Frequency Of Th Cells Research Articles

Antigen-specific T helper cells and cytokine profiles predict intensity and longevity of cellular and humoral responses to SARS-CoV-2 booster vaccination.

Pre-existent pools of coronavirus-specific or cross-reactive T cells were shown to shape the development of cellular and humoral immune responses after primary mRNA vaccination against SARS-CoV-2. However, the cellular determinants of responses to booster vaccination remain incompletely understood. Therefore, we phenotypically and functionally characterized spike antigen-specific T helper (Th) cells in healthy, immunocompetent individuals and correlated the results with cellular and humoral immune responses to BNT162b2 booster vaccination over a six-month period. Blood of 30 healthy healthcare workers was collected before, 1, 3, and 6 months after their 3rd BNT162b2 vaccination. Whole blood was stimulated with spike peptides and analyzed using flow cytometry, a 13-plex cytokine assay, and nCounter-based transcriptomics. Spike-specific IgG levels at 1 month after booster vaccination correlated with pre-existing CD154+CD69+IFN-γ+CD4+ effector memory cells as well as spike-induced IL-2 and IL-17A secretion. Early post-booster (1-month) spike IgG levels (r=0.49), spike-induced IL‑2 (r=0.58), and spike-induced IFN‑γ release (r=0.43) correlated moderately with their respective long-term (6-month) responses. Sustained robust IgG responses were significantly associated with S-specific (CD69+±CD154+±IFN-γ+) Th-cell frequencies before booster vaccination (p=0.038), especially double/triple-positive type-1 Th cells. Furthermore, spike IgG levels, spike-induced IL‑2 release, and spike-induced IFN‑γ release after 6 months were significantly associated with increased IL‑2 & IL‑4, IP‑10 & MCP1, and IFN‑γ & IP‑10 levels at 1 month post-booster, respectively. On the transcriptional level, induction of pathways associated with both T-cell proliferation and antigen presentation was indicative of sustained spike-induced cytokine release and spike-specific IgG production 6 months post-booster. Using support vector machine models, pre-booster spike-specific T-cell frequencies and early post-booster cytokine responses predicted sustained (6-month) responses with F1 scores of 0.80-1.00. In summary, spike-specific Th cells and T-cellular cytokine signatures present before BNT162b2 booster vaccination shape sustained adaptive cellular and humoral responses post-booster. Functional T-cell assays might facilitate early identification of potential non-responders.

Chronic Occupational Mold Exposure Drives Expansion of Aspergillus-Reactive Type 1 and Type 2 T-Helper Cell Responses.

Occupational mold exposure can lead to Aspergillus-associated allergic diseases including asthma and hypersensitivity pneumonitis. Elevated IL-17 levels or disbalanced T-helper (Th) cell expansion were previously linked to Aspergillus-associated allergic diseases, whereas alterations to the Th cell repertoire in healthy occupationally exposed subjects are scarcely studied. Therefore, we employed functional immunoassays to compare Th cell responses to A. fumigatus antigens in organic farmers, a cohort frequently exposed to environmental molds, and non-occupationally exposed controls. Organic farmers harbored significantly higher A. fumigatus-specific Th-cell frequencies than controls, with comparable expansion of Th1- and Th2-cell frequencies but only slightly elevated Th17-cell frequencies. Accordingly, Aspergillus antigen-induced Th1 and Th2 cytokine levels were strongly elevated, whereas induction of IL-17A was minimal. Additionally, increased levels of some innate immune cell-derived cytokines were found in samples from organic farmers. Antigen-induced cytokine release combined with Aspergillus-specific Th-cell frequencies resulted in high classification accuracy between organic farmers and controls. Aspf22, CatB, and CipC elicited the strongest differences in Th1 and Th2 responses between the two cohorts, suggesting these antigens as potential candidates for future bio-effect monitoring approaches. Overall, we found that occupationally exposed agricultural workers display a largely balanced co-expansion of Th1 and Th2 immunity with only minor changes in Th17 responses.

