HIV-1/HSV-2 co-infected adults in early HIV-1 infection have elevated CD4+ T cell counts.
BACKGROUND
HIV-1 is often acquired in the presence of pre-existing co-infections, such as Herpes Simplex Virus 2 (HSV-2). We examined the impact of HSV-2 status at the time of HIV-1 acquisition for its impact on subsequent clinical course, and total CD4+ T cell phenotypes.


METHODS
We assessed the relationship of HSV-1/HSV-2 co-infection status on CD4+ T cell counts and HIV-1 RNA levels over time prior in a cohort of 186 treatment naïve adults identified during early HIV-1 infection. We assessed the activation and differentiation state of total CD4+ T cells at study entry by HSV-2 status.


RESULTS
Of 186 recently HIV-1 infected persons, 101 (54%) were sero-positive for HSV-2. There was no difference in initial CD8+ T cell count, or differences between the groups for age, gender, or race based on HSV-2 status. Persons with HIV-1/HSV-2 co-infection sustained higher CD4+ T cell counts over time (+69 cells/ul greater (SD = 33.7, p = 0.04) than those with HIV-1 infection alone (Figure 1), after adjustment for HIV-1 RNA levels (-57 cells per 1 log(10) higher HIV-1 RNA, p<0.0001). We did not observe a relationship between HSV-2 infection status with plasma HIV-1 RNA levels over time. HSV-2 acquisition after HIV-1 acquisition had no impact on CD4+ count or viral load. We did not detect differences in CD4+ T cell activation or differentiation state by HSV-2+ status.


CONCLUSIONS
We observed no effect of HSV-2 status on viral load. However, we did observe that treatment naïve, recently HIV-1 infected adults co-infected with HSV-2+ at the time of HIV-1 acquisition had higher CD4+ T cell counts over time. If verified in other cohorts, this result poses a striking paradox, and its public health implications are not immediately clear.
Barbour
Jason D
JD
HIV/AIDS Division, San Francisco General Hospital, University of California San Francisco, San Francisco, California, United States of America.
Sauer
Mariana M
MM
Sharp
Elizabeth R
ER
Garrison
Keith E
KE
Long
Brian R
BR
Tomiyama
Helena
H
Bassichetto
Katia C
KC
Oliveira
Solange M
SM
Abbate
Maria C
MC
Nixon
Douglas F
DF
Kallas
Esper G
EG
D000328:Adult; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000150:complications* / Q000378:metabolism*; D015497:HIV-1 / Q000378:metabolism*; D006561:Herpes Simplex / Q000097:blood* / Q000150:complications*; D018258:Herpesvirus 2, Human / Q000378:metabolism*; D006801:Humans; D007249:Inflammation; D008297:Male; D008954:Models, Biological; D010641:Phenotype; D012367:RNA, Viral / Q000378:metabolism; D019562:Viral Load
D012367:RNA, Viral