An examination of signs of disease progression in survivors of the Sydney Blood Bank Cohort (SBBC).
BACKGROUND
The Sydney Blood Bank Cohort (SBBC) was infected between 1981 and 1984 with a nef/LTR defective strain of HIV-1. Different responses to HIV-1 infection have emerged between cohort members in the last 5 years. Three recipients (C135, C64 and C49) remain asymptomatic, have normal CD4 T cell counts, below detection (BD) viral loads (VL), remain therapy naive and are termed long-term non-progressors (LTNP). The donor (D36) and the two recipients (C98 and C54) have significantly declining CD4 T cell counts, detectable VL and are now long-term survivors (LTS). In contrast, in the SA cohort, comparison study group for the SBBC, five of 24 remain therapy naïve after 15 years infection with HIV-1 and all have detectable VL.


OBJECTIVE
This paper examines different outcomes to long-term infection with HIV-1 in the SBBC and provides a brief overview of the therapy naïve in a comparison study group, the SA cohort.


METHODS
Retrospective epidemiological follow-up of the SBBC and the SA cohort has been conducted for >15 years. Analysis of CD4 T cell counts, VL and intermittent monitoring of HIV-specific proliferative responses are reviewed. Viral sequence changes in the SBBC will be considered.


RESULTS
Prior to therapy D36 had a CD4 T cell count of 160/mm(3) and plasma VL of 9900 copies/ml while C98 had a CD4 T cell count of 387/mm(3) and plasma VL of 11491 copies/ml. After 1 month of therapy, plasma VL was BD (<400 copies/ml) and both showed significant increase in CD4 T cell counts. Molecular changes have occurred in D36 and C98 viral strains, the most recently evolved quasispecies have larger deletions in the nef/LTR region.


CONCLUSIONS
Infection with nef/LTR deleted HIV-1 has resulted in slower disease progression for the SBBC. The three LTNP have maintained normal low levels of activated CD8 T cells and strong HIV-specific proliferative responses to HIV-1 p24, which are associated with control of viral replication.
Birch
M R
MR
HIV Epidemiology Research Unit (HERU), Australian Red Cross Blood Service-NSW (ARCBS-NSW), Level 3/131 Clarence Street, Sydney, NSW 2000, Australia. mbirch@arcbs.redcross.org.au
Learmont
J C
JC
Dyer
W B
WB
Deacon
N J
NJ
Zaunders
J J
JJ
Saksena
N
N
Cunningham
A L
AL
Mills
J
J
Sullivan
J S
JS
D001315:Australia / Q000453:epidemiology; D001782:Blood Donors; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D017353:Gene Deletion; D015754:Genes, nef; D015658:HIV Infections / Q000453:epidemiology / Q000635:transmission / Q000821:virology*; D016325:HIV Long Terminal Repeat; D020276:HIV Long-Term Survivors / Q000706:statistics & numerical data; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012189:Retrospective Studies; D019562:Viral Load