If you looked at the antibodies that were present in the blood, for example, you would find that most of those antibodies are IgM during this initial period of antibody concentration rise.

如果你现在观察血液中存在的抗体,举个例子,在初次免疫的抗体浓度上升阶段,你将会发现大部分的抗体都是IgM

耶鲁公开课 - 生物医学工程探索课程节选