LYME-DISEASE IN HUMAN DR4DW4-TRANSGENIC MICE

The evolution of Lyme arthritis in DR4-transgenic mice infected with B orrelia burgdorferi was studied because chronic Lyme arthritis in huma ns is associated with an increased frequency of the HLA-DR4 allele. B1 0 nontransgenic and DR4-transgenic mice expressing chimeric human-mous e major histocompatibility complex class II genes in which the human a lpha 1 and beta 1 domains of DR4Dw4 replaced the corresponding domains of the mouse I-E(d) were inoculated with B. burgdorferi and examined at up to 180 days for infection and disease. All mice were infected th roughout the 180 days, and arthritis evolved to equal severity in tran sgenic and control mice within 30 days and resolved by day 120. Both g roups of mice developed high antibody titers to B. burgdorferi, but an tibodies to outer surface proteins A and B were not readily detectable . The DR4Dw4 transgene did not predispose mice to the development of c hronic Lyme arthritis.