In article <348ACA81.65DC at tribe.fit.unimas.my>, K.Nirmalan
<URL:mailto:a9631274 at tribe.fit.unimas.my> wrote:
> Hello everyone.....
> I need you people's help...
>> Can anybody explain to me how does Rh- antibody kills the Rh+ red blood
> cell... what are the mechanisms, cells and organs involved?
>> Lastly.... how does RhoGAM works? (mechanisms)
>> Thank you... your helps are very much appreciated....this is very
> urgent.......pleaseeeeeee
>It is commonly accepted that the mechanism by which anti-Rh antibodies kill
Rh +ve cells is through the binding of the IgG antibodies to Fc receptors
on phagocytic cells such as macrophages. Organs thought to be involved
include the spleen and liver. In Haemolytic disease of the newborn (HDN)
the mothers anti-Rh antibodies cross the placenta and trigger macrophages
to destroy the Rh postive red cells of the feotus.
RhoGAM is usually administered to a mother at about the time of birth to
prevent her from making her own anti-Rh antibodies which would then be a
problem for future pregnancies. It is not clear exactly how this works but
it is commonly suggested that the RhoGAM antibody removes antigen postive
red cells from the mothers blood and prevents "priming" of her immune
system. However another possible mechanism is that the IgG antibodies in
the RhoGAM give a negative signal to antigen specific B-cells through the
FcgRIIb receptor and this shuts down the B-cells. Further experiments are
needed to test this.
Mike Clark, <URL:http://www.path.cam.ac.uk/~mrc7/>
--
o/ \\ // || ,_ o M.R. Clark, PhD. Division of Immunology
<\__,\\ // __o || / /\, Cambridge University, Dept. Pathology
"> || _`\<,_ // \\ \> | Tennis Court Rd., Cambridge CB2 1QP
` || (_)/ (_) // \\ \_ Tel.+44 1223 333705 Fax.+44 1223 333875
