HIV Infection and Spread between Th17 Cells

Mechanisms of mucosal immunity at the female reproductive tract involved in defense against HIV infection

Human immunodeficiency virus-1 remains a major global health threat. Since the virus is often transmitted through sexual intercourse and women account for the majority of new infections within the most endemic regions, research on mucosal immunity at the female reproductive tract (FRT) is of paramount importance. At the FRT, there are intrinsic barriers to HIV-1 infection, such as epithelial cells and the microbiome, and immune cells of both the innate and adaptive arms are prepared to respond in case the virus overcomes the first line of defense. In this review, we discuss recent findings on FRT mucosal mechanisms of HIV-1 defense and highlight research gaps. While defense from HIV-1 infection at the FRT has been understudied, current and future research is essential to develop new therapeutics and vaccines that can protect this unique mucosal site from HIV-1.

The Possible Mechanisms of Cu and Zn in the Treatment and Prevention of HIV and COVID-19 Viral Infection

Due to their unique properties and their potential therapeutic and prophylactic applications, heavy metals have attracted the interest of many researchers, especially during the outbreak of COVID-19. Indeed, zinc (Zn) and copper (Cu) have been widely used during viral infections. Zn has been reported to prevent excessive inflammatory response and cytokine storm, improve the response of the virus to Type I interferon (IFN-1), and enhance the production of IFN-a to counteract the antagonistic effect of SARS-CoV-2 virus protein on IFN. Additionally, Zn has been found to promote the proliferation and differentiation of T and B lymphocytes, thereby improving immune function, inhibiting RNA-dependent RNA polymerase (RdRp) in SARS- CoV-2 reducing the viral replication and stabilizing the cell membrane by preventing the proteolytic processing of viral polyprotein and proteases enzymes. Interestingly, Zn deficiency has been correlated with enhanced SARS-CoV-2 viral entry through interaction between the ACE2 receptor and viral spike protein. Along with zinc, Cu possesses strong virucidal capabilities and is known to be effective at neutralizing a variety of infectious viruses, including the poliovirus, influenza virus, HIV type 1, and other enveloped or nonenveloped, single- or double-stranded DNA and RNA viruses. Cu-related antiviral action has been linked to different pathways. First, it may result in permanent damage to the viral membrane, envelopes, and genetic material of viruses. Second, Cu produces reactive oxygen species to take advantage of the redox signaling mechanism to eradicate the virus. The present review focused on Zn and Cu in the treatment and prevention of viral infection. Moreover, the application of metals such as Cu and gold in nanotechnology for the development of antiviral therapies and vaccines has been also discussed.

Incidence and Risks of HIV Infection, Medication Options, and Adverse Effects in Accidental Needle Stick Injuries: A Narrative Review

Accidental needle sticks can lead to infections, including HIV. As scientists have learned more about HIV and its replicative physiology, identification of target sites and novel medications have been developed. HIV is spread throughout the population through contact with blood, semen, and rectal or vaginal secretions of infected individuals. Therefore, it is important in general for healthcare workers to be aware of its transmission modes and ways to minimize exposure. In this regard, even with hospitals providing education, training, and safety protocols, there is a continued infection spread with HIV, especially by accidental needle sticks. There is also a wide variety of testing that can be used for HIV utilizing different methodologies, allowing for improved measurement of infection status. Any person with HIV should be tested to clarify infection status and be educated to minimize future virus spread. The current CDC recommendations for HIV infection treatment are antiretroviral therapies, such as an HIV postexposure prophylaxis regimen, which consists of a cocktail of antiretrovirals and postexposure prophylaxis immediately for occupational exposures, such as accidental needlestick exposure from an HIV infected patient. To decrease accidental HIV stick injuries, there are safety precautions in place, that if followed, would help reduce this incidence. HIV accidental needle stick injuries still happen in the hospital workplace, but with proper education and treatment, if exposed, there is hope to minimize the effects.

