1999: Gary Wormser reports that OspA is immunosuppressive.
In his 1999 study (published in 2000) "Modulation of lymphocyte proliferative responses by a canine Lyme disease vaccine of recombinant outer surface protein A (OspA)," he’s talking about how OspA causes immunosuppression in dogs too. The dog vaccines only tolerize against arthritis; they do not prevent spirochetes.
"The effect of the recombinant OspA dog vaccine preparation on human lymphocyte proliferative responses was investigated. Cultures of mitogen- or antigen-stimulated normal human PBL were supplemented with the OspA vaccine preparation at various concentrations. Fig. 1A reveals a dose-dependent regulatory effect of OspA on the proliferation of ConA-stimulated PBL, as compared to controls using saline in place of OspA or unsupplemented PBL cultures. An approximately 25-35% reduction of proliferation was observed with the OspA preparation supplemented at 0.1% volume, while a maximum reduction of 50-60% (P T 0.01) was observed with supplementation at 7% or more (Fig. 1B).