Search Results (39)

Kidney diseases in patients with SLE include glomerulonephritis (GN), tubulointerstitial nephritis (TIN) and vasculitis alone or in combination. Immune complex (IC) deposition with complement activation in renal glomeruli causes lupus GN. However, IC deposition can also occur in the tubular basement membrane, renal interstitium, peritubular capillaries and arteries/arterioles to elicit inflammatory responses. TIN is usually associated with more severe GN with inflammation induced by IC. Immunopathologically, the aberrant presentation of T cell subpopulations, T_h1, T_h2, T_h9, T_h17, Treg and follicular T helper cells (T_fh), is closely implicated in TIN in SLE. In addition, M₁/M₂ macrophages and more specific dendritic cells (DCs) contribute to the inflammatory reactions of SLE-TIN. TIN may also present alone (isolated TIN) in apparently normal glomeruli or class I GN. It is intriguing that lupus nephritis constitutes two different pathological predilections, i.e., GN and tubulointerstitial inflammation. Alternatively, these two types may represent a continuous spectrum of inflammatory renal damages. In the present review, we will discuss in detail the pathology/immunopathogenesis, likely specific biomarkers/predictors and novel therapeutic designs for SLE-tubulointerstitial inflammation. In addition, we also raise several plausible investigation methods in SLE-tubulointerstitial inflammation that may help further elucidate this setting of perplexing renal diseases with rheumatic characteristics. Full article

Homeostasis must be maintained for the healthy living of an organism. In addition to physiological and anatomical homeostasis, the maintenance of the immune system, called immune homeostasis or immunohomeostasis, is critical for overall well-being and general homeostasis. CD8⁺ cytotoxic T cells/lymphocytes (CTLs) are crucial components of the adaptive immune systems of all vertebrates with a thymus. Hence, the thymus is an essential primary lymphoid organ (PLO) for developing T cell-mediated immunity (TCMI) that comprises CD4⁺ helper T cells (Th) cells and their subtypes, such as Th0 (naïve helper T cells), Th1 (pro-inflammatory Th cells that secrete IFN-γ), Th2 (secrete type 2 cytokines, such as IL-4, IL-5, IL-6, IL-10, and IL-13), Th9 (secrete IL-9), Th17 (secrete IL-17), Th22 (secrete IL-22), follicular Th cells (T_fhs, secrete IL-21), regulatory T cells (T_regs), and CD8⁺CTLs. The current article explores the critical role of CD8⁺CTLs in the maintenance of immune homeostasis. The role of the thymus (PLO) in generating and regulating CD8⁺CTLs, as well as mobilizing them to distant lymph nodes (LNs) and the spleen, which are referred to as secondary lymphoid organs (SLOs) and target organs, is discussed in section two of the article. The subsequent third section discusses the role of CD8⁺CTLs’ cytotoxic and immunoregulatory action to maintain immune homeostasis during infection and other inflammatory conditions. Moreover, they mask themselves to different cell types, like Th cells, such as Tc2s, Tc9s, Tc17s, and Tc22s, to maintain immune homeostasis. CD8⁺CTLs also behave as T_regs to exert their immunoregulatory functions. In addition to conventional CD8⁺CTLs, granzyme K (GzmK)⁺CD8⁺CTLs and CD4⁺CTLs with their cytotoxic action to maintain immune homeostasis have also been discussed. The next section discusses cell–cell (APC–CD8⁺CTL) interactions that not only increase the cytotoxic functions of CD8⁺CTLs but also program APCs to support their cytotoxic functions. These CD8⁺CTLs secrete different cytokines (IFN-γ and IL-10) and cytotoxic molecules (perforin and Gzms), which exert immunoregulatory actions to maintain immune homeostasis. The article concludes with a future perspective and a conclusion section, highlighting the critical need to understand CD8⁺CTLs’ cytotoxic and immunoregulatory functions in maintaining immune homeostasis across various diseases, including those with newly identified roles for CD8⁺CTLs. Full article

