Pathogenic Th cell subsets in chronic inflammatory diseases

T Lymphocyte Subsets Profile and Toll-Like Receptors Responses in Patients with Herpes Zoster

Purpose

Herpes zoster (HZ) is caused by the varicella-zoster virus (VZV), and 20% of healthy humans and 50% of people with immune dysfunction have a high probability of suffering from HZ. This study aimed to screen dynamic immune signatures and explore the potential mechanism during HZ progression.

Patients and Methods

Peripheral blood samples from 31 HZ patients and 32 age-sex-matched healthy controls were collected and analyzed. The protein levels and gene levels of toll-like receptors (TLRs) were detected in peripheral blood mononuclear cells (PBMCs) by flow cytometry and quantitative real-time PCR. Further, the characteristics of T cell subsets and cytokines were detected via a cytometric bead array.

Results

Compared to healthy controls, the mRNA levels of TLR2, TLR4, TLR7, and TLR9 mRNA in PBMCs were significantly increased in HZ patients. The protein level of TLR4 and TLR7 was significantly increased in HZ patients, but the levels of TLR2 and TLR9 were dramatically decreased. The CD3+ T cells were constant in HZ and healthy controls. CD4+ T cells were decreased in HZ patients, while CD8+ T cells were increased, resulting in an improved CD4+/CD8+ T cells ratio. Further, it was found that Th2 and Th17 were not changed, but the decreased Th1 and upregulated Treg cells were found in HZ. The Th1/Th2 and Th17/Treg ratios were significantly decreased. Last, the levels of IL-6, IL-10, and IFN-γ were significantly increased, but IL-2, IL-4, and IL-17A had no significant changes.

Conclusion

The dysfunction of host's lymphocytes and activation of TLRs in PBMCs were the important mechanism in varicella-zoster virus induced herpes zoster. TLRs might be the core targets for the therapy drug development in treating HZ.

A New Role for Conivaptan in Ulcerative Colitis in Mice: Inhibiting Differentiation of CD4+T Cells into Th1 Cells

BACKGROUND

Conivaptan, a nonselective antagonist of vasopressin receptors V1a and V2, is the first drug of this class to be used for treating euvolemic and hypervolemic hyponatremia. Recently, increasing evidence supports the involvement of vasopressin in immune responses.

AIMS

In this study, we investigated the effect of conivaptan on the modulation of CD4⁺ T cell homeostasis and the progression of experimental colitis.

METHODS

The expression of the V1a receptor on CD4⁺ T cells was detected by immunofluorescence and western blot. The subset of isolated CD4⁺ T cells were examined after arginine vasopressin (AVP) incubation. CD4⁺ T cells were injected into DNBS-induced mice through the tail vein. The severity of colitis was evaluated according to weight, disease activity index (DAI), and morphological injury. Intracellular Ca²⁺ ([Ca²⁺]_i) signaling in CD4⁺ T cells was measured using the Fluo-3 AM loading method. T-bet and IFN-γ mRNAs in the colon were detected by real-time polymerase chain reaction (qPCR).

RESULTS

We found that CD4⁺ T cells expressed the V1a receptor. Activation of the V1a receptor significantly promoted the differentiation of CD4⁺ T cells into T helper 1 (Th1) cells. This process was blocked by conivaptan treatment. However, the activation of the V1a receptor did not evoke an increase in [Ca²⁺]_i in CD4⁺ T cells. Notably, conivaptan markedly alleviated body weight loss, pathological damage, and expression of T-bet and IFN-γ in the colon of DNBS-treated mice.

CONCLUSIONS

For the first time, we report that conivaptan attenuated colitis by inhibiting the differentiation of CD4⁺ T cells into Th1 cells. Mechanistically, the anti-inflammatory role of conivaptan is independent of [Ca²⁺]_i.

