Expression of proteins in mouse thymocytes induced by low dose X-rays and their biological activity / 中国病理生理杂志

ABSTRACT

AIM: To observe the expression of proteins induced by whole-body irradiation in mice with low dose X-rays and their biological activity. METHODS: To analyse the expression of protein induced by whole-body irradiation with 75mGy X-rays and sham-irradiation, the method of gel filtration with Sephadex G-100 and HPLC were used. The biological activity of protein expressed in thymocytes was observed by mouse splenocyte proliferation and chromosome aberration of human peripheral blood lymphocytes. RESULTS: HPLC analysis showed that there was a marked decrease in expression of 24.5 kD protein molecule in the fractions of thymocyte extract in comparison with the corresponding fractions from the sham-irradiated control mice. These protein fractions from the thymocytes of the irradiated mice at the concentration of 6.25 mg/L showed both inhibitory effect on normal T cell proliferation and protective effect on the chromosome damage induced by high dose radiation. CONCLUSION: Down regulation of 24.5 kD protein molecule expression may have implications in the mechanism of immunoenhancement and cytogenetic adaptive response induced by low dose radiation.