I read the Groom paper and the Japanese study together.Groom is definitely trying to cast doubt about XMRV in PMBC becuse of the existence of specific restrictive factors therein.The Japanese study successfully transfected viruses into PMBcs and harvested virus at high titre.If these authors are both correct then XMRV spreads by something called cell cell transfer making it VERY hard to find
Fascinating post Gerwyn. Is this what they meant in the Science paper by "cell-associated transmission"? Maybe the virus "prefers" that?
"Cell culture experiments revealed that patient-derived XMRV is infectious and that both cell-associated and cell-free transmission of the virus are possible." - Lombardi et. al.