Enhanced IL-17 Producing and Maintained Cytolytic Effector Functions of Gut Mucosal CD161+CD8+ T Cells in SIV-Infected Rhesus Macaques

Previous studies have indicated that the loss of CD161-expressing CD4+ Th17 cells is linked to the progression of chronic HIV. These cells are significantly depleted in peripheral blood and gut mucosa of HIV-infected individuals, contributing to inflammation and disruption of the gut barrier. However, the impact of HIV infection on CD161-expressing CD8+ T cells remain unclear. Here, we examined the functions of peripheral blood and mucosal CD161+CD8+ T cells in the macaque model of HIV infection. In contrast to the significant loss of CD161+CD4+ T cells, CD161+CD8+ T cell frequencies were maintained in blood and gut during chronic SIV infection. Furthermore, gut CD161+CD8+ T cells displayed greater IL-17 production and maintained Th1-type and cytolytic functions, contrary to impaired IL-17 and granzyme-B production in CD161+CD4+ T cells of SIV-infected macaques. These results suggest that augmented Th17-type effector functions of CD161+CD8+ T cells during SIV infection is a likely mechanism to compensate for the sustained loss of gut mucosal Th17 cells. Targeting the cytokine and cytolytic effector functions of CD161+CD8+ T cells in the preclinical setting of chronic SIV infection with antiretroviral therapy has implications in the restoration of gut barrier disruption in persons with HIV infection.

Environmental Health and Toxicology: Immunomodulation Promoted by Endocrine-Disrupting Chemical Tributyltin

Tributyltin (TBT) is an environmental contaminant present on all continents, including Antarctica, with a potent biocidal action. Its use began to be intensified during the 1960s. It was effectively banned in 2003 but remains in the environment to this day due to several factors that increase its half-life and its misuse despite the bans. In addition to the endocrine-disrupting effect of TBT, which may lead to imposex induction in some invertebrate species, there are several studies that demonstrate that TBT also has an immunotoxic effect. The immunotoxic effects that have been observed experimentally in vertebrates using in vitro and in vivo models involve different mechanisms; mainly, there are alterations in the expression and/or secretion of cytokines. In this review, we summarize and update the literature on the impacts of TBT on the immune system, and we discuss issues that still need to be explored to fill the knowledge gaps regarding the impact of this endocrine-disrupting chemical on immune system homeostasis.

Unique Profile of Proinflammatory Cytokines in Plasma of Drug-Naïve Individuals with Advanced HIV/TB Co-Infection

HIV-1 infection is characterized by aberrant immune activation, and infection with M. tuberculosis by an unbalanced production of proinflammatory cytokines. The expression of these cytokines in HIV-1/TB coinfection is still understudied. Here, we aimed to compare the production of proinflammatory cytokines in drug-naive patients coinfected with HIV-1 and M. tuberculosis (HIV/TB) compared to patients with respective monoinfections. Plasma samples of patients with HIV/TB coinfection (n = 36), HIV-1 monoinfection (n = 36), and TB monoinfection (n = 35) and healthy donors (n = 36) were examined for the levels of eight proinflammatory cytokines. Their levels were significantly increased in all patient groups compared to healthy donors. At the same time, a drastic decrease in the plasma levels of IFN-γ, TNF-α, Il-1β, IL-15, and IL-17 was detected in patients with HIV/TB coinfection compared to patients with HIV-1 or TB monoinfections. The plasma levels of IL-17 characterized the TB severity: in HIV/TB-coinfected patients with disseminated TB, plasma levels of IL-17 were eight times lower than in patients with less severe TB forms (infiltrative TB or TB of intrathoracic lymph nodes; p < 0.0001). At the same time, HIV/TB-coinfected patients had increased plasma levels of IL-8, IL-12, and IL-18, with the levels of IL-8 correlating with mortality (p < 0.0001). Thus, on the contrary to the patients with HIV-1 or TB monoinfections, HIV/TB-coinfected patients had suppressed production of most of the proinflammatory cytokines associated with antimicrobial immune response, specifically of T-cells involved in the containment of both infections. At the same time, they demonstrated an expansion of proinflammatory cytokines known to originate from both hematopoietic and nonhematopoietic cells, and manifest tissue inflammation. In HIV-1/TB coinfection, this leads to the disruption of granuloma formation, contributing to bacterial dissemination and enhancing morbidity and mortality.