Last year Steven Yukl from UCSF presented the results of an exhaustive
search for HIV genetic material in Timothy Brown (aka the Berlin Patient) -- the
one adult individual considered cured of the infection. The study engendered
controversy, because a few of the multiple independent laboratories that
participated did obtain positive readings for trace amounts of HIV RNA and DNA
in some blood and tissue samples (the vast majority of the tests, including
those looking for replication-competent virus in large volumes of cells, were
negative). One scientist in particular, who was not involved in the research, made wild-eyed claims -- via press release,
no less -- that the findings meant that Brown was either not really cured or
potentially had been re-infected. The results of the study were published
yesterday in the open access journal PLoS Pathogens, and the authors offer a
sober discussion of their implications. In particular, they highlight the
difficulty of formally proving a cure using current virologic assays that are operating
at the limits of their sensitivity. Rather, they suggest, the waning of immune
responses to HIV in Timothy Brown (both antibodies and T cells) may represent the
clearest confirmation that he is indeed cured.
In the staid language of the methods section, the published
paper also offers insight into the extent of Timothy Brown's selfless
commitment to contributing to HIV cure research:
"The subject was enrolled in the UCSF-based SCOPE cohort and
had multiple study visits over two years. Plasma, serum, and PBMC were obtained
at each visit. The subject also consented to separate procedures at UCSF,
including leukapheresis, lumbar puncture, and flexible sigmoidoscopy with
rectal biopsies. He was also seen at the University of Minnesota, where he underwent
a lymph node biopsy and a colonoscopy with ileal and rectal biopsies."
Any one of these procedures might well prompt trepidation in
most people even if they were medically indicated; to volunteer to undergo them
for the purposes of research is extraordinarily laudable.
Richard Jefferys is the coordinator of the Michael Palm HIV Basic Science, Vaccines & Prevention Project Weblog at the Treatment Action Group (TAG). The original blog post may be viewed here.