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Major histocompatibility complex (MHC), which plays a major biological function in immune response, is generally associated with so many human disease. During recent years a new clinical relevance of MHC disease. On the other hand there is a strong correlation between some autoimmune diseases and MHC system such as in some allergic abnormalities and its relation with HLA antigens. In order to investigate this concept 30 atypic asthmatic patients and 100 healthy controls were selected. Human leukocyte antigen (HLA) typing was performed by standard NIH procedures and the results analyzed. The frequency of HLA-A2, A11, Aw19 and HLA-B51 decreased in atypic asthmatic patients with no association recorded significantly between HLA-C and allergic asthma. The results of our study indicated that there was a significant relationship between allergic asthma and HLA-I antigens.

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Background and Objective: Sphingosine-1-phosphate (S1P) is involved in regulation of proliferation, differentiation, hypertrophy and anti-apoptosis and activation of satellite cells. This study was done to evaluated the effect of 8 weeks resistance training on sphingosine-1-phosphate level and gene expression of SK1 enzyme, isoforms of MHCs in skeletal muscles of male Wistar rats. Materials and Methods: This experimental study was done on Twenty four 8-week-old 190-250 gr male Wistar rats. The rats were allocated randomly into control (N=12) and training (N=12) groups. Resistance training was done using a 1 meter height ladder with 2 cm grid with an 85 degree incline, and weights attached to rat's tails. The content of S1P present in the chloroform layer was determined by means of high performance liquid chromatography (HPLC). Determination of relative mRNA expression was performed by Real-time PCR. Data were analyzed using SPSS-17, Kolmogorov-Smirnov and independent t-test. Results: Resistance exercise training increased the total content of S1P in FHL (fast-twitch) and soleus (slow-twitch) muscles in comparison with control group (P<0.05). Resistance exercise training changed the gene expression of FHL SK1, SOL SK1, FHL MHC I, Sol MHC I, FHL MHC IIa, Sol MHC IIa, FHL MHC IIb, Sol MHC IIb, FHL MHC IIx, Sol MHC IIx in comparison with control group (P<0.05). Conclusion: This study showed that S1P level and gene expression of SK1, MHCs increased at skeletal muscles after training.

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Background and Objective: Breast cancer is one of the most common diseases worldwide and the second leading cause of death among women. Immune responses play a critical role in inhibiting the onset and progression of this disease. Given the important role of T lymphocytes in identifying and preventing the spread of breast cancer tumor cells, this study was conducted to simultaneously evaluate the regulatory molecules CXC chemokine receptor 3 (CXCR3), programmed cell death protein 1 (PD-1), natural killer group 2 member D (NKG2D), and transforming growth factor beta 1 receptor II (TGF-βRII) on T lymphocytes of newly diagnosed breast cancer patients.
Methods: This case-control study was performed on 26 newly diagnosed breast cancer patients (mean age = 46.2±9.5 years) admitted to the Fifth Azar Educational-Therapeutic Center in Gorgan, Iran, and 12 non-breast cancer individuals (mean age = 42.9±9.9 years) selected from the staff and students of Golestan University of Medical Sciences during 2018-2019. First, blood sampling was performed and peripheral blood mononuclear cells (PBMCs) were isolated. Then, using flow cytometry, different cell populations were evaluated for the expression of CXCR3, PD-1, NKG2D, and TGF-βRII. Plasma levels of interferon gamma (IFN-γ) and major histocompatibility complex class I chain related gene-A (MIC-A) were measured by enzyme-linked immunosorbent assay (ELISA).
Results: The mean percentage of T lymphocyte population in newly diagnosed breast cancer patients was significantly lower compared to healthy individuals (P<0.05). Also, the mean percentage of T lymphocytes expressing PD-1 and TGF-βRII was higher in the case group compared to the control group, while the expression of NKG2D and CXCR3 showed lower levels (P<0.05). The results of comparing plasma concentrations of IFN-γ and MIC-A indicated that the case group had higher levels of MIC-A than the control group (P<0.05); however, no statistically significant difference was found regarding IFN-γ.
Conclusion: It seems that the increased expression of TGF-βRII and PD-1 along with the decreased expression of NKG2D and CXCR3 and the reduced level of MIC-A in newly diagnosed breast cancer patients may be related to upregulation and potent suppression of T lymphocyte immunity and their dysfunction in breast cancer disease.