting STAT3 phosphorylation inhibited neutrophil N2 polarization, as evidenced by reduced CD206 and VEGFA expression. These results demonstrate that stretched VECs initiate a signaling cascade that induces neutrophil N2 polarization through the TRPC1-IL13-STAT3 axis, suggesting that mechanical stretching of VECs could shift neutrophil function from a pro-inflammatory to a more regulatory and healing role.

Lymphoid Aggregates in Canine Cutaneous and Subcutaneous Sarcomas: Immunohistochemical and Gene Expression Evidence for Tertiary Lymphoid Structures.

Canine cutaneous/subcutaneous soft-tissue sarcomas (STS) are diversely derived mesenchymal neoplasms with a risk of recurrence and/or metastasis depending on the extent of surgical excision and histologic grade. Lymphoid aggregates (LAs) are often described in these tumours but not characterised. In humans, LA characterised as tertiary lymphoid structures (TLSs) improve the prognosis of many tumours, including sarcomas. We sought to determine if LA meeting a size criterion (> 700 cells) in canine sarcomas met the criteria of TLS and the overall prevalence of LA of any size. RNA expression in large LAs versus aggregate-adjacent sarcoma tissue (AAS) was measured in laser capture microdissected tissue and compared to curl-derived RNA from aggregate-free sarcomas and lymph nodes. CD3, CD20, MUM-1 and PNAd expressions were measured using immunohistochemistry. CD20 and CD3 mRNA were more highly expressed in LA versus AAS (13.8 fold, p = 0.0003 and 2.3 fold, p = 0.043). This was supported by the IHC findings. The large LAs were also enriched in chemokine RNA expression characteristic of TLS (CXCR5 5.8 fold, p < 00001, CCL19 3.68 fold, p = 0.0209, CCL21 6.87 fold, p = 0.0209 and CXCL13 2.68 fold, p = 0.0924). Plasma cells and high endothelial venules were identified in LA containing tumours but not in control tissue. Large LAs were present in 12% of tumours, and LA of any size in 30%. We conclude that large LAs in canine STS are consistent with TLS.

Causality of immune cells and endometriosis: a bidirectional mendelian randomization study

BackgroundEndometriosis, a prevalent chronic condition, afflicts approximately 10% of women in their reproductive years. Emerging evidence implicates immune cells in the pathogenesis of endometriosis, particularly in angiogenesis, tissue proliferation, and lesion invasion. This investigation employs two-sample Mendelian Randomization (MR) to dissect the bidirectional causal relationships between immune cell profiles and endometriosis.MethodsWe leveraged publicly available genome-wide association study (GWAS) data to elucidate the causal interplay between immune cell traits and endometriosis. Utilizing GWAS summary statistics ranging from accession numbers GCST90001391 to GCST90002121 and endometriosis data from the FinnGen study GWAS (8,288 endometriosis cases and 68,969 controls), we adopted stringent criteria for instrumental variable selection. We applied MR-Egger, weighted median, inverse variance weighted (IVW), and weighted mode methods to derive causal estimates. To address potential heterogeneity and pleiotropy, Cochran’s Q test, MR-Egger intercept, and leave-one-out analyses were executed. Reverse-direction MR and bidirectional MR analyses evaluated potential reciprocal causation and the influence of endometriosis on immune cell composition.ResultsOur analysis identified five immune phenotypes inversely associated with endometriosis risk. These phenotypes comprise: a percentage of CD11c + HLA-DR + + monocytes, CD25 expression on CD39 + CD4 + T cells, elevated CD25 on CD45RA + CD4 + non-regulatory T cells, HLA-DR intensity on HLA-DR + CD8 bright (CD8br) T cells, and the proportion of naïve double-negative (CD4 − CD8− %DN) T cells. In contrast, eleven phenotypes were positively correlated with endometriosis risk, including: CD127 expression on T cells, the proportion of CD24 + CD27 + B cells within lymphocytes, CD25 expression on CD28 + CD4 + T cells, CD28 expression on CD39 + activated regulatory T cells (activated Tregs), the frequency of bright CD33 HLA-DR + CD14 − cells within the CD33br HLA-DR + compartment, CD45 expression on lymphocytes and natural killer (NK) cells, activation status of central memory CD8 bright (CM CD8br) T cells, CX3CR1 expression on monocytes, and the percentage of HLA-DR + NK cells within the NK cell subset. Sensitivity assessments that excluded significant heterogeneity and pleiotropy confirmed the stability of these associations, thereby reinforcing the validity of our findings.ConclusionThis study provides novel evidence of the potential causal impact of specific immune cells on the risk of developing endometriosis. These findings enhance our understanding of endometriosis pathophysiology and may inform innovative approaches for its diagnosis and management. While our findings provide novel insights, limitations such as potential horizontal pleiotropy and reliance on European ancestry data should be considered. Future research should expand to diverse populations and incorporate individual-level data to refine these findings.

