BALB/c mice are more susceptible to P.carinii than the C57BL/6 mice by natural transmission, and all the immunocompetent mice can clear the infection of P.carinii by cellular and humoral immune responses.

• BAL B/ c和 C5 7BL / 6小鼠感染 P.；c后5 wk可产生有效的细胞和体液免疫反应并清除肺内感染的 P