IDENTIFICATION OF CANDIDA-ALBICANS CELL-WALL ANTIGENS LOST DURING SUBCULTURE IN SYNTHETIC MEDIA

A high variability in reactivity was observed when Candida albicans st rains freshly isolated from both patients with candidiasis and asympto matic carriers were tested against different human sera. The highest r eactivity was observed in C. albicans strains isolated from blood cult ures. This high reactivity was observed when the isolates were tested against sera from patients with Candida oesophagitis. patients with vu lvovaginal candidiasis, or asymptomatic carriers but not against sera from blood donors. The antigenic reactivity of the strongly reactive s trains, but not that of the weakly reactive strains, decreased during subculture in synthetic media. Five major components of an apparent mo lecular mass of > 200, 67-70, 49-52, 33-35 and 29-31 kDa were observed in alpha-mannosidase extracts from C. albicans strains from both bloo d cultures (Group I) and patients with Candida oesophagitis (Group II) subcultured in synthetic media for different times. Changes in staini ng intensity through the different subcultures were observed for some bands. Group I strains showed a decrease in staining intensity for ban ds of > 200 and 67-70 kDa, an increase for bands of 33-35 and 29-31 kD a, but no changes were observed for the band of 49-52 kDa. Group II st rains showed opposite changes in banding intensity. A decrease in stai ning intensity was observed for the proteins of 33-35 and 29-31 kDa, a n increase for the protein of 49-52 kDa, and no change in intensity wa s observed for the band of 67-70 kDa. A component of > 200 kDa showed an irregular expression through the subcultures. The main antigen pres ent in extracts from the first subculture of isolates from Group I and II had a molecular mass of 67-70 kDa. It could be related to the P an tigens since it disappeared following subculture of the strains in syn thetic media.