Treatment with oclacitinib, a Janus kinase inhibitor, down-regulates and up-regulates CD25 and Foxp3 expression, respectively, in peripheral blood T cells of dogs with atopic dermatitis

BackgroundOclacitinib (OCL), a Janus kinase inhibitor, is a novel immunomodulatory/immunosuppressive agent which is an approved as the first-line treatment for atopic dermatitis (AD) in dogs. The aim of the study was to investigate the effects of OCL on CD4+ and CD8+ T cells and their selected subsets under clinical conditions, i.e. in dogs suffering from AD, in terms of both safety and immune mechanisms underlying its therapeutic actions. Eight dogs were treated for 28 days with OCL at the recommended dose. Blood samples were taken at day 0, 7, 14 and 28.ResultsThe study showed that the mean percentage and absolute count of CD4+ and CD8+ T cells on the 14th and 28th day of the treatment with OCL did not differ from the corresponding baseline values, i.e. those before the treatment. On the 7th day of the treatment, the mean absolute count of CD4+ T cells and the mean percentage and absolute count of CD8+ T cells were significantly increased. The research found that on the 14th day of the treatment, the mean percentage and absolute count of CD25+CD4+ and CD25+CD8+ T cells were significantly decreased; the reduction in the percentage of CD25+CD4+ T cells persisted on 28th day of the treatment. A two-week treatment with OCL resulted in an increase in the mean percentage of Foxp3+CD4+ T cells, and this effect was sustained at the last time point. The treatment with OCL decreased the eosinophil level but does not affect the absolute counts of basophils, monocytes and neutrophils.ConclusionsThe findings of the study strongly suggest that: (a) in terms of the impact of OCL on the number of PB CD4+ and CD8+ T cells, monthly treatment with the drug should be considered as a relatively safe; (b) the eosinophil-reducing effect and the down-regulation of the AD up-regulated CD25 expression on CD4+ Teff cells may constitute significant elements of the mechanism of action underlying the therapeutic effects of the drug in the treatment of canine AD; (c) the generation of inducible Foxp3-expressing CD4+ regulatory T cells - resulting in the shift of the CD4+ Treg cell (i.e. Foxp3+CD4+)/activated Teff (i.e. CD25+CD4+) cell balance toward an increased proportion of Treg cells - may be considered as additional mechanism involved in producing the immunomodulatory/immunosuppressive properties of OCL.

Tectochrysin Alleviates Periodontitis by Modulating M2/M1 Macrophage Ratio and Oxidative Stress Via Nuclear Factor Kappa B/Heme Oxygenase-1/Nuclear Factor Erythroid 2-Related Factor 2 Pathway

ABSTRACT Background Tectochrysin suppresses several diseases. In this study, we aimed to explore the effects of tectochrysin ona rat model of periodontitis PDS). Methods Male Sprague-Dawley (SD) rats were subjected to ligature to induce periodontitis. Bone parameters were analyzed using micro-computed tomography and periodontal tissues were evaluated using Masson’s, hematoxylin and eosin, and tartrate-resistant acid phosphatase staining. The expression of HO-1, Nrf2, CD206, Arg-1, and iNOS was evaluated using immunohistochemistry. Malondialdehyde (MDA), reduced glutathione (GSH), and superoxide dismutase (SOD) levels and IL-1β, IL-6, and tumor necrosis factor (TNF)-α,and NF-κB and Nrf2/HO-1 were analyzed. Results Tectochrysin reduced alveolar bone loss, promoted new bone formation, and inhibited osteoclast formation in periodontitis rats. It decreased the number of inflammatory cells and the levels of IL-1β, IL-6, and TNF-α, indicating a reduction in inflammation. Tectochrysin restored the Arg-1/iNOS ratio, indicating M2 macrophage polarization, and inhibited the NF-kB pathway. Tectochrysin restored GSH and SOD levels, inhibited MDA content, and activated the HO-1/Nrf2 pathway. Conclusion Tectochrysin alleviates PDS in rats by modulating the M2/M1 macrophage ratio via the NF-kB pathway and suppressing oxidative stress via the HO-1/Nrf2 pathway.

