Haematopoietic clonal succession in normal and bone marrow transfused mice
نویسندگان
چکیده
Culture of lymphocytes from adult Xenopus laevis (Daudin) (a pipid anuran amphibian) with mitogens (PHA, ConA, LPS and PWM) reveals a wide variation in the mitogen sensitivity of these cells: relatively high concentrations of mitogen are required to stimulate Xenopus lymphocytes compared with the concentrations appropriate for mammalian lymphocytes. Significantly better responses are obtained using spleen cells from 'young' adult (metamorphosed) Xenopus aged 6-10 months from 'mature', 4-5 year-old Xenopus. There is evidence for a population of suppressor cells, probably with functional T lymphocyte characteristics, in the spleens of 'mature' Xenopus: mitogen responsiveness of 'young' splenocytes is depressed when 'mature' splenocytes are included in 72 h cultures; non-nylon wool adherent cells from 'mature' Xenopus spleens exert a similar suppressive effect. A supernatant factor prepared from cultured, 'mature' spleen cells may mediate such suppression. In unidirectional mixed lymphocyte reactions using 'young' and 'mature' spleen cells, poor stimulation is obtained when 'mature' cells are used as responders, but good stimulation is obtained with 'young' responders. Our data suggest that there is considerable post-metamorphosis maturation of the cell-mediated arm of the immune response in Xenopus laevis.
منابع مشابه
Haematopoietic clonal succession in normal and bone marrow transfused mice
Culture of lymphocytes from adult Xenopus laevis (Daudin) (a pipid anuran amphibian) with mitogens (PHA, ConA, LPS and PWM) reveals a wide variation in the mitogen sensitivity of these cells: relatively high concentrations of mitogen are required to stimulate Xenopus lymphocytes compared with the concentrations appropriate for mammalian lymphocytes. Significantly better responses are obtained u...
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