title: Thermal inactivation and gradient studies of the active agent in rheumatoid arthritis.
abstract: Ten day embryonated eggs have been used for testing supernatants of pooled RA synovial tissues for the presence of the RA-active agent. A high thermal resistance of the agent was observed up to 40 min of heating both at 100 and 121 degrees C with complete loss of infectivity only after 60 min at 121 degrees C. The high thermal resistance at 121 degrees C suggested that the active agent does not depend on a double-stranded DNA or RNA. It probably has no protein component and has a minimal number of subunits for replication. The CsC1 ultracentrifugation identified a concentration of high infectivity at densities in the range of 1.440-1.490 g/ml in five experiments.
mesh_terms: D000818:Animals; D001172:Arthritis, Rheumatoid / Q000382:microbiology* / Q000635:transmission; D002500:Centrifugation, Isopycnic; D002642:Chick Embryo; D002645:Chickens; D006358:Hot Temperature