Targeting the balance of T helper cell responses by curcumin in inflammatory and autoimmune states

CD4⁺ T helper (Th) cells are a crucial player in host defense but under certain conditions can contribute to the pathogenesis of inflammatory and autoimmune diseases. Beside the Th1/Th2 subset, several additional Th subsets have been identified, each with a distinctive transcription factor, functional properties, signature cytokine profile, and possible role in the pathophysiology of diseases. These newer Th subsets include Th17, regulatory Th cells (Tregs), and more recently, Th9, Th22, and follicular T helper cells. Interestingly, imbalance of Th subsets contributes to the immunopathology of several disease states. Therefore, targeting the imbalance of Th subsets and their signature cytokine profiles by a safe, effective and inexpensive nutraceutical agent such as curcumin could be helpful to treat autoimmune and inflammatory diseases. In this study different Th subsets and how the imbalance of these subsets could promote pathology of several diseases has been reviewed. Furthermore, the role of curcumin in this process will be discussed and the impact of targeting Th subsets by curcumin.

Determination of the Th1, Th2, Th17, and Treg cytokine profile in patients with chronic Chagas heart disease and systemic arterial hypertension

Chronic Chagas heart disease (CCHD affects about 30% of patients with chronic Chagas disease (CCD). Systemic arterial hypertension (SAH) afflicts about 25% of patients with CCD. The association of CCHD with SAH (CCHD-SAH) predisposes patients to develop chronic heart failure. The role of cytokines in disease progression in patients with CCHD-SAH is unknown. Accordingly, the aim of this study was to evaluate the plasma levels of cytokines expressing the Th1, Th2, Th17 pattern, as well as Treg cytokines, TNF-alpha, IL-1β, IL-8, IL-7 in patients with SAH-CCHD to get insight into the immunomodulation process in patients with this condition. Fifteen patients with CCHD, 22 patients with CCHD-SAH, and 28 controls were studied. All patients underwent history-taking, physical examination, 12-lead resting ECG, chest X-ray, and Doppler-echocardiogram. Ten of 15 (66%) patients with CCHD, and 16 of 22 (73%) patients with CCHD-SAH had decreased left ventricular ejection fraction (p > 0.05). Cytokines levels were performed on plasma samples using the ELISA method. Overall, proinflammatory, anti-inflammatory, and regulatory cytokine levels were increased in patients with CCHD-SAH in comparison to patients with CCHD and controls. However, such a difference was higher regarding IL-2, IL-5, IL-17, IL-12, and TNF-alpha cytokine levels, respectively. Cytokine levels were higher in CCHD patients in comparison to controls. Patients with CCHD-SAH have increased plasma levels of pro-inflammatory, anti-inflammatory, and regulatory cytokines in comparison with CCHD patients, thus suggesting a higher level of immunomodulation in patients with CCHD-SAH.

Insulin resistance in patients with recurrent pregnancy loss is associated with lymphocyte population aberration

This study was designed to investigate the relationship of insulin resistance (IR) and cellular immune abnormalities associated with women with recurrent pregnancy loss (RPL). Women with RPL were divided into two groups according to their homeostasis model assessment for IR (HOMA-IR) scores. The IR group received metformin approximately 3 months before pregnancy. The percentage of lymphocyte subsets and other blood biochemical indices were tested. The HOMA-IR and fasting serum insulin levels were related to the percentage of lymphocyte subsets. The women with RPL had higher CD3⁺ and CD3⁺CD4⁺ cell levels while CD56⁺CD16⁺cell levels were lower. A higher likelihood of cellular immune abnormalities was observed. Women with normal lymphocyte subsets had normal pregnancy outcomes. Metformin significantly downregulated CD3⁺ and CD3⁺CD4⁺ cells and improved pregnancy outcomes. IR was associated with cellular immune abnormalities in RPL. The data suggests that metformin affected the immune/inflammatory response, which may regulate the cellular immune balance and improve pregnancy outcomes. Abbreviations RPL: recurrent pregnancy loss; IR insulin resistance; HOMA-IR: homeostasis model assessment for IR.