Assessment of Gene Expression of Some Human Cluster of Differentiation in Chronic HCV Patients

Background: Hepatitis C virus (HCV) is one of the most potential pathogens all over the world. It is one of the main causes of chronic liver diseases. The host immune response against HCV sets off a chain reaction that results in liver damage after HCV infection in addition to necrosis and cellular inflammation, fibrosis, and hepatocellular carcinoma. Objective: This study aimed at evaluation of gene expression of human cluster of differentiation (CD25, CD39 and CD127) in patients with chronic HCV infection. Materials and Methods: The study involved 70 HCV patients who were diagnosed in Hepatology and Gastroenterology Center at Azadi Teaching Hospital and 50 control subjects during October 2023 until April 2024. HCV patients were confirmed with real time PCR. In addition RNA extraction was conducted on patients and control whole blood to assess the gene expression of CD25, CD39 and CD127 in both groups. Result: Regarding gene expression of CD25, CD39 and CD127, our data revealed significant overexpression of those marker in HCV patients in comparison to control group with P value (0.0001, &lt;0.0001 and &lt;0.0001) respectively. Conclusion: The gene expression of CD25, CD39 and CD127 were significantly up-regulated in HCV patients compared to healthy control indicating the role played by these markers.

How Co-Stimulatory/Inhibitory Molecules Vary Across Immune Cell Subtypes in the Severity of Systemic Lupus Erythematosus Compared to Controls

Background: Co-stimulatory and co-inhibitory molecules are critical to T cell responses and involved in the pathogenesis of systemic lupus erythematosus (SLE). This study aimed to comprehensively analyze the surface expression of these molecules in various phenotypic immune cells, comparing the differences between various levels of the severity in SLE and control groups. Methods: Peripheral blood mononuclear cells (PBMCs) were isolated using Ficoll-Paque from blood samples of severe SLE patients (treatment with immunosuppressants), mild SLE patients (excluding those with persistent proteinuria or thrombocytopenia), and healthy controls (n = 10 each). PBMCs were stimulated for 48 h. The cells were stained with anti-CD3, CD4, CD28, PD-1, and CTLA-4 antibodies and analyzed by flow cytometry. Differences between groups were assessed using the Kruskal–Wallis test and Mann–Whitney U-test, with median values and statistical significance (p &lt; 0.05) reported. Results: The results showed that CD28 expression was significantly higher in SLE patients compared to controls, with the highest levels in mild SLE. However, CD3+ CD28+ and CD4+ CD28+ cells were more prevalent in controls (p = 0.032 and 0.017, respectively). Mild SLE patients exhibited the highest CTLA-4 expression, with significant differences from severe SLE and controls (p = 0.030 and 0.037, respectively). PD-1 expression was lowest in severe SLE but highest in mild SLE within CD3+ CD4+ cells (p = 0.001). After 48 h of activation, CD4+ CTLA4+ and CD3+ CTLA4+ expression levels were significantly higher in controls compared to SLE groups. Conclusions: Our study highlighted that the expression of CD28, CTLA-4, and PD-1 in lymphocytes and specific T cell subsets was various according the severity of SLE in patients, underscoring their roles in disease pathogenesis.

Moxibustion Regulates the Expression of T Cells in Rheumatoid Arthritis Through Tim-3/Gal-9 Signaling Pathway.

