THE PROLIFERATIVE RESPONSE AND THE PLCg1 EXPRESSION TO THE CO-STIMULATION IN THE
CORD BLOOD LYMPHOCYTES
He ZJ, Chen TX, Ying DM, Wu SM
Xinhua Hospital, Shanghai Second Medical
University, Shanghai, China
Objective: To investigate the
mechanism of dysfunction in neonatal T and B lymphocytes.
Methods:
The proliferative response to
the co-stimulation Anti-CD3 plus Anti-CD28 monoclonal antibody or to
trans-membrane stimulation PMA plus IM were assayed by [3H]-TdR cooperation
method. The intra-cellular Ca2+ concentration was measured by
Fura-2/AM labeled method, after the co-stimulation or the trans-membrane
stimulation was given. The PLCg1 expression was detected by Western Blot.
Results: The proliferation of cord blood lymphocytes could
be improved with the co-stimulation or the trans-membrane stimulation, the
later one being close to the adult's level, but the improved proliferation
could not reach the level of adult. The increase of Ca2+
concentration and the improvement of the proliferation might be induced by the
co-stimulation or trans-membrane stimulation. When giving the individual stimulator
alone, the Ca2+ concentration of lymphocytes could increase,
whereas the proliferation of lymphocytes could not be enhanced. The PLCg1 expression was also lower in both the stimulated and non-stimulated
lymphocytes from cord blood.
Conclusion: The mechanism of the dysfunction in the
lymphocytes from cord blood was very complicated. The dysfunction may
mainly exist in the early stage of the activation event, but the downstream
may be also involved. It was not affected by one single pathway, one single
factor, or affected by simply accumulation of several factors, but the comprehensive
interaction of many factors.