Increased beta 2-microglobulin-free HLA class I heavy chain serum levels in the course of immune responses to viral antigens and to mismatched HLA antigens
F. Puppo et al., Increased beta 2-microglobulin-free HLA class I heavy chain serum levels in the course of immune responses to viral antigens and to mismatched HLA antigens, TISSUE ANTI, 55(4), 2000, pp. 333-341
Besides being present in serum in association with beta 2-mu, HLA class I h
eavy chains are also present in serum as beta 2-mu-free moieties. The incre
ase in serum levels of beta 2-mu-associated HLA class I heavy chains in con
ditions associated with an activation of the immune system have prompted us
to measure the serum levels of beta 2-mu free HLA class I heavy chains in
the course of immune responses to viral antigens and to mismatched histocom
patibility antigens. The serum level of beta 2-mu-free HLA class I heavy ch
ains, like that of beta 2-mu-associated HLA class I heavy chains was signif
icantly increased in patients affected by advanced HIV-1 infection or by ch
ronic hepatitis C (CHC). In the latter group of patients an association was
found between a reduction in the beta 2-mu free HLA class I heavy chain se
rum level and response to therapy with interferon alpha and ribavirin. More
over, the beta 2-mu-free HLA class I heavy chain serum level was increased
more than that of beta 2-mu-associated HLA class I heavy chains during epis
odes of liver ischemia following liver transplantation and in the course of
acute graft rejection and of acute graft-versus-host-disease (GVHD) after
allogeneic bone marrow transplantation (BMT). These results suggest that th
e serum levels of beta 2-mu-free and beta 2-mu-associated HLA class I heavy
chains are independently regulated. Furthermore, beta 2-mu-free HLA class
I heavy chain serum level may be a useful marker to monitor response to the
rapy in CHC patients and the clinical course of liver and bone marrow graft
s.