HIV and ID Observations

First, who was Berlin Patient I?

Second, over in the journal Blood is the latest update on Berlin Patient II, the guy apparently cured of HIV by bone marrow transplantation:

We have previously reported the case of an HIV-infected patient in whom viral replication remained absent despite discontinuation of antiretroviral therapy after transplantation with CCR5Δ32/Δ32 stem cells…  In the present study, we demonstrate successful reconstitution of CD4+ T cells at the systemic level as well as in the gut mucosal immune system following CCR5Δ32/Δ32 stem cell transplantation, while the patient remains without any sign of HIV infection… In conclusion, our results strongly suggest that cure of HIV has been achieved in this patient.

Ever since this was first presented as a poster at CROI in 2008, it was pretty clear that this was a special case, and I’ve written about it several times before — first time here.

What’s different now, of course, is that the longer duration of follow-up has allowed the authors to give much more detailed information about both his virologic and immunologic status — and to make more confident statements that he is in fact cured of HIV.

And I agree.

But numerous questions about this fascinating case remain, including the biggie — how did this happen? Was it the CCR5-negative status of the donor’s cells?  Something about the “conditioning” (there’s a euphemism for you) regimen?  The fact that he’d been virologically suppressed when he went into the transplant?  (It’s obviously not just this.)  Some combination of the above?

And though of course this transplant strategy can’t be widely adopted, one would expect at least one other similar case to surface soon, right?

By the way, for HIV history trivia buffs, this guy was Berlin Patient I.  Must be something in the water.