Induction of robust cellular and humoral virus-specific adaptive immune responses in human immunodeficiency virus-infected humanized BLT mice

J Virol. 2009 Jul;83(14):7305-21. doi: 10.1128/JVI.02207-08. Epub 2009 May 6.

Abstract

The generation of humanized BLT mice by the cotransplantation of human fetal thymus and liver tissues and CD34(+) fetal liver cells into nonobese diabetic/severe combined immunodeficiency mice allows for the long-term reconstitution of a functional human immune system, with human T cells, B cells, dendritic cells, and monocytes/macrophages repopulating mouse tissues. Here, we show that humanized BLT mice sustained high-level disseminated human immunodeficiency virus (HIV) infection, resulting in CD4(+) T-cell depletion and generalized immune activation. Following infection, HIV-specific humoral responses were present in all mice by 3 months, and HIV-specific CD4(+) and CD8(+) T-cell responses were detected in the majority of mice tested after 9 weeks of infection. Despite robust HIV-specific responses, however, viral loads remained elevated in infected BLT mice, raising the possibility that these responses are dysfunctional. The increased T-cell expression of the negative costimulator PD-1 recently has been postulated to contribute to T-cell dysfunction in chronic HIV infection. As seen in human infection, both CD4(+) and CD8(+) T cells demonstrated increased PD-1 expression in HIV-infected BLT mice, and PD-1 levels in these cells correlated positively with viral load and inversely with CD4(+) cell levels. The ability of humanized BLT mice to generate both cellular and humoral immune responses to HIV will allow the further investigation of human HIV-specific immune responses in vivo and suggests that these mice are able to provide a platform to assess candidate HIV vaccines and other immunotherapeutic strategies.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antibody Formation*
  • Antigens, Surface / genetics
  • Antigens, Surface / immunology
  • Apoptosis Regulatory Proteins / genetics
  • Apoptosis Regulatory Proteins / immunology
  • B-Lymphocytes / immunology
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Dendritic Cells / immunology
  • Disease Models, Animal*
  • HIV / immunology*
  • HIV Antibodies / blood
  • HIV Infections / genetics
  • HIV Infections / immunology*
  • HIV Infections / virology
  • Humans
  • Immunity, Cellular
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID
  • Oligonucleotide Array Sequence Analysis
  • Programmed Cell Death 1 Receptor

Substances

  • Antigens, Surface
  • Apoptosis Regulatory Proteins
  • HIV Antibodies
  • Pdcd1 protein, mouse
  • Programmed Cell Death 1 Receptor