A novel mechanism of CD4 lymphocyte depletion involves effects of HIV on resting lymphocytes: induction of lymph node homing and apoptosis upon secondary signaling through homing receptors
- PMID: 9886395
A novel mechanism of CD4 lymphocyte depletion involves effects of HIV on resting lymphocytes: induction of lymph node homing and apoptosis upon secondary signaling through homing receptors
Abstract
Recently, we reported that abortive HIV infection of resting human T lymphocytes up-regulated expression of CD62L, the receptor for homing to lymph nodes (LNs), and enhanced homing of these cells from the blood into the LNs (Wang et al., 1997, Virology 228:141). This suggested that HIV-induced homing of resting lymphocytes (which comprise >98% of all lymphocytes) may be a major mechanism for the reduction of CD4+ lymphocytes in the blood of infected individuals. This mechanism also could be partially responsible for the lymphadenopathy that often develops at the same time that CD4+ lymphocytes are disappearing from the blood. In this study, we show that secondary signaling through the homing receptors (CD62L, CD44, CD11a) of abortively infected resting CD4+ T lymphocytes induced apoptosis. These signals would occur as the cells home into the LNs. Apoptosis did not occur after secondary signaling through some other receptors (CD26, CD4, CD45, and HLA class I) or in HIV-exposed resting CD8+ lymphocytes signaled through the homing receptors. These findings indicate that HIV-induced homing of resting CD4+ lymphocytes to LNs results in death of many of these cells. This was confirmed in the LNs of SCID mice that were i.v. injected with HIV-exposed resting human lymphocytes. Thus, these effects of HIV upon binding to resting CD4+ T lymphocytes, which are not permissive for HIV replication, may significantly contribute to their depletion in vivo. These findings also offer an explanation for the bystander effect observed in the LNs of AIDS patients, whereby cells not making virus are dying.
Similar articles
-
HIV induces homing of resting T lymphocytes to lymph nodes.Virology. 1997 Feb 17;228(2):141-52. doi: 10.1006/viro.1996.8397. Virology. 1997. PMID: 9123820
-
Apoptosis induced in HIV-1-exposed, resting CD4+ T cells subsequent to signaling through homing receptors is Fas/Fas ligand-mediated.J Leukoc Biol. 2007 Jan;81(1):297-305. doi: 10.1189/jlb.0506338. Epub 2006 Oct 20. J Leukoc Biol. 2007. PMID: 17056762
-
Markers of lymphocyte homing distinguish CD4 T cell subsets that turn over in response to HIV-1 infection in humans.J Immunol. 1999 Sep 15;163(6):3539-48. J Immunol. 1999. PMID: 10477629
-
Are blockers of gp120/CD4 interaction effective inhibitors of HIV-1 immunopathogenesis?AIDS Rev. 2006 Jan-Mar;8(1):3-8. AIDS Rev. 2006. PMID: 16736946 Review.
-
Could Nef and Vpr proteins contribute to disease progression by promoting depletion of bystander cells and prolonged survival of HIV-infected cells?Biochem Biophys Res Commun. 2000 Jan 27;267(3):677-85. doi: 10.1006/bbrc.1999.1708. Biochem Biophys Res Commun. 2000. PMID: 10673351 Review.
Cited by
-
HIV Replication in Humanized IL-3/GM-CSF-Transgenic NOG Mice.Pathogens. 2019 Mar 12;8(1):33. doi: 10.3390/pathogens8010033. Pathogens. 2019. PMID: 30871027 Free PMC article.
-
Modeling of HIV-1 infection: insights to the role of monocytes/macrophages, latently infected T4 cells, and HAART regimes.PLoS One. 2012;7(9):e46026. doi: 10.1371/journal.pone.0046026. Epub 2012 Sep 26. PLoS One. 2012. PMID: 23049927 Free PMC article.
-
Thirty Years with HIV Infection-Nonprogression Is Still Puzzling: Lessons to Be Learned from Controllers and Long-Term Nonprogressors.AIDS Res Treat. 2012;2012:161584. doi: 10.1155/2012/161584. Epub 2012 May 27. AIDS Res Treat. 2012. PMID: 22693657 Free PMC article.
-
Incomplete immune recovery in HIV infection: mechanisms, relevance for clinical care, and possible solutions.Clin Dev Immunol. 2012;2012:670957. doi: 10.1155/2012/670957. Epub 2012 Mar 14. Clin Dev Immunol. 2012. PMID: 22474480 Free PMC article. Review.
-
Mechanisms of HIV-associated lymphocyte apoptosis: 2010.Cell Death Dis. 2010 Nov 11;1(11):e99. doi: 10.1038/cddis.2010.77. Cell Death Dis. 2010. PMID: 21368875 Free PMC article. Review.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Research Materials
Miscellaneous