Zika virus (ZIKV) persists in the semen of male patients, a first for flavivirus infection. Here, we demonstrate that ZIKV can induce inflammation in the testis and epididymidis, but not in the prostate or seminal vesicle, and can lead to damaged testes after 60 days post-infection in mice. ZIKV induces innate immune responses in Leydig, Sertoli, and epididymal epithelial cells, resulting in the production of pro-inflammatory cytokines/chemokines. However, ZIKV does not induce a rapid and abundant cytokine production in peritubular cell and spermatogonia, suggesting that these cells are vulnerable for ZIKV infection and could be the potential repositories for ZIKV. Our study demonstrates a correlation between ZIKV and testis infection/damage and suggests that ZIKV infection, under certain circumstances, can eventually lead to male infertility.

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Background: This meta-analysis aimed to estimate the association of human immunodeficiency virus (HIV) infection and risk of coronavirus disease 2019 (COVID-19) mortality. Methods: We systematically retrieved articles published on HIV infection and risk of COVID-19 mortality through PubMed, EMBase, China National Knowledge Infrastructure, WanFang, and Chongqing VIP databases using a predefined search strategy from December 1, 2019 to January 31, 2021. Newcastle–Ottawa Scale (NOS) was used to assess the quality of the included studies. Cochran Q test and I 2 statistics were quantified to measure heterogeneity. Odds ratio (OR) and 95% confidence intervals (CI) were computed and displayed in the form of forest plots. Subgroup analysis was performed to explore the source of heterogeneity. Funnel plot, Begg test, and Egger test were used to assess potential publication bias. Stata software version 11.0 was used to analyze all the statistical data. Results: We included 10 studies with 18,122,370 COVID-19 patients, of whom 41,113 were with HIV infection and 18,081,257 were without HIV infection. The pooled overall results suggested that people living with HIV infection had a higher risk of mortality from COVID-19 than those without HIV infection (OR = 1.252, 95% CI 1.027–1.524). Subgroup analysis showed that people living with HIV infection had a higher risk of COVID-19 mortality than those without HIV infection in the United States (OR = 1.520, 95% CI 1.252–1.845) and in South Africa (OR = 1.122, 95% CI 1.032–1.220); however, no significant association was found in the United Kingdom (OR = 0.878, 95% CI 0.657–1.174). Conclusion: Patients with HIV infection should be the emphasis population to prevent the risk of mortality during the clinical treatment of COVID-19 patients.

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P2X7 receptor (P2X7R) is highly expressed on immune cells, triggering the release of cytokines and regulating autoimmune responses. To investigate P2X7R surface expression on T helper (Th) 1, Th17, and regulatory T (Treg) cells in patients with systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA) and correlations with disease activity, 29 SLE and 29 RA patients and 18 healthy controls (HCs) were enrolled. We showed that SLE and RA patients had significantly higher levels of plasma cytokines (IFN-g, IL-1b, IL-6, IL-17A, and IL-23), frequencies of Th1 and Th17 cells, and expression of P2X7R on Th1 and Th17 than HCs, and the Th17/Treg ratio was significantly increased, whereas Treg cell levels were significantly decreased. The Ca 2+ influx increase following BzATP stimulation was significantly higher in CD4 + PBMCs from SLE and RA patients than in HCs. Blood levels of shed P2X7R were increased in SLE and RA patients. Furthermore, 28-joint Disease Activity Score and SLE Disease Activity Index score showed negative correlations with Treg cell levels and positive correlations with Th17/Treg ratio and Th17 cell P2X7R expression. Interestingly, Th17 cell P2X7R expression was closely correlated with IL-1b, C-reactive protein, the erythrocyte sedimentation rate, anticyclic citrullinated peptide Abs, albumin, and C4. These data indicate that increased Th17 cell P2X7R expression is functionally and positively related to disease activity and some inflammatory mediators in SLE and RA patients, and P2X7R could be critical in promoting the Th17 immune response and contributing to the complex pathogenesis of SLE and RA.

