小牛胸腺细胞抑裂素对致分裂原(PHA或ConA)、可溶性抗原(破伤风类毒素),同种淋巴细胞体外刺激的人类淋巴细胞反应具有明显的抑制效应,而小牛血清则无此效应。其抑制百分比在浓度为100μg/0.5ml培养液时达90％以上。抑裂素剂量与抑制效应有关,浓度在25μg/0.5ml以下时不明显,剂量增高则加强。 Calf thymocyte inhibitory effect on mitogen (PHA or ConA), soluble antigen (tetanus toxoid), and lymphocyte stimulation of human lymphocytes stimulated in vitro by the same kind of lymphocytes, but calf serum does not have this effect effect. The percentage of inhibition was more than 90% at a concentration of 100 μg/0.5 ml culture solution. Inhibitory factor dose was related to inhibitory effect. The concentration was not obvious when the concentration was below 25 μg/0.5 ml, and the dose increased.