Flow cytometric analysis of proliferative responses of carp Cyprinus carpio peripheral blood leukocytes to mitogens and to the hemoflagellate Trypanoplasma borreli

摘要

The activation of carp peripheral blood leukocytes(PBL) was analysed radiometrically and by means of flow cytometry(FCM) in order to compare the results obtained with both methods. The qualitative and quantitative FCM analyses fo cellular morphololgy and viability resulted in a further characterisation of proliferative responses of carp PBL to Typanoplasma borreli in vivo and in vitro. The lymphocyte population of PBL from T. borreli-infected carp exhibited a marked shift in forward scattered light(FSC; cell size). When PBL from healthy carp were strimulated with mitogens in vitro, a lymphoid population with increased FSC profiles was also observed. The number of these cells coincided to ratios of ~3H-thymidine incorporation, recorded from corresponding cultrues. Thus, it was concluded that the increase in size of stimulated lymphocytes could be due to blastogenic transformation. The advantage of the FCM procedure is that activation and proliferation of carp lymphocytes can be monitored without labelling the cells. Cocultures of mitogen-stimulated carp PBL and T. borreli revealed the ability of the parasite to suppress lymphocyte proliferation in vitro.