Serum amyloid A (SAA), one of the major highly conserved acute-phase proteins in most mammals, is predominantly produced by hepatocytes and also by a variety of cells in extrahepatic tissues. It is well-known that the expression of SAA is sharply increased in bacterial infections. However, the exact physiological function of SAA during bacterial infection remains unclear. Herein, we showed that SAA expression significantly increased in abscesses of Staphylococcus aureus cutaneous infected mice, which exert direct antibacterial effects by binding to the bacterial cell surface and disrupting the cell membrane in acidic conditions. Mechanically, SAA disrupts anionic liposomes by spontaneously forming small vesicles or micelles under acidic conditions. Especially, the N-terminal region of SAA is necessary for membrane disruption and bactericidal activity. Furthermore, we found that mice deficient in SAA1/2 were more susceptible to infection by S. aureus. In addition, the expression of SAA in infected skin was regulated by interleukin-6. Taken together, these findings support a key role of the SAA in host defense and may provide a novel therapeutic strategy for cutaneous bacterial infection.

There is still no animal model available that can mimic all the cognitive, behavioral, biochemical, and histopathological abnormalities observed in patients with Alzheimer's disease (AD). We undertook to consider the interaction between genetic factors, including amyloid precursor protein (APP) and presenllin-I (PSI), and environmental factors, such as Aluminum (AI) in determining susceptibility outcomes when studying the pathogenesis of AD. In this article, we provide an AD model in APP/ PSI transgenic mice triggered by AI. The animal model was established via intracerebral ventricular microinjection of aluminum chloride once a day for 5 days in APP/PSI transgenic mice. Twenty wild type (WT) mice and 20 APP/PSI transgenic (TG) mice were separately divided into 2 groups (control and Al group), and a stainless steel injector with stopper was used for microinjection into the left-lateral cerebral ventricle of each mouse. The Morris water maze task was used to evaluate behavioral function of learning and memory ability on the 20th day after the last injection. This AD model's brain was analyzed by: (1) amyloid p immunohistochemical staining; (2) Tunnel staining; (3) apoptotic rates; (l:a) caspase-3 gene expression. Here, decrease of cognitive ability and neural cells loss were shown in APP/ PSI transgenic mice exposed to AI, which were more extensive than those in APP/PSI TG alone and WT mice exposed to Al alone. These findings indicate that there is a close relationship between overexpression of APP and PSI genes and Al overload. It is also suggested that APP/PSI TG mice exposed to Al have potential value for improving AD models.Development of adequate animal models mimicking all stages of Alzheimer's disease (AD) progression and merging convergent pathways of pathogenesis represents a need for research on AD. Amyloid plaques and neurofibrillary tangles are the two most widely recognized hallmarks of AD, the molecular events pertaining to their formation have been under intensive study for over a decade. A number of AD models rely on information gathered from inherited familial forms including various human pedigrees of gene mutations in amyloid precursor protein (APP), presenilin-I (PSI) and presenilin-2 (PS2) (l, 2). Despite their undoubted value, transgenic AD mice show a number ofpitfalls (3). That is, they fail to model the progressive stages of the disease or to show significant neuron loss.Environmental toxins as risk factors may contribute to the development ofAD (3). Aluminum

A proper balance between androgen and oestrogen is fundamental for normal male reproductive development and function in both animals and humans. This balance is governed by the cytochrome P450 aromatase, which is expressed also under spatio-temporal control. Oestrogen receptors ERα and/or ERβ, together with the membrane-associated G-protein-coupled functional ER (GPER), mediate the effects of oestrogen in the testis. Oestrogen action in male reproduction is more complex than previously predicted. The androgen/oestrogen balance and its regulation in the masculinisation programming window (MPW) during foetal life is the most critical period for the development of the male reproductive system. If this balance is impaired during the MPW, the male reproductive system may be negatively affected. Recent data from genetically modified mice and human infertile patients have shown that oestrogens may promote the engulfment of live Leydig cells by macrophages leading to male infertility. We also discuss recent data on environmental oestrogen exposure in men and rodents, where a rodent-human distinction is crucial and analyse some aspects of male fertility potentially related to impaired oestrogen/androgen balance.