To observe the effects of moxibustion on T cells and T cell immunoglobulin and mucin-domain-containing molecule-3/galectin-9 (Tim-3/Gal-9) pathway in rats with rheumatoid arthritis (RA). To further explore the possible anti-inflammatory mechanism of moxibustion in the treatment of RA. Thirty Sprague Dawley rats were randomly divided into three groups, including a control group, an RA model group, and a moxibustion group. An RA model was created through the injection of Freund's complete adjuvant. In the moxibustion group, rats were treated with moxibustion at acupoints of "Shenshu" and "Zusanli." A total of three courses of treatment were conducted. Then the thickness of foot pad was measured, joint pathological changes were observed by hematoxylin-eosin (HE) staining, the proportion of CD4+T and CD8+T in peripheral blood was detected by flow cytometry, the expression levels of Tim-3 and Gal-9 in synovium were detected by polymerase chain reaction (PCR), and the expressions of CD4+T and CD8+T in synovium were detected by immunofluorescence. HE staining showed that the synovial tissue of the control group was smooth and neatly arranged without inflammatory cell infiltration. In the model group, the joint space was narrowed, the synovial tissue had congestion and edema, and a large number of inflammatory cells infiltrated. Compared with the model group, in the moxibustion group, the joint space narrowed with synovium hyperemia and edema, and the level of inflammatory cell infiltration decreased. Flow cytometry showed that compared with the model group, CD4+T expression in the moxibustion group was downregulated, while CD8+T expression was upregulated. PCR results showed that compared with the model group, the expressions of Tim-3 and Gal-9 in the moxibustion group were upregulated. Immunofluorescence results showed that compared with the model group, CD4+T expression in the moxibustion group was decreased, while CD8+T expression was increased. The results demonstrate that moxibustion not only suppressed the expression of CD4+T but also promoted the expression of CD8+T. The anti-inflammatory effect of moxibustion may be related to the regulation of T cell expression through the Tim-3/Gal-9 signaling pathway.

Bacteriophage–derived double-stranded RNA (larifan) exerts variable effects on human blood monocytes depending on age and sex of donors

To date, great attention is paid to sex and age differences in the therapeutic effectiveness of drugs, including those that impact the immune system. Bacteriophage-derived dsRNA is the main component of the medicinal product Larifan, which exhibits interferonogenic activity. This study aimed to estimate the effect of Larifan on the activation status of human peripheral blood monocytes collected from donors of different ages and sex. Blood samples were obtained from the healthy volunteers, divided into 4 groups: young men and young women aged from 20 to 39 years, aged men and aged women from 54 to 69 years old. EDTA-anticoagulated blood samples were exposed to 200 μg/ml Larifan for 30 min, cells were washed and treated to study phagocytic index, ROS generation and expression of phenotypic markers. Only live monocytes selected by flow cytometry were included in the analysis. It was shown that monocytes from young as well as from aged females turned out to be quite inert to the treatment with Larifan. Monocytes from young males after the treatment demonstrated a minor decrease in phagocytic activity and significant down-regulation of ROS generation. Monocytes from aged adults showed clear sex-based differences in the basal cell phenotype. Thus, compared to monocytes from women, the monocytes from men over 50 after the treatment with Larifan showed decreased phagocytic activity and CD86 expression along with increased CD206 expression. Taken together, these results indicate the need for further studies of Larifan focused on developing personalized treatment depending on the age and sex of an individual. Keywords: double-stranded RNA, Larifan, monocytes, phagocytosis, reactive oxygen species, sex and age differences

Clinical significance of CD155 expression in surgically resected lung squamous cell carcinoma.

Cluster of differentiation 155 (CD155) is expressed in many tumor types. CD155 is involved in the immune avoidance of tumor cells and contributes to tumor development and progression. Therefore, CD155 is a novel target for cancer immunotherapy. The clinical significance of CD155 expression in lung squamous cell carcinoma (LUSC) has not been fully elucidated. We performed a retrospective analysis of 264 patients with surgically resected LUSC. Immunohistochemistry was used to evaluate CD155 expression. The association of CD155 expression with clinicopathological features and clinical outcomes was assessed. We also analyzed the relationship between CD155 expression and programmed cell death-ligand 1 (PD-L1) expression and tumor-infiltrating lymphocytes. Among the 264 patients, 137 patients (51.9%) were classified in the high CD155 expression group. High CD155 expression was significantly associated with pleural invasion, vascular invasion, PD-L1 positivity, and high CD3, CD4, and CD8 expressions. In multivariate analysis, the presence of pleural invasion and PD-L1 positivity were independent predictors of high CD155 expression. Kaplan-Meier curve analysis showed that high CD155 expression was significantly associated with shorter disease-free survival and overall survival. In multivariate analysis, high CD155 expression was an independent poor prognostic factor for overall survival, but not for disease-free survival. Subgroup analyses revealed that the prognostic effect of CD155 expression was observed in the PD-L1 positive group but not the PD-L1 negative group. Our analysis revealed that high CD155 expression significantly predicted poor prognosis in patients with surgically resected LUSC, especially in patients with PD-L1-positive tumors.

