[Effect of a soluble Jagged 1/Fc chimera protein on the activation, proliferation and cell cycle of lymphocytes in mice]

Abstract

Aim: To investigate effect of a soluble Jagged 1/Fc chimera protein (Jagged 1/Fc) on activation, proliferation and cell cycles of lymphocytes in BALB/c mice.

Methods: A model to evaluate the lymphocyte proliferation stimulated with a polyclonal activator, concanavalin A (ConA), was established by a carboxy-fluorescein diacetate-succinimidyl ester (CFDA-SE)-labeling technique. Under an effective dose of 500 mug/L of Jagged 1/Fc, the effect of it on the lymphocyte proliferation was analyzed by flow cytometry. A propidium iodide-labeling technique was applied to estimate the influence of Jagged 1/Fc on the lymphocyte cell-cycle stimulated by phorbol 12,13-dibutyrate (PDB) plus Ionomycin (Ion). Expression levels of CD69 and CD25 molecules on surface of CD3(+) lymphocytes activated with ConA in the presence of Jagged 1/Fc were observed by a fluorescein-conjugated monoclonal antibody-labeling technique.

Results: Jagged 1/Fc had no effect on the expression levels of CD69 and CD25 of the CD3(+) lymphocytes stimulated with or without ConA, and no effect on the proliferation index of the lymphocytes stimulated by ConA or PDB plus Ion. It led to the increase of sub-G0 phase cell proportion and the decrease of S phase cell proportion of the lymphocytes, but did not influence the changes of the lymphocyte cell-cycle induced by PDB plus Ion.

Conclusion: The results suggest that Jagged 1/Fc has no obvious effect on the activation and proliferation of lymphocytes in mice, but may promote the apoptosis of them, cause the G0/G1 phase arrest and block the S phase entry.