1902P - Dysregulation of helper T lymphocytes in esophageal squamous cell carcinoma (ESCC) patients is highly associated with aberrant production of miR-21

BackgroundDysregulation of helper T (Th) cell subsets has been contributed to the initiation and propagation of esophageal squamous cell carcinoma (ESCC). Different microRNAs (miRNAs) have been reported to control the development and functions of tumor-associated immune cells in ESCC. Here, we aimed to assess the IL-10, TGF-β, IFN-γ and IL-17a producing CD3+CD8- T cells in association whit miR-21, miR-29b, miR-106a and miR-155 expression in ESCC patients. MethodsA total of 34 ESCC patients including 12 newly diagnosed (ND) and 22 under-treatment (UT) cases and 34 age-matched healthy donors were enrolled. Flowcytometric characterization of stimulated T cells was performed by staining cells with fluorescent conjugated specific anti human CD3 and CD8 cell surface markers as well as IL-17a, IFN-γ, IL-10 and TGF-β intracytoplasmic cytokines. Circulating RNA was extracted from the plasma and qRT-PCR was used to evaluate the expression of miR-21 and miR-29b. TGF-β plasma levels were also assessed by ELISA. ResultsThe frequency of Th cells was significantly reduced in EC Patients. A significant increase in Tregs as well as Th17 cells population in both patient subgroups was observed. ND patients showed elevated level of Th1 cells and IL-10. However, the expression of IFN-γ was significantly decreased in Th cells. We also detected higher level of miR-21 in the ESCC patients which was significantly correlated with different subsets of Th cell. ConclusionsOur findings revealed that immune response related Th cells is highly impaired in ESCC patients and association between miR-21 and Th subsets could be correlated with the impairment of anti-tumor immunity and consequently ESCC pathogenesis which might be potentially used as an important target for immunotherapy. Legal entity responsible for the studyThe authors. FundingGolestan University of Medical Sciences; Semnan University of Medical Sciences. DisclosureAll authors have declared no conflicts of interest.

Dysregulation of helper T lymphocytes in esophageal squamous cell carcinoma (ESCC) patients is highly associated with aberrant production of miR-21.

Dysregulation of helper T (Th) cell subsets has been contributed to the initiation and propagation of esophageal squamous cell carcinoma (ESCC). Different microRNAs (miRNAs) have been reported to control the development and functions of tumor-associated immune cells in ESCC. Here, we aimed to assess the IL-10, TGF-β, IFN-γ, and IL-17a-producing CD3+CD8- T cells in association whit miR-21, miR-29b, miR-106a, and miR-155 expression in ESCC patients. A total of 34 ESCC patients including 12 newly diagnosed (ND) and 22 under-treatment (UT) cases and also34 age-matched healthy donors were enrolled. Flow cytometric characterization of stimulated T cells was performed by staining of the cells with fluorescent conjugated specific anti-human CD3 and CD8 cell surface markers as well as IL-17a, IFN-γ, IL-10, and TGF-β intracytoplasmic cytokines. Circulating RNA was extracted from the plasma, and qRT-PCR was used to evaluate the expression of microRNAs. TGF-β plasma levels were also assessed by ELISA. Results showed that the frequency of Th cells was significantly reduced in patients. A significant increase in Treg as well as Th17 cells population in both patient subgroups was observed. ND patients showed elevated level of Th1 cells and IL-10. However the mean expression of IFN-γ was significantly decreased in Th cells. We also detected higher level of miR-21 in the ESCC patients which was significantly correlated with different subsets of Th cells. Our findings revealed that immune response relatedto the Th cells is highly impaired in ESCC patients. Association between miR-21 and Th subsets could be correlated with the impairment of anti-tumor immunity and ESCC pathogenesis, which could be potentially used as an important target for immunotherapeutic approaches.

