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AIDS
Research Alliance of America collaborative effort bears fruit—
Mucosal biopsy study results presented in Chicago
AIDS
Research Alliance of America has been collaborating with Dr.
Peter Anton and colleagues at UCLA, USC, and Cell Genesys,
Inc., on a study to clinically validate a method of detecting
and quantifying HIV in tissue biopsy specimens taken from
HIV-infected individuals. The following abstract has resulted
from this work. It was accepted for presentation at the 6th
Conference on Retroviruses and Opportunistic Infections in
Chicago, IL in poster form.
HIV-1
is Detectable in Mucosal Biopsies in Patients with Undetectable
Plasma Viral Loads
M. Poles*1, J. Elliott1, S. Brown4, D-P. Shi1, S. Chiong2,
K. Hege3, I. McGowan4, H. Lenz2, I. Chen1, P. Anton1. 1UCLA
AIDS Institute, UCLA School of Medicine, Los Angeles CA, 2USC
School of Medicine, Los Angeles CA, 3Cell Genesys Inc., Foster
City CA, 4AIDS Research Alliance, Los Angeles
Gut
mucosal biopsies from 17 HIV (+) patients with undetectable
plasma viral loads were assessed for HIV RNA to determine
if virus can be detected and quantified in this lymphoid site
when plasma levels cannot be used as a clinical index. This
abstract reports the baseline observations of a year-long
study.
Methods: 17 subjects, HIV(+) for >3 years on HAART
and having undetectable plasma HIV-1 RNA viral load (NASBA:
<400 copies/ml) were evaluated (mean CD4 count: 474.7 cells
(range 15-1100 SD=316.7)). RNA was extracted from a single
rectosigmoid biopsy (mean weight: 10mg, average yield = 25
mg/biopsy). HIV RNA was quantified using HIV LTR-specific
primers by RT-PCR (assay sensitivity = 10 copies). Total RNA
recovery is >95%.
Results:
15 of 17 patients with undetectable plasma viral load (88%)
had detectable HIV in a single mucosal biopsy. Identical results
occurred when a 2nd biopsy from the same site and same time
was analyzed. Assay variation of the same extracted RNA run
120 days apart was <0.2 log; intra-subject variation between
the 2 biopsies was <0.3 log. In biopsies from these 15 patients
the mean number of copies of HIV-1 LTR per mg of total RNA
was 215.8 (range 44-768 SD=190.2). There was no correlation
between the CD4 cell count and mucosal viral load (r = -0.1146).
2 subjects with undetectable plasma viral HIV RNA also had
no detectable mucosal viral load (blood CD4 cell counts of
130 and 550).
Conclusions:
HIV RNA is detectable in the mucosa of patients with undetectable
plasma viral load. Mucosal HIV quantification may represent
an important clinical tool in evaluating treatment efficacies
and compartmental factors in patients with undetectable plasma
viral loads.
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