Influence of human T cell lymphotropic virus type 2 coinfection on virological and immunological parameters in HIV type 1-infected patients.
BACKGROUND
Human T cell lymphotropic virus type 2 (HTLV-2) infection is not rare among injection drug users with human immunodeficiency virus (HIV) infection and may exert a protective role in the progression of HIV disease.


METHODS
Immunological and virological parameters were compared in HIV-HTLV-2-coinfected patients and a control group of HIV-monoinfected subjects. All individuals were antiretroviral therapy naive. HIV-specific CD8+ T cell levels were measured using an interferon-gamma assay in response to 125 optimally defined HIV peptides divided into 5 pools. Immune activation was evaluated by measuring levels of CD38 in different CD4+ and CD8+ T cell subsets. In a subgroup of patients, the production of CCL4 in parallel with interferon-gamma was assessed in response to Gag peptides.


RESULTS
Lower plasma HIV-RNA levels were found in HIV-HTLV-2-coinfected patients than in HIV-monoinfected patients, despite the 2 groups having similar CD4+ T cell counts. Coinfected patients also had significantly lower levels of CD38 expression in total CD8+ T cells and in its naive subset. CD8+ T cell levels specific for each pool of peptides were similar in both groups, but cells mainly contributing to HIV Gag-specific responses in coinfected patients were CCL4 positive and interferon-gamma negative, whereas for HIV-monoinfected subjects, the response was dominated by CCL4-positive and interferon-gamma-positive cells.


CONCLUSIONS
HTLV-2 coinfection may exert a protective role on HIV disease progression by lowering HIV replication and immune activation. A predominance of CCL4 single positive HIV-specific CD8+ T cells in HIV-HTLV-2-coinfected patients could explain this effect.
Bassani
Sylvina
S
Service of Infectious Diseases, Hospital Carlos III, Madrid, 28029, Spain.
López
Mariola
M
Toro
Carlos
C
Jiménez
Victoria
V
Sempere
José M
JM
Soriano
Vincent
V
Benito
Jose M
JM
D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D054407:Chemokine CCL4; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000276:immunology* / Q000821:virology*; D015497:HIV-1 / Q000276:immunology / Q000472:pathogenicity* / Q000502:physiology; D015491:HTLV-II Infections / Q000150:complications*; D015367:Human T-lymphotropic virus 2 / Q000472:pathogenicity / Q000502:physiology; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis*; D008213:Lymphocyte Activation; D019402:Macrophage Inflammatory Proteins / Q000378:metabolism*; D008297:Male; D012367:RNA, Viral / Q000097:blood; D013601:T-Lymphocytes / Q000276:immunology; D014779:Virus Replication
D054407:Chemokine CCL4; D019402:Macrophage Inflammatory Proteins; D012367:RNA, Viral; D007371:Interferon-gamma