Enhanced immunomodulatory properties of ovalbumin through transglutaminase and tyrosinase/caffeic acid-catalyzed crosslinking plus galactomannan conjugation alleviates allergic asthma

Ovalbumin (OVA) is the primary allergenic protein, associated with T helper 2 (Th2)-mediated allergy reactions. Here, we studied OVA’s conformational structure, digestibility, and allergenic potency upon galactomannan (Man) conjugation along with transglutaminase-catalyzed crosslinking (TG-Man/OVA) and tyrosinase/caffeic acid-catalyzed crosslinking (Tyr-Man/OVA). Enzymatic glycosylation altered OVA’s conformation and enhanced the gastrointestinal digestibility. Stimulation of bone marrow-derived dendritic cells (BMDCs) with enzymatically glycosylated OVA reduced the expression of CD40, CD80, CD86 and MHC class II molecules. Furthermore, glycosylated OVA increased IL-10 production while suppressing proinflammatory cytokine production in BMDCs. In an OVA-induced mouse asthma model, TG-Man/OVA and Tyr-Man/OVA upregulated IFN-γ and IL-10 expression and downregulated IL-4, IL-5, and IL-13 in lungs. Crosslinked OVA diminished infiltrated cells in bronchoalveolar lavage fluid and lung and attenuated eosinophilic airway inflammation. These findings offer valuable insights into the development of a novel product with improved hypoallergenic and immunomodulatory properties and hold promise in attenuating allergic diseases.

Transgelin 2 guards T cell lipid metabolism and antitumour function.

Mounting effective immunity against pathogens and tumours relies on the successful metabolic programming of T cells by extracellular fatty acids1-3. Fatty-acid-binding protein 5 (FABP5) has a key role in this process by coordinating the efficient import and trafficking of lipids that fuel mitochondrial respiration to sustain the bioenergetic requirements of protective CD8+ T cells4,5. However, the mechanisms that govern this immunometabolic axis remain unexplored. Here we report that the cytoskeletal organizer transgelin 2 (TAGLN2) is necessary for optimal fatty acid uptake, mitochondrial respiration and anticancer function in CD8+ T cells. TAGLN2 interacts with FABP5 to facilitate its cell surface localization and function in activated CD8+ T cells. Analyses of ovarian cancer specimens revealed that endoplasmic reticulum (ER) stress responses induced by the tumour microenvironment repress TAGLN2 in infiltrating CD8+ T cells, thereby enforcing their dysfunctional state. Restoring TAGLN2 expression in ER-stressed CD8+ T cells increased their lipid uptake, mitochondrial respiration and cytotoxic capacity. Accordingly, chimeric antigen receptor T cells overexpressing TAGLN2 bypassed the detrimental effects of tumour-induced ER stress and demonstrated therapeutic efficacy in mice with metastatic ovarian cancer. Our study establishes the role of cytoskeletal TAGLN2 in T cell lipid metabolism and highlights the potential to enhance cellular immunotherapy in solid malignancies by preserving the TAGLN2-FABP5 axis.

Expression of Molecules Characterizing Metabolic and Cytotoxic Activity of Natural Killer Different Subpopulations of Peripheral Blood During Pregnancy

The functions of peripheral blood NK cells change significantly during pregnancy, which is mainly due to the inhibition of their cytotoxicity. The functional activity of NK cells is directly related to their metabolic status, but these changes in physiological pregnancy have not been studied. The aim of this work is to study the expression of Glut-1, CD94 and CD107a molecules characterizing metabolic and cytotoxic activity, as well as the mitochondrial mass of different subpopulations of peripheral blood NK cells in the I and III trimesters of physiological pregnancy. The object of the study was the peripheral blood of healthy women in the I and III trimesters of physiological pregnancy. The control group consisted of healthy non-pregnant women in the follicular phase of the menstrual cycle. The expression of Glut-1, CD94, CD107a molecules and the mitochondrial mass were analyzed by flow cytometry on regulatory (CD16–CD56bright), cytotoxic (CD16+CD56dim), minor cytotoxic (CD16hiCD56–) NK cells. It was found that in non-pregnant women, minor cytotoxic CD16hiCD56–NK have the highest expression of Glut-1, CD107a and the lowest expression of CD94 compared to other NK cell subpopulations. On regulatory CD16–CD 56bright and cytotoxic CD16+CD56dimNK, the expression of these molecules is comparable to each other. The mitochondrial mass is similar in all studied subpopulations. In the first trimester, the expression of Glut-1 increases on regulatory CD16–CD56brightNK, the mitochondrial mass and the expression of CD94, CD107a in all NK cells do not differ from non-pregnant ones. In the third trimester, the mitochondrial mass increases in cytotoxic CD16+CD56dimNK cells, but CD94 expression decreases compared to non-pregnant ones, and the expression CD94 in regulatory CD16–CD56brightNK increases compared to the first trimester. CD107a expression in minor cytotoxic CD16hiCD56–NK decreases, but in other subpopulations does not change compared to non-pregnant. The expression of Glut-1 does not change in all subpopulations. Thus, different subpopulations of peripheral blood NK cells are heterogeneous in the expression of Glut-1, CD107a, CD94. The expression of these molecules during physiological pregnancy varies by trimester. The obtained results are important for understanding the mechanisms of NK cell function regulations during pregnancy.