TH17 Cell Frequency in Peripheral Blood Is Elevated in Overweight Children without Chronic Inflammatory Diseases.

The prevalence of obesity has dramatically increased in children in the last few decades and is associated with chronic inflammatory diseases. Fat tissue produces IL-6 and TNF-α, which are stimuli for TH17 cell differentiation. These cells are characterized by expression of the transcription factor receptor-related orphan receptor C (RORC) and by IL-17A production. In murine models, obesity has been linked with elevated TH17 cell frequencies. The aim of this study was to explore whether being overweight was associated with an elevated frequency of circulating TH17 cells or elevated messenger RNA (mRNA)-levels of IL-17A and RORC in children without chronic inflammatory diseases. We studied peripheral blood samples from 15 overweight and 50 non-overweight children without a history of autoimmune diseases, asthma, atopic dermatitis or allergic rhinoconjunctivitis. TH17 cells were quantified in Ionomycin stimulated peripheral blood mononuclear cells by flow cytometry using intracellular IL-17A staining. RORC- and IL-17A expressions were measured by real-time PCR. We found significantly elevated TH cell frequencies in overweight children compared then on-overweight controls with 34.7 ± 1.5% of CD3+CD4+ cells versus 25.4 ± 2.4% (mean ± SEM, p = 0.0023), respectively. Moreover, TH cell frequencies correlated positively with body mass index (r = 0.42, p = 0.0005, respectively). The relative mRNA expression of RORC (p = 0.013) and IL-17A (p = 0.014) were upregulated in overweight compared to non-overweight children. Childhood obesity is an independent factor that is associated with an elevated frequency of circulating TH17 cells and higher expression of RORC- and IL-17A-mRNA after in vitro stimulation with Ionomycin. This might be due to the inflammatory activity of the fat tissue. Studies on TH17 immunity should not only be adjusted for acute and chronic inflammatory diseases but also for overweight.

Imbalanced expression of dysfunctional regulatory T cells and T-helper cells relates to immunopathogenesis in polyarteritis nodosa

Objectives: We investigated the characteristics of circulating T-helper (Th) cells and CD4+ regulatory T cells (Tregs) in polyarteritis nodosa (PAN).Methods: Peripheral blood samples were obtained from 14 patients with PAN. Nine patients having granulomatosis with polyangiitis (GPA) and 11 healthy individuals (HC) were enrolled as controls. Th cells and Tregs were analyzed by flow cytometry. Suppression assay of Tregs was simultaneously performed by evaluating the proliferation of conventional CD4+ T cells cocultured with Tregs.Results: The frequencies of Th cells were significantly higher in PAN than in HC. In comparison with GPA, the expression of Th1 cells was higher but that of Th17 cells was lower. Additionally, significant increase in Tregs was observed in PAN, which was correlated with the expression of Th1 cells; however, defects in suppressive ability and CTLA-4 expression were observed. The Th1-cell frequency was significantly decreased after immunosuppressive therapy in PAN; however, there were no improvements in other phenotypes or in Treg function.Conclusion: T-helper cell expansion and Treg dysfunction are thought to be associated with the pathogenesis of PAN. Th1 cells show a response to immunosuppressive therapy; however, the persistent immune abnormalities may interfere with complete recovery in patients with PAN.

Shifted T-cell polarisation after agricultural dust exposure in mice and men

RationaleA low prevalence of asthma and atopy has been shown in farmers and agricultural workers. However, in these workers, a higher prevalence of respiratory symptoms has been reported, in which...

