Cytomegalovirus rather than HIV triggers the outgrowth of effector CD8+CD45RA+CD27- T cells in HIV-1-infected children
Bekker, V.; Bronke, C.; Scherpbier, H.ët.J.; Weel, J.F.; Jurriaans, S.; Wertheim-van Dillen, P.M.E.; van Leth, F.; Lange, J.M.A.; Tesselaar, K.; van Baarle, D.; Kuijpers, T.W.
Aids 19(10): 1025-1034
2005
ISSN/ISBN: 0269-9370 PMID: 15958833 DOI: 10.1097/01.aids.0000174448.25132.adDocument Number: 265174
To analyse the effect of viral coinfections on immune reconstitution in HIV-1-infected children (< 18 years) taking highly active antiretroviral therapy (HAART). Absolute lymphocyte numbers of various subsets of CD8 T cells were measured. Prior cytomegalovirus (CMV) infection correlated with an increased number of CD8 effector T cells (i.e., CD45RA+CD27-) at baseline (CMV-seropositive versus CMV-seronegative patients; P = 0.009), as well as an increased state of T cell activation as defined by HLA-DR and CD38 expression. The expansion of effector CD8 T cells persisted over time, independent of the HIV response to HAART. Numbers of CD8 effector T cells were significantly higher in patients with CMV replication as reflected by persistent urinary CMV shedding and periodic CMV DNAaemia (P = 0.02). These patients also showed an increase in CMV-specific antibodies compared with those without CMV shedding (P = 0.007). The number of CMV-specific interferon-gamma (IFN-gamma)-producing CD8 T cells was lower in children who persistently shed CMV compared with those who did not (P = 0.02). In contrast, CMV-specific CD4 T cell responses were detected at similar levels in both groups. In HIV-1-infected children, CMV infection correlated with the outgrowth of CD8+CD45RA+CD27- effector T cells. Activation of the immune system by persistent CMV secretion resulted in increasing CMV-specific IgG and higher numbers of CD8 effector T cells. Despite these increases, the CMV-specific IFN-gamma-producing CD8 T cell response was diminished, which could explain the inability to suppress CMV completely in 41% of HIV-1-infected children.