Mycoplasma pneumoniae lacks immunologically-active eukaryotic actin-like antigens.

Mycoplasma pneumoniae was tested for immunologically active eukaryotic actin-like antigens with the use of both polyclonal and monoclonal anti-actin antibodies. No reactivity was demonstrable. Monoclonal antibody OC2F5, which reacts with a M. pneumoniae antigen that co-migrates with actin in one-dimensional sodium dodecyl sulphate polyacrylamide electrophoresis, did not recognize actin. Organism-specific actin antigens are not likely to be responsible for the development of smooth muscle antibodies during acute M. pneumoniae infection.