Mutational networks of escape from transmitted HIV-1 infection

PLoS One. 2020 Dec 7;15(12):e0243391. doi: 10.1371/journal.pone.0243391. eCollection 2020.

Abstract

Human immunodeficiency virus (HIV) is subject to immune selective pressure soon after it establishes infection at the founder stage. As an individual progresses from the founder to chronic stage of infection, immune pressure forces a history of mutations that are embedded in envelope sequences. Determining this pathway of coevolving mutations can assist in understanding what is different with the founder virus and the essential pathways it takes to maintain infection. We have combined operations research and bioinformatics methods to extract key networks of mutations that differentiate founder and chronic stages for 156 subtype B and 107 subtype C envelope (gp160) sequences. The chronic networks for both subtypes revealed strikingly different hub-and-spoke topologies compared to the less structured transmission networks. This suggests that the hub nodes are impacted by the immune response and the resulting loss of fitness is compensated by mutations at the spoke positions. The major hubs in the chronic C network occur at positions 12, 137 (within the N136 glycan), and 822, and at position 306 for subtype B. While both founder networks had a more heterogeneous connected network structure, interestingly founder B subnetworks around positions 640 and 837 preferentially contained CD4 and coreceptor binding domains. Finally, we observed a differential effect of glycosylation between founder and chronic subtype B where the latter had mutational pathways significantly driven by N-glycosylation. Our study provides insights into the mutational pathways HIV takes to evade the immune response, and presents features more likely to establish founder infection, valuable for effective vaccine design.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Computational Biology
  • Glycosylation
  • HIV Envelope Protein gp160 / genetics*
  • HIV Envelope Protein gp160 / immunology
  • HIV Infections / genetics*
  • HIV Infections / immunology
  • HIV Infections / virology
  • HIV-1 / genetics*
  • HIV-1 / pathogenicity
  • Humans
  • Immune Evasion / genetics
  • Immunity / genetics
  • Immunity / immunology
  • Mutation / genetics
  • Protein Binding / genetics
  • env Gene Products, Human Immunodeficiency Virus / genetics*
  • env Gene Products, Human Immunodeficiency Virus / immunology

Substances

  • HIV Envelope Protein gp160
  • env Gene Products, Human Immunodeficiency Virus
  • gp160 protein, Human immunodeficiency virus 1

Associated data

  • Dryad/10.5061/dryad.r19c2

Grants and funding

This work was funded by an Australian Research Council Discovery grant (DP180103893), awarded to JMM. The Australian Research Council (arc.gov.au) had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.