Introduction: In mouse models of chronic lymphocytic leukemia (CLL), an effective anti-leukemia immune response was obtained by depleting a specific regulatory T-cell (Treg) subset. While STAT5 signaling could alter the homeostasis of naïve (nTreg) and activated (aTreg) subsets, which are capable of suppressing also CLL patients’ responses to microbial antigens, perturbed STAT3 signaling could drive CXCR5 expression in circulating T-follicular regulatory cells (Tfr) and their entry into the lymph node/tumor microenvironment. Materials and Methods: By using phospho-specific flow cytometry, we monitored STAT signaling/phosphorylation (pSTAT), in vitro responses to Sars-Cov2-antigen-specific stimulation, and circulating Treg subsets in relation to Binet stage and total tumor mass/tumor distribution (TTM/TD) scoring in 62 patients with CLL. Results: The percentage of CXCR5⁺ Treg significantly increased in patients with Binet stage B disease, and Tfr-like subsets were associated with higher TTM and lower TD. The pSTAT3 levels in CD4⁺ T-cells were only significantly increased in patients undergoing therapy. Lower nTreg percentages correlated with increased disease duration, and an increased aTreg/nTreg ratio correlated with SARS-CoV-2-antigen-induced STAT5 signaling responses. Conclusions: The results show increased amounts of circulating CXCR5⁺ Tfr-like subsets in patients with extensive lymph node involvement and augmented STAT3 signaling in patients on therapy. While STAT5 responses may drive nTreg differentiation into aTreg, nTreg decline is associated with increased disease duration. Full article

Background: Breast cancer is a heterogeneous malignant disease with a varying prognosis and is classified into four molecular subtypes. It remains one of the most prevalent cancers globally, with the tumor microenvironment playing a critical role in disease progression and patient outcomes. Methods: This study evaluated tumor samples from 40 female patients with luminal A and B breast cancer, utilizing flow cytometry to phenotypically characterize the immune cells and tumor cells present within the tumor tissue. Results: The luminal B-like tumor samples exhibited increased infiltration of CD4⁺ cells, regulatory T cells (Tregs), and Th17 cells and decreased levels of NK cells, γδ T cells, Th1 cells, and follicular T cells, which is indicative of a more immunosuppressive tumor microenvironment. Conclusions: These findings suggest that luminal B-like tumors have a microenvironment that is less supportive of effective anti-tumor immune responses compared to luminal A tumors. This study enhances the understanding of the immunological differences between luminal subtypes of breast cancer and identifies potential new therapeutic targets and biomarkers that could drive advancements in precision medicine for breast cancer management. Full article

IgG4-RD is a multisystem fibroinflammatory disease characterized by the infiltration of tissues by IgG4 plasma cells. Combined skin and biliary tract involvement in IgG4-RD has not been described. We present perhaps the most comprehensive analysis of lymphocyte subsets in the first case of IgG4-related generalized skin rash and first case of combined skin and biliary tract manifestations. A 55-year-old male presented with painful jaundice and generalized macular pigmented pruritic eruptions, and CT abdomen revealed biliary obstruction. Ampulla and skin biopsies were subjected to histology and immunostaining. Naïve, central memory (T_CM), effector memory (T_EM), terminally differentiated effector memory (T_EMRA) subsets of CD4+ and CD8+ T cells, T follicular helper subsets, naïve, transitional, marginal zone (MZ), germinal center (GC), IgM memory, and class-switched memory (CSM) B cells, and T follicular regulatory, regulatory B cells, CD4 Treg, and CD8 Treg were analyzed. Serum IgG4 was elevated at 448 mg/dL. Ampula biopsy showed lamina propria fibrosis and increased IgG4-positive plasma cells. Skin punch biopsy showed lymphoplasmacytic infiltrates with a 67% ratio of IgG4+:IgG+ plasma cells. CD4+T_N and CD4+T_CM decreased, whereas CD4+T_EM increased. Naïve B cells increased; transitional, MZ, CSM, GC B cells, and plasmablasts decreased compared to control. CD4 Treg increased, whereas CD8 Treg and Breg decreased. In conclusion, IgG-RD may present with combined biliary tract and generalized dermatological manifestations. Changes in regulatory lymphocytes suggest their role in the pathogenesis of IgG4-RD. Full article