The Role of miR-155 in Modulating Gene Expression in CD4+ T Cells: Insights into Alternative Immune Pathways in Autoimmune Encephalomyelitis

CD4+ T cells are considered the main orchestrators of autoimmune diseases. Their disruptive effect on CD4+ T cell differentiation and the imbalance between T helper cell populations can be most accurately determined using experimental autoimmune encephalomyelitis (EAE) as an animal model of multiple sclerosis (MS). One epigenetic factor known to promote autoimmune inflammation is miRNA-155 (miR-155), which is significantly upregulated in inflammatory T cells. The aim of the present study was to profile the transcriptome of immunized mice and determine their gene expression levels based on mRNA and miRNA sequencing. No statistically significant differences in miRNA profile were observed; however, substantial changes in gene expression between miRNA-155 knockout (KO) mice and WT were noted. In miR-155 KO mice, mRNA expression in CD4+ T cells changed in response to immunization with the myeloid antigen MOG35-55. After restimulation with MOG35-55, increased Ffar1 (free fatty acid receptor 1) and Scg2 (secretogranin-2) expression were noted in the CD4+ T cells of miR-155-deficient mice; this is an example of an alternative response to antigen stimulation.

Causal association of immune cells and endometritis: a Mendelian randomization study

Research exploring the link between immune cell profiles and the development of endometritis remains scant. This gap necessitates further study to decode the complex interrelations influencing this condition. In this analysis, we leveraged two-sample Mendelian randomization to examine the causal ties between the phenotypes of immune cells and the incidence of endometritis. Our evaluation hinged on data from 3757 participants hailing from Sardinia, focusing on a diverse array of 731 immune phenotypes, and cross-referenced with endometritis data sourced from the UK Biobank. To ensure rigor, we performed sensitivity analyses, utilized MR-Egger and MR-Presso to check for pleiotropy, and applied Cochran’s Q test for assessing the heterogeneity of our findings. Our investigation identified numerous immune characteristics associated with endometritis. For certain immune traits, a lower risk of endometritis was observed, including: Absolute Counts of CD39 + CD4 + T cells, CD25 + CD39 + CD4 regulatory T cells, and CD25 + + CD8 + T cells; Absolute Counts of Switched Memory B cells; CD19 expression on IgD + CD38dim and Switched Memory B cells; CD20 expression on IgD + CD38− Unswitched Memory B cells; percentage of Switched Memory B cells among lymphocytes; CD16-CD56 expression on HLA DR + Natural Killer cells; percentage of CD11c + CD62L− monocytes; CD86 expression on monocytes; CCR2 expression on CD14 + CD16 + monocytes; and CD14 expression on Monocytic Myeloid-Derived Suppressor Cells, with Odds Ratios (ORs) between 0.413 and 0.703. On the contrary, increased risks of endometritis were linked with: the percentage of Effector Memory CD4 + T cells within the CD4 + T cell population; percentages of HLA DR + T cells and HLA DR + CD8 + T cells among T cells; CD4 expression on CD28 + CD4 + T cells; CD20 expression on CD20- CD38- B cells; percentage of IgD + CD24 + B cells within the B cell population; CD62L expression on CD62L + myeloid Dendritic Cells; and Absolute Counts of Plasmacytoid Dendritic Cells, with ORs from 1.473 to 2.677, indicating these traits potentially elevate the risk of developing endometritis. Our research delineates distinct causal links between specific immune cell phenotypes and endometritis, offering new perspectives that could contribute to the pinpointing of new therapeutic avenues for this condition.

Epstein-Barr virus infection induces tissue-resident memory T cells in mucosal lymphoid tissues.

