Changes in the plasma membrane surface of lymphocytes stimulated in vivo with DNCB

Summary Stereological principles have been used to evaluate ultrastructural changes which accompany the transformation of lymphocytes stimulated in vivo with dinitrochlorobenzene (DNCB). Whereas unstimulated lymphocytes and blast cells have slightly more than the minimal containing plasmalemmal surface for their volume, stimulated (blast-derived) lymphocytes have an excess surface area in the order of 30%. This observation is discussed in the context of altered cell function and the biosynthesis of additional membrane components.We wish to thank Prof. R. Barer for his continued support and encouragement. The work was undertaken by M.M. A.-H. in part fulfilment of requirements for the degree of Ph. D. in this department. M.M. A-H. was supported by the Ministry of Higher Education and Scientific Research, Government of Iraq.