Cross-protective immunity to porcine reproductive and respiratory syndrome virus by intranasal delivery of a live virus vaccine with a potent adjuvant

Porcine reproductive and respiratory syndrome (PRRS) is an immunosuppressive chronic respiratory viral disease of pigs that is responsible for major economic losses to the swine industry worldwide. The efficacy of parenteral administration of widely used modified live virus PRRS vaccine (PRRS-MLV) against genetically divergent PRRSV strains remains questionable. Therefore, we evaluated an alternate and proven mucosal immunization approach by intranasal delivery of PRRS-MLV (strain VR2332) with a potent adjuvant to elicit cross-protective immunity against a heterologous PRRSV (strain MN184). Mycobacterium tuberculosis whole cell lysate ( Mtb WCL) was chosen as a potent mucosal adjuvant due to its Th1 biased immune response to PRRS-MLV. Unvaccinated pigs challenged with MN184 had clinical PRRS with severe lung pathology; however, vaccinated (PRRS-MLV+ Mtb WCL) pigs challenged with MN184 were apparently healthy. There was a significant increase in the body weight gain in vaccinated compared to unvaccinated PRRSV challenged pigs. Vaccinated compared to unvaccinated, virus-challenged pigs had reduced lung pathology associated with enhanced PRRSV neutralizing antibody titers and reduced viremia. Immunologically, an increased frequency of Th cells, Th/memory cells, γδ T cells, dendritic cells, and activated Th cells and a reduced frequency of T-regulatory cells were detected at both mucosal and systemic sites. Further, reduced secretion of immunosuppressive cytokines (IL-10 and TGF-β) and upregulation of the Th1 cytokine IFN-γ in blood and lungs were detected in mucosally vaccinated, PRRSV-challenged pigs. In conclusion, intranasal immunization of pigs with PRRS-MLV administered with Mtb WCL generated effective cross-protective immunity against PRRSV.

T cell cytokine imbalance towards production of IFN‐γ and IL‐10 in NZB/W F1 lupus‐prone mice is associated with autoantibody levels and nephritis

Objective: The role of T cell‐derived cytokine production in lupus is poorly understood. We analysed the cytokine production of CD4+ T cells in the NZB/W F1 mouse strain, the mouse model probably most closely resembling human systemic lupus erythematosus (SLE), and assessed whether a possible shift in the cytokines expressed is associated with age or disease activity.Methods: We used intracellular cytokine staining and flow cytometry to determine the cytokine expression of splenic CD4+ T cells for interferon‐γ (IFN‐γ), tumour necrosis factor‐α (TNF‐α), interleukin‐4 (IL‐4) and IL‐10. NZB/W F1 mice at different ages spanning 5 to 36 weeks were analysed, healthy Balb/c×NZW F1 (CWF1) mice were used as controls. Serum anti‐double‐stranded DNA (anti‐dsDNA) antibody levels were determined by enzyme‐linked immunosorbent assay (ELISA), and proteinuria and plasma creatinine were estimated using commercial test kits.Results: The cytokine profile of CD4+ T cells was shifted towards T‐helper 1 (Th1) cells and the frequencies of Th cells expressing IFN‐γ+ correlated with age, anti‐dsDNA‐immunoglobulin G (IgG) titre and proteinuria. An increased percentage of IL‐10 producers correlated positively with anti‐dsDNA‐IgG and proteinuria, and a small gain in IL‐4 producers correlated with plasma creatinine. Neither the percentage of IL‐10 producers nor IL‐4 producers showed a significant correlation with age. There was no significant change observed in the frequency of TNF‐α T cells. The IFN‐γ/IL‐4 ratio demonstrated an increasing shift towards a Th1‐type response during disease development that was not present in healthy mouse strains.Conclusion: The association between the frequencies of T cells expressing IFN‐γ and IL‐10 and clinical findings suggests a key role for these cells in the pathogenesis of lupus.

Altered response of CD4+ T cell subsets to Plasmodium chabaudi chabaudi in B cell-deficient mice.

