An experimental ME/CFS treatment in Norway involves some tantalizing clues: B cell depletion with Rituximab. The study was initiated after a patient with CFS had unexpected, marked recovery of CFS symptoms following cytotoxic chemotherapy for Hodgkins's disease. A following study was initiated recruiting patients, for B-Cell depletion therapy, all patients in the study demonstrated substantial improvement after the first infusion, followed by a relapse, improvement following the second infusion, and an even more marked improvement after the third infusion. This treatment will not likely gain a mainstay in ME/CFS treatment, as it poses a high degree of risk, costs over $10,000 a treatment, and would require infusions on an ongoing basis.
Nevertheless, it shows that B-Cells beyond a reasonable doubt play a major role in the pathogenesis of ME/CFS. By depleting XMRV infected B cells, it can be seen that healthy B cells develop from progenitor stem cells, but soon succumb to infection - indicating that XMRV infects other classes of lymphocytes. It leaves room to infer that antiretroviral therapy would have an even more profound and lasting effect: Most T-cells, with the exception of memory cells have an average lifespan of about 8 weeks. After a couple month course of antiretroviral therapy, it would not be unreasonable to see the vast majority of lymphocytes replaced by healthy cells
Fluge and Mella BMC Neurology 2009 9:28 doi:10.1186/1471-2377-9-28