BMP2 and HIV-1 infection: Systemic induction of TGF-β superfamily members was found to differ markedly from that of many other innate cytokines (including IFN-α), with a modest but extremely rapid increase in plasma TGF-β1 concentrations occurring as viremia first began to increase in acute HIV-1 infection that was then sustained throughout acute infection and into chronicity, whilst plasma concentrations of BMP-2 and activins A and B were largely unperturbed.