Are Basophils and Mast Cells Masters in HIV Infection?

Abstract

The World Health Organization AIDS epidemic update estimates that more than 37 million people are living with HIV infection. Despite the unprecedented success of antiretroviral treatments, significant challenges remain in the fight against HIV. In particular, how uninfected cells capture HIV and transmit virions to target cells remains an unanswered question. Tissue mast cells and peripheral blood basophils can be exposed to virions or HIV products during infection. Several HIV proteins (i.e., envelope glycoproteins gp120 and gp41, Tat, and Nef) can interact with distinct surface receptors expressed by human basophils and mast cells and modulate their functional responses at different levels. Additionally, several groups have provided evidence that human mast cells can be infected in vitro, as well as in vivo, by certain strains of HIV. Recently, it has been demonstrated that basophils purified from healthy donors and intestinal mast cells can efficiently capture HIV on their cell surface and, cocultured with CD4⁺ T cells, they can transfer the virus to the cocultured cells leading to infection. Direct contact between human basophils or intestinal mast cells and CD4⁺ T cells can mediate viral trans-infection of T cells through the formation of viral synapses. Thus, basophils and mast cells can provide a cellular basis for capturing and then spreading viruses throughout the body. Collectively, these findings suggest that human basophils and mast cells play a complex and possibly distinct role in HIV infection, warranting further investigations.

An Evaluation to Determine the Strongest CD4 Count Covariates during HIV Disease Progression in Women in South Africa

“…Although they are the least abundant leucocytes [ 88 ], our study has found basophils to explain the greatest variation in the CD4 + count following the lymphocytes. However, the direct contact between human basophils and CD4 + T cells is known to mediate viral trans-infection of T cells through the formation of viral synapses [ 89 , 90 ]. Also, the presence of basophils and other white blood cells in the blood is affected by underlying infection [ 91 ].…”

Human mast cells and basophils—How are they similar how are they different?

“…Basophils have long been marginalized in immunological studies and they were erroneously regarded as minor relatives of mast cells. Recent advances in analytical tools for basophils have highlighted the non‐redundant roles of basophils not only in allergic inflammation but also in autoimmune disorders, microbial infections, immunodeficiencies, and cancer . In murine models, there is convincing evidence of the heterogeneity of basophils expressing the TSLP receptor or the IL‐3 receptor .…”

“…Human mast cells and basophils were first described and named in 1878 and 1879, respectively, by Paul Ehrlich who discovered their property to be stained by specific dyes . Mast cells and basophils are important cells of the immune system with critical role in allergic and autoimmune disorders, microbial infections, cardiovascular diseases, immunodeficiencies, and cancer …”

Physiological Roles of Mast Cells: Collegium Internationale Allergologicum Update 2019

“…Several bacterial proteins can induce the release of mediators (e.g., histamine, PGD 2 , TNF-α, and cysteinyl leukotrienes) from human mast cells [22, 117-119]. Initial studies with KIT mutant mice showed that mast cells are crucial for protection against enterobacterial infection in the cecal ligation and puncture (CLP) model of sepsis [120, 121].…”