EBV contributes to around 2% of all tumors worldwide. Simultaneously, more than 90% of healthy human adults persistently carry EBV without clinical symptoms. In most EBV carriers, it is thought that virus-induced tumorigenesis is prevented by cell-mediated immunity. Specifically, memory CD8+ T cells recognize EBV-infected cells during latent and lytic infection. Using a symptomatic primary infection model, similar to infectious mononucleosis (IM), we found EBV-induced CD8+ tissue resident memory T cells (TRMs) in mice with a humanized immune system. These human TRMs were preferentially established after intranasal EBV infection in nasal-associated lymphoid tissues (NALT), equivalent to tonsils, the primary site of EBV infection in humans. They expressed canonical TRM markers, including CD69, CD103, and BLIMP-1, as well as granzyme B, CD107a, and CCL5. Despite cytotoxic activity and cytokine production ex vivo, these TRMs demonstrated reduced CD27 expression and proliferation and failed to control EBV viral loads in the NALT during infection, although effector memory T cells (TEMs) controlled viral titers in spleen and blood. Overall, TRMs are established in mucosal lymphoid tissues by EBV infection, but primarily, systemic CD8+ T cell expansion seems to control viral loads in the context of IM-like infection.

The prognostic and therapeutic value of the tumor microenvironment and immune checkpoints in pancreatic neuroendocrine neoplasms

Pancreatic neuroendocrine neoplasms (Pan-NEN) represent a group of highly heterogeneous cancers, characterized by complex and diverse biological behavior. The objective of this study was to systematically investigate the immunological features of the tumor microenvironment (TME) in Pan-NEN, aiming to identify prognostic biomarkers and explore the therapeutic potential of immunotherapy for Pan-NEN. Tumor and adjacent normal tissues were collected from 56 patients with Pan-NEN. Immunohistochemical analysis was conducted on tumor tissues using a panel of monoclonal antibodies targeting key immune markers. The expression levels of these markers were quantitatively assessed and correlated with clinicopathological features and overall survival. Low expression of CD3, CD8, CD4, CD68, CD163, Foxp3, CD56, CD69, GZMB, HLA-1, HLA-II, PD-1, and PD-L1 were observed in the majority of Pan-NEN patient samples. PD-1 expression was positively correlated with CD4 and Foxp3 expression, while PD-L1 expression was positively correlated with CD68, CD163, and Foxp3 expression; HLA-II expression was positively correlated with GZMB expression. Infiltration of lymphocytes (CD3 + or CD8+) and macrophages (CD68 + or CD163+) and expression of PD-1/PD-L1 were more pronounced in poorly differentiated neuroendocrine carcinoma (Pan-NEC) compared to well-differentiated neuroendocrine tumors (Pan-NET), while CD68 and PD-L1 correlated with advanced disease stage. Conversely, HLA-I antigen expression was commonly downregulated in Pan-NEC. Univariate Cox proportional hazard analysis demonstrated that tumor grade, stage; CD4+, CD68+, and CD163 + cell count; and expression of PD-1 and PD-L1 were significantly associated with poor survival outcomes, while the positive expression of HLA-I was correlated with a more favorable survival prognosis. Furthermore, multivariate Cox proportional hazard analyses revealed that tumor grade, stage, and PD-1 expression are independent prognostic factors. The immunological landscape of Pan-NEN offers potential prognostic value and therapeutic targets. The findings suggest that immunotherapy, particularly targeting the PD-1/PD-L1 pathway, may serve as a promising strategy for the treatment of Pan-NEN, especially for Pan-NEC patients.

TBK1 is involved in M-CSF-induced macrophage polarization through mediating the IRF5/IRF4 axis.

TANK binding kinase 1 (TBK1) is an important kinase that is involved in innate immunity and tumor development. Macrophage colony-stimulating factor (M-CSF) regulates the differentiation and function of macrophages towards the immunosuppressive M2 phenotype in the glioblastoma multiforme microenvironment. The role of TBK1 in macrophages, especially in regulating macrophage polarization in response to M-CSF stimulation, remains unclear. Here, we found high TBK1 expression in human glioma-infiltrating myeloid cells and that phosphorylated TBK1 was highly expressed in M-CSF-stimulated macrophages but not in granulocyte-macrophage CSF-induced macrophages (granulocyte-macrophage-CSF is involved in the polarization of M1 macrophages). Conditional deletion of TBK1 in myeloid cells induced M-CSF-stimulated bone marrow-derived macrophages to exhibit a proinflammatory M1-like phenotype with increased protein expression of CD86, interleukin-1β and tumor necrosis factor-α, as well as decreased expression of arginase 1. Mechanistically, TBK1 deletion or inhibition by amlexanox or GSK8612 reduced the expression of the transcription factor interferon-regulatory factor (IRF)4 and increased the level of IRF5 activation in macrophages stimulated with M-CSF, leading to an M1-like profile with highly proinflammatory factors. IRF5 deletion reversed the effect of TBK1 inhibition on M-CSF-mediated macrophage polarization. Our findings suggest that TBK1 contributes to the regulation of macrophage polarization in response to M-CSF stimulation partly through the IRF5/IRF4 axis.