Human immunodeficiency virus (HIV) infection remains an important global public health problem. About 40 million people are infected with HIV, and this infection caused about 630,000 deaths in 2022. The hallmark of HIV infection is the depletion of CD4+ T helper lymphocytes (Th cells). There are at least seven different Th subtypes, and not all are the main targets of HIV. Moreover, the effect of the virus in a specific subtype can be completely different from that of the others. Although the most compromised Th subtype in HIV infection is Th17, HIV can induce important dysregulations in other subtypes, such as follicular Th (Tfh) cells and regulatory Th cells (Treg cells or Tregs). Several studies have shown that HIV can induce an increase in the immunosuppressive activity of Tregs without causing a significant reduction in their numbers, at least in the early phase of infection. The increased activity of this Th subtype seems to play an important role in determining the immunodeficiency status of HIV-infected patients, and Tregs may represent a new target for innovative anti-HIV therapies, including the so-called “Kick and Kill” therapeutic method whose goal is the complete elimination of the virus and the healing of HIV infection. In this review, we report the most important findings on the effects of HIV on different CD4+ T cell subtypes, the molecular mechanisms by which the virus impairs the functions of these cells, and the implications for new anti-HIV therapeutic strategies. Full article

Combination therapy of nivolumab and ipilimumab (NIVO + IPI) for metastatic renal cell carcinoma (mRCC) has shown efficacy, but approximately 20% of patients experience disease progression in the early stages of treatment. No useful biomarkers have been reported to date. Therefore, it is desirable to identify biomarkers to predict treatment responses in advance. We examined the tumor microenvironment (TME)-related gene expression in mRCC patients treated with NIVO + IPI, between the response and non-response groups, using tumor tissues, before administering NIVO + IPI. In TME-related genes, TNFSF9 expression was identified as a candidate for the predictive biomarker. Its expression discriminated between the response and non-response groups with 88.89% sensitivity and 87.50% specificity (AUC = 0.9444). We further analyzed the roles of TNFSF9 in TME using bioinformatics from The Cancer Genome Atlas (TCGA) cohort. An adaptive immune response was activated in the TNFSF9-high-expression tumors. Indeed, T follicular helper cells, plasma B cells, and tumor-infiltrating CD8⁺ T cells were increased in the tumors, which indicates the promotion of humoral immunity due to enhanced T-B interactions. However, as the number of regulatory T cells (Treg) increased in the tumors, the percentage of dysfunctional T cells also increased. This suggests that not only PD-1 but also CTLA-4 inhibition may have suppressed Treg activation and improved the therapeutic effect in the TNFSF9 high-expression tumors. Therefore, TNFSF9 may predict the therapeutic efficacy of NIVO + IPI for mRCC and allow more appropriate patient selection. Full article

Since the start of the COVID-19 pandemic, in a short span of 3 years, vaccination against SARS-CoV-2 has resulted in the end of the pandemic. Patients with inborn errors of immunity (IEI) are at an increased risk for SARS-CoV-2 infection; however, serious illnesses and mortality, especially in primary antibody deficiencies (PADs), have been lower than expected and lower than other high-risk groups. This suggests that PAD patients may mount a reasonable effective response to the SARS-CoV-2 vaccine. Several studies have been published regarding antibody responses, with contradictory reports. The current study is, perhaps, the most comprehensive study of phenotypically defined various lymphocyte populations in PAD patients following the SARS-CoV-2 vaccine. In this study, we examined, following two vaccinations and, in a few cases, prior to and following the 1st and 2nd vaccinations, subsets of CD4 and CD8 T cells (Naïve, T_CM, T_EM, T_EMRA), T follicular helper cells (T_FH1, T_FH2, T_FH17, T_FH1/17), B cells (naïve, transitional, marginal zone, germinal center, IgM memory, switched memory, plasmablasts, CD21^low), regulatory lymphocytes (CD4Treg, CD8Treg, T_FR, Breg), and SARS-CoV-2-specific activation of CD4 T cells and CD8 T cells (CD69, CD137), SARS-CoV-2 tetramer-positive CD8 T cells, and CD8 CTL. Our data show significant alterations in various B cell subsets including Breg, whereas only a few subsets of various T cells revealed alterations. These data suggest that large proportions of PAD patients may mount significant responses to the vaccine. Full article

