LYMPHOCYTE-PROLIFERATION IN RESPONSE TO BRUCELLA-ABORTUS RB51 AND 2308 PROTEINS IN RB51-VACCINATED OR 2308-INFECTED CATTLE

Cattle vaccinated with Brucella abortus strain RB51 (SRB51) or infecte d with strain 2308 (S2308) had lymph node lymphocytes which proliferat ed most when incubated with 32-, 27-, 18-, or <18-kDa proteins of eith er SRB51 or S2308. Some S2308-infected cattle but no SRB51-vaccinated cattle had lymphocytes which proliferated in response to 80- and 49-kD a proteins of SRB51 and S2308, These results suggest that cattle vacci nated with SRB51 or infected with S2308 have lymphocytes which prolife rate in response to most of the same S2308 proteins and that the immun odominant protein antigens of SRB51 and S2308 have similar molecular m asses of 32, 27, 18, and <18 kDa.