Abstract A031: Unhelpful CD4 help: Removal of conventional CD4+ T cells promotes priming of tumor antigen-specific CD8 T cells in the context of CD4-depletion therapy

Abstract Preclinical and clinical studies have used antibodies to deplete CD4-expressing cells to promote anti-tumor immunity. Specifically, a monoclonal anti-CD4 antibody (anti-CD4) has been employed to remove FOXP3+ CD4+ regulatory T cells (Tregs), which are known to impede anti-tumor immunity. Our previous studies demonstrated that administering anti-CD4 during B16 melanoma tumor growth in mice leads to the generation of tumor Ag-specific CD8 T cells that disseminate and form memory following surgical tumor excision. However, the importance of co-depleting other CD4-expressing cell compartments for anti-CD4 treatment efficacy are unknown. We utilized flow cytometry and single-cell RNA sequencing (scRNAseq) to evaluate the primary response of tumor Ag-specific CD8 T cells (pmel) in B16 melanoma tumor bearing mice treated with anti-CD4. Responses were compared to those induced by anti-PD1 and anti-CTLA4 dual immune checkpoint blockade (ICB). To determine the importance of homeostatic space in priming, homeostatic expansion and priming were decoupled, and neutralizing antibodies were administered. Treg-depleted (Foxp3-DTR) mice were used for comparison, and Batf3-/- mice and IL-2R blocking antibodies were used to determine requirements for CD8 T cell priming. Finally, scRNAseq was conducted on CD4 T cells from human melanoma tumors previously treated with ICB to characterize transcriptional properties of intratumoral CD4 T cells. Compared to ICB, anti-CD4 treatment elicited a more robust, disseminated, and persistent primary tumor Ag-specific CD8 T cell response. ScRNAseq revealed that anti-CD4 treatment induced more stem-like (TCF1+) memory precursor cells, whereas ICB induced more differentiated effector (Gzmb+) cells. Removal of homeostatic space or blockade of IL-7R and IL-15 during priming did not diminish pmel responses in anti-CD4 treated mice, indicating that homeostatic space was not required. Importantly, pmel cells were shown to produce their own IL-2, and pmel priming was significantly lower after IL-2 receptor blockade, suggesting dependence on autocrine IL-2 signals. Using DT-treated FOXP3-DTR mice, we found that targeted Treg depletion was insufficient for the pmel priming that disseminated and formed memory, indicating that total CD4 T cell depletion was required for this systemic response. Depletion of total CD4 T cells uniquely increased cDC1 proportions in tumor-draining LNs as well as their expression of CD86. However, treatment of tumor-bearing RAG-/- mice with anti-CD4 confirmed that depletion of CD4-expressing APC compartments does not contribute to anti-CD4 treatment efficacy. ScRNAseq of CD4 T cells from human melanoma tumors showed dominance of Tr1-like cells and other subsets without transcriptional evidence of helper differentiation, despite prior ICB. In mice, combination of anti-CD4 with dual ICB restored the systemic response of tumor-specific CD8 T cells. This study underscores the importance of eliminating conventional CD4 T cells in tumor-bearing hosts to elicit systemic primary and memory CD8 T cell responses. Citation Format: Christo P. C. Dragnev, Delaney E. Ramirez, Tyler G. Searles, Nathaniel Spicer, TIffany Chen, J. Louise Lines, Aaron R. Hawkes, Wilson L. Davis III, Asmaa Mohamed, Keisuke Shirai, Joesph D. Phillips, Pamela C. Rosato, Yina H. Huang, Mary Jo Turk. Unhelpful CD4 help: Removal of conventional CD4+ T cells promotes priming of tumor antigen-specific CD8 T cells in the context of CD4-depletion therapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor Immunology and Immunotherapy; 2024 Oct 18-21; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2024;12(10 Suppl):Abstract nr A031.