الفهرس 
INTRODUCTION AND AIM OF THE WORKOnly 14 pages are availabe for public view
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Abstract
Interest in the fete-maternal immunological
axis has always interested immunologists as it
defied all rules of transplantation; the fetus
being considered a semiallogeneic graft. Thus,
understanding the phenomenon of pregnancy immune
silence will help the clinicians to improve
morbidity and mortality rates of immune-mediated
fetal and maternal disease of gestation (Feinberg
and Goink, 1991).
The observation that T cell mediated many of
their effects via secretion of cytokines had led
to the hypothesis that a proper maternal immune
response can influence growth and survival of the
fete-placental unit by local cytokine production.
Thus, the concept has emerged that there are
beneficial cytokines which can enhance fetal
growth and survival and deleterious cytokines
which can compromise pregnancy causing the death
of the fete-placental unit (Chaouet et al., 1990).
Since THl cytokines [ interleukin-2 ( IL-2) ,
interferon-gamma (IFN-gamma) and tumor necrosis
factor (TNF)] are generally harmful to the
maintenance of pregnancy, a hypothesis was put
that the conceptus protects itself by secreting
TI!2 cytokincs (IL-4, IL-5, IL-6 and IL-10) which
downregulate the harmful cytokines. As a
consequence, the maternal immune system during
pregnancy preferentially mounts TH2 biased
response (Wegmann et al., 1993).