Genome-wide screening of SARS-CoV-2 infection-related genes based on the blood leukocytes sequencing data set of patients with COVID-19.

Coronavirus disease 2019 (COVID-19) is a global epidemic disease caused by a novel virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing serious adverse effects on human health. In this study, we obtained a blood leukocytes sequencing data set of COVID-19 patients from the GEO database and obtained differentially expressed genes (DEGs). We further analyzed these DEGs by protein-protein interaction analysis and Gene Ontology enrichment analysis and identified the DEGs closely related to SARS-CoV-2 infection. Then, we constructed a six-gene model (comprising IFIT3, OASL, USP18, XAF1, IFI27, and EPSTI1) by logistic regression analysis and calculated the area under the ROC curve (AUC) for the diagnosis of COVID-19. The AUC values of the training group, testing group, and entire group were 0.930, 0.914, and 0.921, respectively. The six genes were highly expressed in patients with COVID-19 and positively correlated with the expression of SARS-CoV-2 invasion-related genes (ACE2, TMPRSS2, CTSB, and CTSL). The risk score calculated by this model was also positively correlated with the expression of TMPRSS2, CTSB, and CTSL, indicating that the six genes were closely related to SARS-CoV-2 infection. In conclusion, we comprehensively analyzed the functions of DEGs in the blood leukocytes of patients with COVID-19 and constructed a six-gene model that may contribute to the development of new diagnostic and therapeutic ideas for COVID-19. Moreover, these six genes may be therapeutic targets for COVID-19.

[Advances in immune escape mechanism of Ureaplasma species: Review].

Ureaplasma urealyticum and Ureaplasma parvum are the most common Ureaplasma species causing repeated or persistent infection of the urogenital tract. The host can mobilize innate and adaptive immunity to defend and eliminate pathogens. However, under certain conditions, the host's immune protection cannot completely clear Ureaplasma species. Ureaplasma species have evolved a complex and sophisticated escape mechanism in the long-term defense against host immune protection. This article summarizes the research progress on Ureaplasma species' immune escape mechanism from several aspects such as evading host autophagy mechanism, antagonizing host nutritional immunity and regulating host cell gene expression.

GrpE Immunization Protects Against Ureaplasma urealyticum Infection in BALB/C Mice.

Nucleotide exchange factor (GrpE), a highly conserved antigen, is rapidly expressed and upregulated when Ureaplasma urealyticum infects a host, which could act as a candidative vaccine if it can induce an anti-U. urealyticum immune reaction. Here, we evaluated the vaccine potential of recombinant GrpE protein adjuvanted by Freund's adjuvant (FA), to protect against U. urealyticum genital tract infection in a mouse model. After booster immunization in mice with FA, the GrpE can induced both humoral and cellular immune response after intramuscular injection into BALB/c mice. A strong humoral immune response was detected in the GrpE-immunized mice characterized by production of high titers of antigen-specific serum IgG (IgG1, IgG2a, and IgG3) antibodies. At the same time, the GrpE also induced a Th1-biased cytokine spectrum with high levels of IFN-γ and TNF-α after re-stimulation with immunogen GrpE in vitro, suggesting that GrpE could trigger the Th1 response when used for vaccination in the presence of FA. Although GrpE vaccination in the presence of a Th1-type adjuvant-induced had readily detectable Th1 responses, there wasn't increase inflammation in response to the infection. More importantly, the robust immune responses in mice after immunization with GrpE showed a significantly reduced U. urealyticum burden in cervical tissues. Histopathological analysis confirmed that tissues of GrpE-immunized BALB/c mice were protected against the pathological effects of U. urealyticum infection. In conclusion, this study preliminarily reveals GrpE protein as a promising new candidate vaccine for preventing U. urealyticum reproductive tract infection.