HIV-1TransInfection of CD4⁺T Cells by Professional Antigen Presenting Cells

Abstract

Since the 1990s we have known of the fascinating ability of a complex set of professional antigen presenting cells (APCs; dendritic cells, monocytes/macrophages, and B lymphocytes) to mediate HIV-1 trans infection of CD4+ T cells. This results in a burst of virus replication in the T cells that is much greater than that resulting from direct, cis infection of either APC or T cells, or trans infection between T cells. Such APC-to-T cell trans infection first involves a complex set of virus subtype, attachment, entry, and replication patterns that have many similarities among APC, as well as distinct differences related to virus receptors, intracellular trafficking, and productive and nonproductive replication pathways. The end result is that HIV-1 can sequester within the APC for several days and be transmitted via membrane extensions intracellularly and extracellularly to T cells across the virologic synapse. Virus replication requires activated T cells that can develop concurrently with the events of virus transmission. Further research is essential to fill the many gaps in our understanding of these trans infection processes and their role in natural HIV-1 infection.

CD40L Induces Functional Tunneling Nanotube Networks Exclusively in Dendritic Cells Programmed by Mediators of Type 1 Immunity

“…Interestingly, HIV-1 infection does not induce these structures in infected CD4 + T cells, but their existing TNTs support the direct transfer of HIV-1 to uninfected T cells over long distances (16). DC can act as a ‘Trojan horse’ by sequestering intact HIV-1 virions and mediating trans -infection of CD4 + T cells by transmitting virions across the virologic synapse (40). In this report, we demonstrate that HIV-1-like particles can be directly transferred from DC to DC via CD40L-induced TNT networks.…”

Trophic Effects of Mesenchymal Stem Cells in Tissue Regeneration

“…[171][172][173] Ca 2+ and intercellular vesicles could also be transported through MNTs between cells. 161,174,175 Transfer of miRNA through MNTs has been described in cancer cells, but has to be investigated if this function is also present in immune cells or in MSCs. 176 MNTs were found to transport porous silicon microparticles, so that they may be involved in the dispersion of therapeutic agents at the site of diseased tissue.…”

Snapin promotes HIV ‐1 transmission from dendritic cells by dampening TLR 8 signaling

“…These observations explain how HIV‐1 avoids innate sensing during uptake into DCs and in the cytosol. But it remains unknown how it evades detection within endosomes, and how internalized HIV‐1 is effectively transferred to CD4 + T cells during trans ‐infection (McDonald, 2010; Rinaldo, 2013). …”