Endomucin (EMCN) contributes to both cell adhesion and signaling processes, thereby participating in the modulation of immune responses within the vasculature. In this study, we uncover how EMCN modulates the tumor immune microenvironment in clear-cell renal cell carcinoma (ccRCC). The Cancer Genome Atlas (TCGA) was used to obtain clinicopathological and expression data on KIRC. The prognostic significance of EMCN expression in ccRCC was assessed through univariate analysis. DNMIVD was used to investigate the methylation status of EMCN in tumor and normal adjacent tissue (NAT). TCGExplorer was utilized to employ GSEA to identify pathways enriched by the high or low expression of EMCN. Hallmark Gene sets from MSigDB were utilized. The immune microenvironment was evaluated using the Tumor IMmune Estimation Resource (TIMER 2.0). High EMCN expression was associated with heightened overall survival and better survival (HR: 0.60, 95% CI: 0.52–0.68, p < 0.0001) in the TCGA ccRCC cohort. The promoter region of EMCN was hypermethylated in tumor tissue, in contrast to normal adjacent tissue, with an increased beta value of 0.13715 (p < 0.001) associated with decreased expression of EMCN in tumor tissue compared to NAT. The top three enriched GSEA terms when EMCN was highly expressed were hallmark_TGF_beta_signaling, KRAS_signalling_up, and Apical_junction. In contrast, when the expression of EMCN was low, E2F_targets, Oxidative_phosphorylation, and MYC_targets_v2 were the top terms. EMCN expression was positively correlated with resting memory CD4+T cells (ρ = 0.217, p = 2.68e⁻⁶), naïve B cells (ρ = 0.273, p = 2.43e⁻⁹), plasma B cells (ρ = 0.158, p = 6.73e⁻⁴), M1 macrophages (ρ = 0.167, p = 3.05e⁻⁴), Monocytes (ρ = 0.29, p = 2.17e⁻¹⁰), resting NK cells (ρ = 0.208, p = 6.39e⁻⁶), activated mast cells (ρ = 0.373, p = 1.05e⁻¹⁶), and M2 macrophages (ρ = 0.127, p = 6.45e⁻³). It correlated negatively with Tregs (ρ = −0.349, p = 1.23e⁻¹⁴), activated memory CD4+ T cells (ρ = −0.17, p = 2.42e⁻⁴), follicular helper T cells (ρ = −0.209, p = 6.20e⁻⁶), neutrophils (ρ = −0.101, p = 3.07e⁻²), M0 macrophages (ρ = −0.333, p = 2.15e⁻¹³), and memory B cells (ρ = −0.217, p = 2.53e⁻⁶). Full article

Sensitization to HLA can result in allograft loss for kidney transplantation (KT) patients. Therefore, it is required to develop an appropriate desensitization (DSZ) technique to remove HLA-donor-specific anti-HLA antibody (DSA) before KT. The aim of this research was to investigate whether combined use of the IL-6 receptor-blocking antibody, tocilizumab (TCZ), and bone-marrow-derived mesenchymal stem cells (BM-MSCs) could attenuate humoral immune responses in an allo-sensitized mouse model developed using HLA.A2 transgenic mice. Wild-type C57BL/6 mice were sensitized with skin allografts from C57BL/6-Tg (HLA-A2.1)1Enge/J mice and treated with TCZ, BM-MSC, or both TCZ and BM-MSC. We compared HLA.A2-specific IgG levels and subsets of T cells and B cells using flow cytometry among groups. HLA.A2-specific IgG level was decreased in all treated groups in comparison with that in the allo-sensitized control (Allo-CONT) group. Its decrease was the most significant in the TCZ + BM-MSC group. Regarding the B cell subset, combined use of TCZ and BM-MSC increased proportions of pre-pro B cells but decreased proportions of mature B cells in BM (p < 0.05 vs. control). In the spleen, an increase in transitional memory was observed with a significant decrease in marginal, follicular, and long-lived plasma B cells (p < 0.05 vs. control) in the TCZ + BM-MSC group. In T cell subsets, Th2 and Th17 cells were significantly decreased, but Treg cells were significantly increased in the TCZ+BM-MSC group compared to those in the Allo-CONT group in the spleen. Regarding RNA levels, IL-10 and Foxp3 showed increased expression, whereas IL-23 and IFN-γ showed decreased expression in the TCZ + BM-MSC group. In conclusion, combined use of TCZ and BM-MSC can inhibit B cell maturation and up-regulate Treg cells, finally resulting in the reduction of HLA.A2-specific IgG in a highly sensitized mouse model. This study suggests that the combined use of TCZ and BM-MSC can be proposed as a novel strategy in a desensitization protocol for highly sensitized patients. Full article

