antibodies were of the igg , igm , and ( infrequently ) iga classes and were either specific for a single species ( as defined by a difference in titer of fourfold or more ) or reacted with common legionella antigens ( 30 [ 45 % ] vs. 36 [ 55 % ] of 66 seroconversions , respectively ) .
C0003241
antibodies
C2825347
iga