Background: Cell-mediated immunity including T-cells (T helper and cytotoxic) plays an essential role in efficient antiviral responses against coronavirus disease-2019 (COVID-19). Therefore, in this study, we evaluated the ratio and expression of CD4 and CD8 markers in COVID-19 patients to clarify the immune characterizations of CD4 and CD8 T-cells in COVID-19 patients. Methods: Peripheral blood samples of 25 COVID-19 patients and 25 normal individuals with similar age and sex as the control group were collected. White blood cells, platelets, and lymphocytes were counted and CD4 and CD8 T lymphocytes were evaluated by flow cytometry. Results: The number of white blood cells, lymphocytes, and platelets were reduced significantly in COVID-19 patients (P < 0.05). The difference in CD4:CD8 ratio, CD4 T-cell frequency, CD8 T-cell frequency, and CD4 mean fluorescence intensity (MFI) was not significant between COVID-19 patients and healthy individuals (P > 0.05); however, the CD8 MFI increased significantly in COVID-19 infected patients (P < 0.05). Conclusion: Although, there is no significant difference in the ratio of CD4 to CD8 between two groups, the expression level of CD8 in COVID-19 patients was significantly higher than the normal individuals. This result suggested that the cellular immune responses triggered by COVID-19 infection were developed through overexpression of CD8 and hyperactivation of cytotoxic T lymphocytes.

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MicroRNAs play an important role in neuronal development and function. miR-124 is the most abundantly expressed miRNA in the nervous system. Several different mRNA targets have been proposed for miR-124, but the precise function of endogenous miR-124 and its mRNA targets remain to be further elucidated. Specificity protein 1 (Sp1) is a transcription factor that plays key roles in many cell processes including cell cycle. However, this transcription factor is nearly absent in differentiated neurons and a remarkable suppression of Sp1 expression was shown after neurogenesis. Since miR-124 is expressed abundantly in neurons and because Sp1 levels decrease during neurogenesis, it is possible that miR-124 could regulate the expression of Sp1 during neuronal development. Therefore, the aim of the present study was to evaluate the putative targeting of Sp1 by miR-124. Overexpression of miR-124 using a plasmid coding for pri-miR-124 in HEK293 cells decreased the expression of Sp1 mRNA. The results of dual-luciferase reporter assay demonstrated that miR-124 directly targeted the 3'-untranslated regions of Sp1 mRNA. To evaluate whether Sp1 expression was regulated by miR-124 during the process of neuronal differentiation, Adipose-derived mesenchymal stem cells (A-MSCs) were differentiated into neuron-like cells. The results of qPCR analysis showed that with the gradual increase of miR-124 expression during neurogenesis, the expression of Sp1 mRNA decreased accordingly. In summary, this study demonstrated for the first time that miR-124 is able to suppress Sp1 expression, which in turn affected the neuronal differentiation of mesenchymal stem cells.

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Accurate identification of dermatophyte species is important both for epidemiological studies and for implementing antifungal treatment strategies. Although nucleic acid amplification-based assays have several advantages over conventional mycological methods, a major disadvantage is their high cost. The aim of this study was to develop a rapid and accurate real-time PCR-based high-resolution melting (HRM) assay for differentiation of the most common dermatophyte species. The oligonucleotide primers were designed to amplify highly conserved regions of the dermatophyte ribosomal DNA. Analysis of a panel containing potentially interfering fungi demonstrated no cross reactivity with the assay. To evaluate the performance characteristics of the method, a total of 250 clinical isolates were tested in comparison with the long-established PCR-RFLP method and the results were reassessed using DNA sequencing, as the reference standard method. The assay is able to type dermatophytes using normalised melting peak, difference plot analysis or electrophoresis on agarose gel methods. The results showed that, in comparison to PCR-RFLP, the developed HRM assay was able to differentiate at least 10 common dermatophytes species with a higher speed, throughput and accuracy. These results indicate that the HRM assay will be a useful sensitive, high throughput and cost-effective method for differentiating the most common dermatophyte species.