The transgenic carp were produced by micro-injection of CAgcGHc into the fertilized eggs. Observation of the thymus development between the transgenics and non- transgenic controls was carried out. The thymus of one-year- old transgenics F1 showed a great increase in both size and weight. The unilateral thymus of the transgenics weighed from 190 to 295 mg with average 218.6 mg, whereas the uni-lateral thymus of the controls weighed 20—81 mg with av-erage 42.5 mg; i.e. the thymus weight in the transgenics was 5.14 fold over that in the controls. The index of thymus/body weight in the transgenics was 2.97 fold over the controls. Light microscopy observation indicated that the thymus of the transgenics well developed with the thickened outer re-gion and compactly arranged thymocytes, while the thymus in the controls were degenerating with the thinned outer region, scattered thymocytes and groups of fatty cells. Fur-ther analysis with the electron microscopy revealed that pro-liferous cells in the transgenics were mainly small lympho-cytes and no pathological changes were found. The results confirmed that the 揂ll-fish?GH-transgene promotes thy-mus development and thymocyte proliferation, and retards thymus degeneration. The study has laid a foundation for further analysis of the immunobiological function in GH- transgenic carp.
Lectin binding patterns in the hemopoietic organs and blood cells of Grass carp ( Ctenopharyngodon idellus ), Chinese soft shelled turtle ( Trionyx sinensis) were observed with two affinity histochemical methods, ABC staining and fluorescence bound lectin staining. Concanavalin (ConA), Phytohemagglutinin (PHA), Pokeweed agglutinin (PWM) and Lipopolysaccharide (LPS) binding sites were distributed mainly on the plasma membrane of lymphocytes. ConA, PHA binding sites were distributed in thymus, cordic structure of head kidney and scatterly spleenic tissue of C. idellus, also in thymus and periellipsoidal lymphatic sheaths and marginal region of T. sinensis. PWM, LPS binding sites were scatterly distributed in cordic structure of head kidney of C. idellus, spleenic tissue of C. idellus and T. sinensis, but positive cell groups were not obvious. ConA, PHA and PWM positive percents of lymphocytes in blood smears were repectively 36%～41%, 33%～37%, 38%～43% in C. idellus and 37%～48%, 36%～45%, 44%～53% in T. sinensis, but percents of positive cells were repectively 15%～18%, 14%～17%, 9%～12% in imprints of head kidney of C. idellus.
