Immunosuppressive Effects of Two Probiotics, Lactobacillus paracasei DSM 13434 and Lactobacillus plantarum DSM 15312, on CD4+ T Cells of Multiple Sclerosis Patients.

T cells play an important role in the development and progression of multiple sclerosis (MS), an autoimmune disease of the central nervous system. In the present study, the immunomodulatory impacts of two Lactobacillus strains, L paracasei DSM 13434 and L plantarum DSM 15312, on the frequency and cytokine production of CD4+ T cells in MS patients were explored. Thirty MS patients were enrolled in this study. The CD4+ T cells were isolated, cultured, and exposed to the media containing cell-free supernatants of L plantarum (group1), L paracasei (group 2), the mixture group of cell-free supernatants of both probiotics (group 3), and vehicle (control) group (group 4). The frequencies of T helper (Th) 1, Th17, Th2, and T regulatory type 1 (Tr1) cells and mean fluorescent intensity (MFI) of the associated cytokines were assessed using flow cytometry. The levels of interleukin 17 (IL-17), transforming growth factor ß (TGF-ß), and interferon-gamma (IFN-γ) cytokines in supernatants of all groups were measured by enzyme-linked immunosorbent assay. The percentage of Th1 cells and the MFI of IFN-γ in Th1 cells (CD4+ IFN-γ+) in all three probiotic treatment groups were significantly decreased compared to the control group. However, no significant changes were observed in the proportion and MFI of Th2, Th17, and Tr1 cells. A significant decrease was observed in IL-17 secretion in the supernatant of cultured CD4+ T cells in all three treatment groups in comparison with control. The levels of TGF-ß and IFN-γ were not significantly different among any of the study groups.  Collectively, cell-free supernatants of the lactobacilli showed an in vitro anti-inflammatory effect. However, further studies are needed to prove the real effects of probiotics on MS.

The Impact of Vitamin D Supplementation on the IFNγ-IP10 Axis in Women with Hashimoto's Thyroiditis Treated with Levothyroxine: A Double-blind Randomized Placebo-controlled Trial.

Hashimoto's thyroiditis (HT) results from chemoattraction of inflammatory cells toward the thyroid gland by inducing the production of interferon-gamma (IFNγ)-induced protein 10 (IP10) by T helper (Th) 1 cells. Vitamin D may suppress the IFNγ-IP10 axis, but this new function of vitamin D has not yet been investigated in HT patients. In an intervention and control group, patients received 50000 IU cholecalciferol or placebo every week for three months, respectively. The CD4+ T cells of 40 patients were isolated, and the mRNA expression levels of vitamin D receptor (VDR), peroxisome proliferator-activated receptors (PPAR)-α, and PPAR-γ genes were determined by real-time PCR. ELISA method was used to determine serum levels of vitamin D, tumor necrosis factor-alpha (TNF-α), IFN-γ, and IP10. Vitamin D levels in the intervention group were significantly higher than in the placebo group after supplementation. PPAR-α and PPAR-γ gene expression levels did not differ significantly between the two groups. The serum levels of IP10, IFNγ, and TNF-α decreased significantly in the vitamin D group, as well as in the placebo group.  During this study, vitamin D levels significantly increased in the intervention group and inflammatory factors decreased. Based on the similar results obtained in the placebo group, further studies with larger sample sizes and longer intervention times are recommended.

Effects of vitamin D supplements on frequency of CD4+ T-cell subsets in women with Hashimoto's thyroiditis: a double-blind placebo-controlled study.

BACKGROUND: Vitamin D is a modulator of immune functions. Investigations on the mechanisms of vitamin D action and pathogenesis of Hashimoto's thyroiditis (HT) have revealed that vitamin D can reduce damages to thyroid cells caused by autoreactive immune cells. METHODS: Totally, 48 female patients with HT disease were introduced to the study by endocrinologists. Patients were divided into two major groups of 24 individuals and treated weekly with 50,000 IU of cholecalciferol (vitamin D group) or placebo (placebo group) using oral administration for 3 months. Eventually, 17 of the 24 patients in each group finished the study. Before and after supplementation, frequencies of Th1, Th17, Th2 and Tr1 cells and mean fluorescent intensity (MFI) of the associated cytokines, including IFN-γ, IL-17, IL-4 and IL-10, were assessed using flow cytometry. Furthermore, gene expression of IL-10 was assessed using real-time PCR. RESULTS: Results of this study showed that cholecalciferol supplementation caused a significant decrease in Th17/Tr1 ratio. The proportion and MFI of Th1, Th2, Tr1 and Th17 cells included no significant changes in vitamin D group, compared to those in placebo group. Expression rate and MFI of IL-10 increased in both groups. This increase was higher in vitamin D group than placebo group with no significance. CONCLUSIONS: In this novel preliminary clinical trial study, supplementation with cholecalciferol in HT patients for 3 months changed the balance of CD4+ T-cell subsets to improve the disease control. However, further studies are necessary to investigate effects of vitamin D on immune functions in HT patients.