Intralymphatic GAD-alum Injection Modulates B Cell Response and Induces Follicular Helper T Cells and PD-1+ CD8+ T Cells in Patients With Recent-Onset Type 1 Diabetes

Antigen-specific immunotherapy is an appealing strategy to preserve beta-cell function in type 1 diabetes, although the approach has yet to meet its therapeutic endpoint. Direct administration of autoantigen into lymph nodes has emerged as an alternative administration route that can improve the efficacy of the treatment. In the first open-label clinical trial in humans, injection of aluminum-formulated glutamic acid decarboxylase (GAD-alum) into an inguinal lymph node led to the promising preservation of C-peptide in patients with recent-onset type 1 diabetes. The treatment induced a distinct immunomodulatory effect, but the response at the cell level has not been fully characterized. Here we used mass cytometry to profile the immune landscape in peripheral blood mononuclear cells from 12 participants of the study before and after 15 months of treatment. The immunomodulatory effect of the therapy included reduction of naïve and unswitched memory B cells, increase in follicular helper T cells and expansion of PD-1+ CD69+ cells in both CD8+ and double negative T cells. In vitro stimulation with GAD65 only affected effector CD8+ T cells in samples collected before the treatment. However, the recall response to antigen after 15 months included induction of CXCR3+ and CD11c+Tbet+ B cells, PD-1+ follicular helper T cells and exhausted-like CD8+ T cells. This study provides a deeper insight into the immunological changes associated with GAD-alum administration directly into the lymph nodes.

Perspectives Concerning Various Symptoms of SARS-CoV-2 Detected Individuals

After exposure to SARS-CoV-2, varying symptoms of COVID-19 ranging from asymptomatic symptoms to morbidity and mortality have been exhibited in each individual. SARS-CoV-2 requires various cellular molecules for penetration into a target host cell. Angiotensin-converting enzyme2 (ACE2) acts as the viral receptor molecule. After attachment, SARS-CoV-2 also requires the transmembrane protease serine-2 (TMPRSS-2) and furin molecules, which serve as co-receptors for penetration into the target cell and for subsequent replication. In the meantime, a major histocompatibility complex (MHC) is required for the induction of adaptive immune cells, especially cytotoxic T cells and helper T cells, to clear the virally infected cells. This perspective review article proposes different aspects to explain the varying symptoms of the individuals who have been exposed to SARS-CoV-2, which relates to the polymorphisms of these involved molecules.

The Role of Helper T Cells in Psoriasis

Psoriasis is a complex, chronic relapsing and inflammatory skin disorder with a prevalence of approximately 2% in the general population worldwide. Psoriasis can be triggered by infections, physical injury and certain drugs. The most common type of psoriasis is psoriasis vulgaris, which primarily features dry, well-demarcated, raised red lesions with adherent silvery scales on the skin and joints. Over the past few decades, scientific research has helped us reveal that innate and adaptive immune cells contribute to the chronic inflammatory pathological process of psoriasis. In particular, dysfunctional helper T cells (Th1, Th17, Th22, and Treg cells) are indispensable factors in psoriasis development. When stimulated by certain triggers, antigen-presenting cells (APCs) can release pro-inflammatory factors (IL-23, IFN-α and IL-12), which further activate naive T cells and polarize them into distinct helper T cell subsets that produce numerous cytokines, such as TNF, IFN-γ, IL-17 and IL-22, which act on keratinocytes to amplify psoriatic inflammation. In this review, we describe the function of helper T cells in psoriasis and summarize currently targeted anti-psoriatic therapies.

Increased frequency of CD4+ and CD8+ follicular helper T cells in human lymph node biopsies during the earliest stages of rheumatoid arthritis

Objectives: Follicular helper T cells (Tfh cells) provide key B cell help, and are essential in germinal center (GC) formation and (auto) antibody generation. To gain more insight into their role during the earliest phase of rheumatoid arthritis (RA) we analyzed their frequencies, phenotype and cytokine profile in peripheral blood and lymphoid tissues. Methods: Using flow cytometry, we studied the frequency of Tfh and B cells in peripheral blood and lymph node (LN) needle biopsies. Three donor groups were included and compared: healthy controls (HCs), autoantibody positive individuals at risk for developing RA (RA-risk individuals), and early RA patients. Ex vivo stimulation of lymphocytes with PMA/ionomycin was performed to assess cytokine secretion by Tfh cells. Results: In blood, the frequency of circular Tfh cells (cTfh) did not differ between study groups. In lymphoid tissue, the frequency of Tfh cells correlated strongly with the frequency of CD19+ B cells. Compared to healthy controls, LN samples of RA patients and RA-risk individuals showed more CD19+ B cells and more CD4+CXCR5+ and CD8+CXCR5+ Tfh cells. These Tfh cells from LNs expressed less IL-21 upon ex vivo stimulation. Conclusion: LN tissue of early RA patients as well as part of RA-risk individuals exhibit increased frequencies of Tfh cells correlating with increased numbers of B cells. Interestingly, IL-21 production is already aberrant in the very early at risk phase of the disease. This suggests that Tfh cells may present a novel rationale for therapeutic targeting during the preclinical stage of the disease to prevent further disease progression.