Mice depleted of B cells from birth by treatment with anti-mu antibodies can control but not clear an infection with the malaria parasite Plasmodium chabaudi chabaudi (AS). Splenic CD4+ T cells from these mice were unable to mount a significant Th2 response to the parasite in vitro as shown by much lower precursor frequencies of Th cells for antibody production and of IL-4-producing cells compared with the response of control-treated mice. CD4+ T cells of the anti-mu-treated mice which respond to antigens of P. chabaudi chabaudi maintained a Th1 phenotype throughout primary infection, in contrast to control mice in which a sequential appearance of Th1 and Th2 responses was observed. These data show that Th1 responses in anti-mu-treated mice are sufficient to control parasitemia but not to eliminate an infection. The data further suggest that depletion of B cells by treatment with anti-mu antibodies reduces the generation of the Th2 subset during a primary response to P. chabaudi chabaudi.

Interleukin 2/interleukin 4-independent T helper cell generation during an in vitro antigenic stimulation of mouse spleen cells in the presence of cyclosporin A.

Cyclosporin A (CsA), an immunosuppressive drug which completely suppresses the humoral response to thymus-dependent antigens, does not affect the generation of T helper (Th) cells during an in vitro stimulation of murine spleen cells with sheep red blood cells. The appearance of Th cells depends on time and their development can be prevented by X-ray irradiation performed at the onset of the culture and up to 3-4 days later; however, beyond this time, irradiation is ineffective, suggesting that cell proliferation is essentially completed by this time. The activity of Th cells generated in the presence of CsA is resistant to irradiation, indicating that the effector cells belong to a memory subset. Limiting dilution analysis has shown that the frequency of the Th cells recovered from 6-day sheep red blood cell-stimulated and CsA-treated cultures is of approximately 1.4 X 10(-3), representing an increment of about 500-fold compared to naive spleen cells. The increased frequency of Th cells and the sensitivity to irradiation of the generation of these cells demonstrate that Th cell precursors proliferate in the presence of CsA. Lymphokine genes transcription analysis confirms that the inhibition of interleukin (IL) 2/IL 4 gene expression is one target of CsA action. That the generation of Th memory cells can nevertheless take place strongly argues in favor of the existence of an IL 2/IL 4-independent pathway for murine T cell proliferation. Our finding that the transcription of the IL 7 gene is not inhibited by CsA raises the possibility for a role of this T cell growth factor in the generation of memory Th cells.

LYMPHOKINE PRODUCTION BY MLR-REACTIVE REACTION LYMPHOCYTES OBTAINED FROM NORMAL MICE AND MICE RENDERED TOLERANT OF CLASS II MHC ANTIGENS

A large proportion of mice rendered neonatally tolerant of class II MHC antigens respond to the tolerogen in vitro in an MLR, while simultaneously maintaining tolerance in vivo as evidenced by acceptance of a skin graft bearing the tolerated antigens. To determine whether this discrepancy between in vivo and in vitro tolerance is reflective of differences in the amount and/or type of lymphokines produced by tolerant lymphocytes, we have examined the ability of tolerogen-reactive lymphocytes to produce IL-2, IL-4/5, and IFN in vitro in an MLR. Our results demonstrate that when stimulated with the tolerogen, lymphocytes from both normal and tolerant responders produce IL-2 and interferon. However, in comparison to normal cells, 2 alterations in the tolerogen-specific responses of lymphocytes obtained from tolerant mice were identified. (1) The amount of IL-2 in the supernatants derived from tolerant cultures declines prematurely compared to normal cultures. This premature decline in IL-2 production was due neither to a lower frequency of Th cells as judged by limit dilution analysis nor to an increase in IL-2R expression on tolerant lymphocytes as measured by FACS analysis. (2) IL-4 and presumably IL-5 can be demonstrated in supernatants of tolerant, but not normal, lymphocytes stimulated by the tolerogen. Thus although lymphocytes from MLR-positive tolerant mice generate substantial quantities of lymphokines in response to the tolerogen, the pattern of lymphokine production is unusual when compared to that of normal lymphocytes. These results are inconsistent with the notion that a global lack of helper activity, per se, is responsible for the maintenance of tolerance in these mice and furthermore suggest that tolerance could be the result of "inappropriate" lymphokine production.