Polypeptide Profiles of Chlamydia pneumoniae Strains Isolated from Japan and Western Blot Analysis Using Patients' Sera

Polypeptide profiles were compared among Chlamydia pneumoniae strain of AC-43, which wasisolated from a Japanese child, and other strains of C. pneumoniae. There was no distinctive differences among these strains. All strains showed marked band on 39.5KDa area, which is equivalent with the major outer membrane protein (MOMP). Patients infected with C. pneumoniae were analyzed by Western blot using AC-43. Reaction for 98, 68, 60 KDa proteins were recognized among sera which showed positive results for anti-C. pneumoniaeIg G antibody. There were two family members from whom C. pneumoniae was not isolated and anti-C.pneumoniae Ig G antibody was negative. Sera obtained from them also showed weak reaction on 98KDa protein area. Strong reaction on MOMP area was demonstrated in one patient from whom C.pneumoniae was isolated. Monoclonal antibody produced from AC-43 strain showed no reactionagainst homologous antigen. Reaction to 98 KDa protein was detected in all of the patients infected with C. pneumoniae.However, recognition to MOMP of C. pneumoniae seems to be different among patients. This resultmight suggest the presence of subtype among C. pneumoniae strains.