High Siglec15 Expression in Triple Negative Breast Cancer Predicts Poor Prognosis

Introduction: Normalization cancer immunotherapy is a new strategy to treat breast cancer. Sialic acid binding Ig-like lectin 15 (Siglec-15) is a new potential target for normalization cancer immunotherapy. In this study, we evaluated the role of Siglec15 in breast cancer and investigated the influence of Siglec15 on the microenvironment of infiltrating immune cells in the cancer.Methods: We performed immunhistochemical staining to analyze Siglet-15 expression in primary invasive breast cancer tissue microarrays. The tissue specimens were from 90 patients. Furthermore, The relationship between Siglec15 and clinicopathological features was analyzed with logistic regression and the Wilcoxon signed-rank test. The association between clinical characteristics and overall survival in the Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) patients was assessed. Results: Immunhistochemical staining of tissue microarrays showed that Siglet-15 had higher expression in breast cancer tissues than those in adject normal tissues. Breast cancer tissues had higher Siglec15 expression than normal tissues. Kaplan-Meier survival analysis suggested that triple negative breast cancer with high Siglec15 expression had poorer survival than those with lower Siglec15 expression (p=0.042). Furthermore, high Siglec15 expression group had low activated dendritic cells, follicular helper T cells, and M1 macrophages. Conclusions: Siglet-15 had high expression in breast cancer tissues. High Siglec15 expression is associated with low activated dendritic cells, follicular helper T cells, and M1 macrophages proportions in breast cancer tissue, and predicts poor prognosis in triple negative breast cancer. Siglec15 expression may be a potential prognostic molecular marker of poor survival in breast cancer.

Determine the Effect of Immunosuppressant on follicular regulatory T-cells in kidney transplant patients

Background: Over the last few years, there are two major problems identified during organ transplantation such as surgical restrictions and transplant rejections. Few of these obstacles have been partially removed such as the use of immunosuppressant improved it consistently while decreasing graft rejection up to 12.2%. Methods: This study was conducted from 2019-2021. In all patients renal function was examined through glomerular filtration rate. Induction therapy was given to all the transplant recipients. Induction therapy with basiliximab 20mg intravenously on 0 and 4 days. After transplantation tacrolimus and MMF was given with varied concentration dose. Acute rejections were found in patients who had no biopsy or biopsy-proven rejection. In the end, clinical pathologists had analyzed all biopsies again and recipients who were experienced the vascular Banff grade 2 and tubule interstitial rejection. Results: Immunosuppressant tacrolimus treated patients were 71(67.61%) and mycophenolate mofetil used in 34(32.38%). Total 39(37.14%) rejections were received and 66(62.85%) acceptance was recorded. Two types of rejection were highlighted namely cell-mediated rejection 25(23.80%) and 14(13.33%) chronic antibody-mediated rejection. The effect of tacrolimus on follicular helper T cells and follicular regulatory T cells shows the clear difference between the kidney transplant and healthy control cells. Reduction in numbers of follicular regulatory T cells was measured in patients. Conclusion: eventually we find tacrolimus significantly affects the number of follicular regulatory T-cells and follicular helper T cells. Alemtuzumab substantially lowers the follicular regulatory T-cells. Mycophenolate mofetil showed non-significant on T-cells. Keywords: kidney transplant, follicular regulatory T-cells, follicular helper T-cells.

