Quantitative analysis of the processes and signaling events involved in early HIV-1 infection of T cells

PLoS One. 2014 Aug 8;9(8):e103845. doi: 10.1371/journal.pone.0103845. eCollection 2014.

Abstract

Lymphocyte invasion by HIV-1 is a complex, highly regulated process involving many different types of molecules that is prompted by the virus's association with viral receptors located at the cell-surface membrane that culminates in the formation of a fusion pore through which the virus enters the cell. A great deal of work has been done to identify the key actors in the process and determine the regulatory interactions; however, there have been no reports to date of attempts being made to fully understand the system dynamics through a systemic, quantitative modeling approach. In this paper, we introduce a dynamic mathematical model that integrates the available information on the molecular events involved in lymphocyte invasion. Our model shows that moesin activation is induced by virus signaling, while filamin-A is mobilized by the receptor capping. Actin disaggregation from the cap is facilitated by cofilin. Cofilin is inactivated by HIV-1 signaling in activated lymphocytes, while in resting lymphocytes another signal is required to activate cofilin in the later stages in order to accelerate the decay of the aggregated actin as a restriction factor for the viral entry. Furthermore, stopping the activation signaling of moesin is sufficient to liberate the actin filaments from the cap. The model also shows the positive effect of gelsolin on actin capping by means of the nucleation effect. These findings allow us to propose novel approaches in the search for new therapeutic strategies. In particular, gelsolin inhibition is seen as a promising target for preventing HIV-1 entry into lymphocytes, due to its role in facilitating the capping needed for the invasion. Also it is shown that HIV-1 should overcome the cortical actin barrier during early infection and predicts the different susceptibility of CD4+ T cells to be infected in terms of actin cytoskeleton dynamics driven by associated cellular factors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actin Depolymerizing Factors / metabolism
  • CD4-Positive T-Lymphocytes / virology*
  • Filamins / metabolism
  • Gelsolin / metabolism
  • HIV Infections / physiopathology*
  • HIV-1 / physiology*
  • Humans
  • Microfilament Proteins / metabolism
  • Models, Biological*
  • Signal Transduction / physiology*
  • Virus Internalization*

Substances

  • Actin Depolymerizing Factors
  • Filamins
  • Gelsolin
  • Microfilament Proteins
  • moesin

Grants and funding

This work was funded by research grants from the Spanish MICINN, Ref. No. BIO2011-29233-C02-02 and the Agencia Canaria de Investigación, Innovación y Sociedad de la Información, Ref. No. PIL2071001. AV-F is supported by the European Regional Development Fund, SAF2011-24671 (Ministerio de Ciencia e Innovación, Spain), 24-0740-09 (Fundación para la Investigación y la Prevención del SIDA en España (FIPSE), Spain), ProID20100020 (Agencia Canaria de Investigación, Innovación y Sociedad de la Información, Canary Island Government, Spain), and RIS-RETIC (Red Nacional de Investigación en SIDA, ISCIII, Spain) associated RD12/0017/0034 grants. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.