Retrovirology (Dec 2012)

Placental Hofbauer cells limit HIV-1 replication and potentially offset mother to child transmission (MTCT) by induction of immunoregulatory cytokines

  • Johnson Erica L,
  • Chakraborty Rana

DOI
https://doi.org/10.1186/1742-4690-9-101
Journal volume & issue
Vol. 9, no. 1
p. 101

Abstract

Read online

Abstract Background Despite readily detectable levels of the HIV-1 (co)-receptors CD4, CCR5 and DC-SIGN on placental macrophages (Hofbauer Cells [HCs]), the rate of HIV-1 infection in utero in the absence of interventions is only 7% of exposed infants. Here, we examine the replication kinetics of human HCs to the primary isolate HIV-1BaL. We also determined the infectivity of HIV-1-exposed HCs by co-culturing with isolated cord and peripheral blood mononuclear cells [CBMCs, PBMCs]. To understand the limiting nature of HCs to HIV-1 replication, we examined the effect of endogenously secreted cytokines on replication kinetics. Results HCs have reduced ability to replicate HIV-1 in vitro (p gag and env), which may account for lower levels of HIV-1 replication. Un-stimulated HCs constitutively express significantly higher levels of regulatory cytokines, IL-10 and TGF-β, compared to MDMs (p in vitro. Conclusion HCs have reduced ability to replicate and disseminate R5-tropic HIV-1BaLin vitro and potentially offset mother to child transmission (MTCT) of HIV-1 by the induction of immunoregulatory cytokines. Despite the potential for migration and infectivity, HCs are not present in the neighboring fetal circulation. These results implicate HCs as important mediators of protection at the feto-maternal interface during ongoing HIV-1 exposure.

Keywords