Glioblastoma is a highly aggressive cancer associated with a dismal prognosis, with a mere 5% of patients surviving beyond five years post diagnosis. Current therapeutic modalities encompass surgical intervention, radiotherapy, chemotherapy, and immune checkpoint inhibitors (ICBs). However, the efficacy of ICBs remains limited in glioblastoma patients, necessitating a proactive approach to anticipate treatment response and resistance. In this comprehensive study, we conducted a rigorous analysis involving two distinct glioblastoma patient cohorts subjected to PD-1 blockade treatments. Our investigation revealed that a significant portion (60%) of patients exhibit persistent disease progression despite ICB intervention. To elucidate the underpinnings of resistance, we characterized the immune profiles of glioblastoma patients with continued cancer progression following anti-PD1 therapy. These profiles revealed multifaceted defects, encompassing compromised macrophage, monocyte, and T follicular helper responses, impaired antigen presentation, aberrant regulatory T cell (Tregs) responses, and heightened expression of immunosuppressive molecules (TGFB, IL2RA, and CD276). Building upon these resistance profiles, we leveraged cutting-edge machine learning algorithms to develop predictive models and accompanying software. This innovative computational tool achieved remarkable success, accurately forecasting the progression status of 82.82% of the glioblastoma patients in our study following ICBs, based on their unique immune characteristics. In conclusion, our pioneering approach advocates for the personalization of immunotherapy in glioblastoma patients. By harnessing patient-specific attributes and computational predictions, we offer a promising avenue for the enhancement of clinical outcomes in the realm of immunotherapy. This paradigm shift towards tailored therapies underscores the potential to revolutionize the management of glioblastoma, opening new horizons for improved patient care. Full article

Peripheral T-cell lymphomas (PTCLs) are a group of diseases with a low incidence, high degree of heterogeneity, and a dismal prognosis in most cases. Because of the low incidence of these diseases, there have been few therapeutic novelties developed over time. Nevertheless, this fact is changing presently as epigenetic modifiers have been shown to be recurrently mutated in some types of PTCLs, especially in the cases of PTCLs not otherwise specified (PTCL-NOS), T follicular helper (TFH), and angioimmunoblastic T-cell lymphoma (AITL). These have brought about more insight into PTCL biology, especially in the case of PTCLs arising from TFH lymphocytes. From a biological perspective, it has been observed that ten-eleven translocators (TET2) mutated T lymphocytes tend to polarize to TFH, while Tregs lose their inhibitory properties. IDH2 R172 was shown to have inhibitory effects on TET2, mimicking the effects of TET2 mutations, as well as having effects on histone methylation. DNA methyltransferase 3A (DNMT3A) loss-of-function, although it was shown to have opposite effects to TET2 from an inflammatory perspective, was also shown to increase the number of T lymphocyte progenitors. Aside from bringing about more knowledge of PTCL biology, these mutations were shown to increase the sensitivity of PTCLs to certain epigenetic therapies, like hypomethylating agents (HMAs) and histone deacetylase inhibitors (HDACis). Thus, to answer the question from the title of this review: We found the Achilles heel, but only for one of the Achilles. Full article

