MHC,HLA,TCR

Lim Lay Har sci80526 at nus.edu.sg
Tue Feb 22 02:47:58 EST 2000


1.)The binding of the TCR & the epitope is non-specific,but does it mean
that the TCR only recognise the epitope & not the associated MHC?For
exogenous antigens which binds to MHC 2,B-cells & antibodies bind more
specifically to antigens.Thus the TCR need not specifically bind to the
epitope.So does it mean that the TCR only recognise the epitope & not
both the MHC 2 & the epitope?If this is so,then why is there such a
thing as HLA incompatibility where the HLA alleles of the donor(for
example bone marrow) does not match the recipients & antibodies will be
produced against the incompatible HLA alleles?Are non-self HLA alleles
considered as antigens or MHC molecules?HLA alleles are made up of
DNA,which is supposed to have low immunogenicity,so why is there a such
immune response against incompatible HLA alleles from a donor?Could it
be the histones(protein) associated with the HLA alleles that increases
the immunogenicity? 

2.)Tumour cells bind to MHC 1 & the tumour antigen & MHC 1 binds to the
receptor of cytotoxic T cells.B cells & antibodies are not involved,so
how can the cytotoxic T cell receptor only recognise the epitope & not
the associated MHC 1?Doesn't mutations occur in the MHC 1 of tumour
cells? 







More information about the Immuno mailing list