Spatial Profiles of Intratumoral PD-1+ Helper T Cells Predict Prognosis in Head and Neck Squamous Cell Carcinoma

BackgroundFunctional interactions between immune cells and neoplastic cells in the tumor immune microenvironment have been actively pursued for both biomarker discovery for patient stratification, as well as therapeutic anti-cancer targets to improve clinical outcomes. Although accumulating evidence indicates that intratumoral infiltration of immune cells has prognostic significance, limited information is available on the spatial infiltration patterns of immune cells within intratumoral regions. This study aimed to understand the intratumoral heterogeneity and spatial distribution of immune cell infiltrates associated with cell phenotypes and prognosis in head and neck squamous cell carcinoma (HNSCC).MethodsA total of 88 specimens of oropharyngeal squamous cell carcinoma, categorized into discovery (n = 38) and validation cohorts (n = 51), were analyzed for immune contexture by multiplexed immunohistochemistry (IHC) and image cytometry-based quantification. Tissue segmentation was performed according to a mathematical morphological approach using neoplastic cell IHC images to dissect intratumoral regions into tumor cell nests versus intratumoral stroma.ResultsTissue segmentation revealed heterogeneity in intratumoral T cells, varying from tumor cell nest-polarized to intratumoral stroma-polarized distributions. Leukocyte composition analysis revealed higher ratios of TH1/TH2 in tumor cell nests with higher percentages of helper T cells, B cells, and CD66b+ granulocytes within intratumoral stroma. A discovery and validation approach revealed a high density of programmed death receptor-1 (PD-1)+ helper T cells in tumor cell nests as a negative prognostic factor for short overall survival. CD163+ tumor-associated macrophages (TAM) provided the strongest correlation with PD-1+ helper T cells, and cases with a high density of PD-1+ helper T cells and CD163+ TAM had a significantly shorter overall survival than other cases.ConclusionThis study reveals the significance of analyzing intratumoral cell nests and reports that an immune microenvironment with a high density of PD-1+ helper T cells in tumoral cell nests is a poor prognostic factor for HNSCC.

Tnfaip6 Secreted by Bone Marrow–Derived Mesenchymal Stem Cells Attenuates TNBS-Induced Colitis by Modulating Follicular Helper T Cells and Follicular Regulatory T Cells Balance in Mice

Objective: To investigate the immunological mechanism of bone marrow–derived mesenchymal stem cells (BM-MSCs) in inflammatory bowel disease (IBD).Methods: Mice with 2,4,6-trinitrobenzene sulfonic acid (TNBS)–induced colitis were intraperitoneally injected with phosphate-buffered saline, BM-MSCs, BM-MSCs with tumor necrosis factor–induced protein 6 (Tnfaip6) knockdown mediated by RNA interference recombinant adenovirus, and BM-MSCs–infected with control adenovirus or recombinant mouse Tnfaip6. The disease activity index, weight loss, and histological scores were recorded. Serum levels of Tnfaip6 and pro- and anti-inflammatory cytokines, including interleukin (IL)-21, tumor necrosis factor-alpha (TNF-α), IL-10 were measured by enzyme-linked immunosorbent assay. The relative expression levels of these cytokines, B-cell lymphoma 6 (BCL-6) and fork-like transcription factor p3 (Foxp3) in the colon were determined by real-time quantitative PCR (RT-qPCR). BCL-6 and Foxp3 are the master regulators of follicular helper T cells (Tfh) and follicular regulatory T cells (Tfr), respectively. The infiltration of Tfh and Tfr in mesenteric lymph nodes (MLNs) and spleens was analyzed by flow cytometry.Results: Compared to the normal control group, the expression levels of BCL-6 and IL-21 in the colon, Tfh infiltration, and ratios of Tfh/Tfr in the MLNs and spleen, and the serum concentrations of IL-21 and TNF-α increased significantly in the colitis model group (p < 0.05). Intraperitoneal injection of BM-MSCs or Tnfaip6 ameliorated weight loss and clinical and histological severity of colitis, downregulated the expression of BCL-6, IL-21, and TNF-α, upregulated the expression of Foxp3, IL-10, and Tnfaip6 (p < 0.05), increased Tfr and reduced the infiltration of Tfh in the MLNs and spleen, and downregulated the Tfh/Tfr ratio (p < 0.05). On the other hand, BM-MSCs lost the therapeutic effect and immune regulatory functions on Tfh and Tfr after Tnfaip6 knockdown.Conclusion: Tfh increase in the inflamed colon, Tfh decrease and Tfr increase during the colitis remission phase, and the imbalance of the Tfh/Tfr ratio is closely related to the progression of IBD. Tnfaip6 secreted by BM-MSCs alleviates IBD by inhibiting Tfh differentiation, promoting Tfr differentiation, and improving the imbalance of Tfh/Tfr in mice.