Considering the large number of individuals who have already been infected and may have reinfection, the post-infection effects of COVID-19 are of great importance for clinical practice and predicting disease trends. However, our understanding of the potential long-term effects, particularly on immunity, after recovering from COVID-19 remains limited. The aim of this study was to investigate the abnormal immunological factors that contribute to the prolonged immunological effects of COVID-19. Two groups of patients were enrolled in the study, including 11 individuals with various autoimmune diseases (AIDs) and 16 patients diagnosed with systemic lupus erythematosus (SLE). Detailed clinical symptoms were closely monitored, and peripheral mononuclear cells were analyzed using flow cytometry. The clinical status was evaluated using the SLE Disease Activity Index (SLEDAI) and the Clinical Global Impressions (CGI) index. The proportions of follicular T helper cells (Tfh) exhibited significant increases in both cohorts (AID: p = 0.03; SLE: p = 0.0008). Conversely, the percentages of Foxp3⁺ and CD4⁺ regulatory T cells (Treg) were reduced in patients following COVID-19 infection (AID: p = 0.009, 0.05, resp.; SLE: p = 0.02, 0.0009, resp.). The percentages of Th2 and Th17 cells were significantly increased in SLE patients (p < 0.05). Exacerbated conditions were observed in SLE patients two months after infection (SLEDAI, p < 0.05). Our findings show that COVID-19 infection increases Tfh cells and decreases Treg cells in patients of AIDs, worsening pathogenetic immune status in post-recovery populations. Full article

A comprehensive framework has been established for understanding immunological pathways, which can be categorized into eradicated and tolerable immune responses. Toll-like receptors (TLRs) are associated with specific immune responses. TH1 immunity is related to TLR7, TLR8, and TLR9, while TH2 immunity is associated with TLR1, TLR2, and TLR6. TH22 immunity is linked to TLR2, TLR4, and TLR5, and THαβ (Tr1) immunity is related to TLR3, TLR7, and TLR9. The chemokine receptor CXCR5 is a marker of follicular helper T cells, and other chemokine receptors can also be classified within a framework based on host immunological pathways. On the basis of a literature review on chemokines and immunological pathways, the following associations were identified: CCR5 with TH1 responses, CCR1 with TH1-like responses, CCR4 (basophils) and CCR3 (eosinophils) with TH2 and TH9 responses, CCR10 with TH22 responses, CCR6 with TH17 responses, CXCR3 with THαβ responses, CCR8 with regulatory T cells (Treg), and CCR2 with TH3 responses. These findings contribute to the identification of biomarkers for immune cells and provide insights into host immunological pathways. Understanding the chemokine and Toll-like receptor system is crucial for comprehending the function of the innate immune system, as well as adaptive immune responses. Full article

COVID-19 infection not only profoundly impacts the detection of tuberculosis infection (Tbc) but also affects modality in tuberculosis patient immune response. It is important to determine immune response alterations in latent tuberculosis infection as well as in SARS-CoV-2-infected tuberculosis patients. Such changes may have underlying effects on the development and course of further tuberculosis. Here, we aimed to review the characteristics of immune response in TB patients or convalescent COVID-19 patients with latent TB infection (LTBI). Materials and Methods. We analyzed the features of immune response in tuberculosis and COVID-19 patients. For this, we analyzed publications released from December 2019 to March 2023; those which were published in accessible international databases (“Medline”, “PubMed”, “Scopus”) and with keywords such as “COVID-19”, “SARS-CoV-2”, “tuberculosis”, “pulmonary tuberculosis”, “latent tuberculosis infection”, “Treg”, “follicular Treg”, and “Treg subsets”, we considered. Results. Through our analysis, we found that tuberculosis patients who had been infected with COVID-19 previously and elevated Th1 and Th2 cell levels. High levels of Th1 and Th2 cells may serve as a positive marker, characterizing activated immune response during TB infection. COVID-19 or post-COVID-19 subjects showed decreased Th17 levels, indicating a lack of tuberculosis development. Moreover, the typical course of tuberculosis is associated with an increase in Treg level, but COVID-19 contributes to a hyperinflammatory response. Conclusion. According to the data obtained, the course of tuberculosis proceeds in a dissimilar way due to the distinct immune response, elicited by SARS-CoV-2. Importantly, the development of active tuberculosis with a severe course is associated with a decline in Treg levels. Both pathogens lead to disturbed immune responses, increasing the risk of developing severe TB. The insights and findings of this paper may be used to improve the future management of individuals with latent and active tuberculosis. Full article