E. Strobel, APTITUDE OF MONOCLONAL REAGENTS FOR BLOOD -GROUP ANTIGEN DETERMINATION IN THE CASE OF T-ACTIVATION, Infusionstherapie und Transfusionsmedizin, 22(4), 1995, pp. 249-257
Background: The lack of additional antibodies - for example anti-T - w
hich can be contained in test sera of human origin has been pointed ou
t as an advantage of monoclonal reagents in blood group serology. It w
as the aim of our study to examine whether the reactions of monoclonal
reagents are nevertheless disturbed by T activation of red blood cell
s or not. Materials and Methods: Monoclonal reagents of several manufa
cturers of the specificities anti-A, -B, -AB, -A(1), -H, -C, -c, -D, -
E, -e, -K, -Jk(a), -Jk(b), -Le(a), -Le(b), -M, and -N were tested. For
this study we examined sialidase-treated and not treated red blood ce
lls with and without the tested blood group antigen by the reagent usi
ng the tube centrifugation method. Results: We found no significant di
sturbances for the monoclonal reagents of the AB0-system, A subgroups,
Rhesus system, Kidd system, Kell antigen, and Le(b) antigen. Monoclon
al anti-M and anti-N showed missing reactivity with sialidase-treated
erythrocytes, which is already known from polyclonal test sera. Most o
f the monoclonal anti-Le(a) reagents showed strong false-positive reac
tions with T-positive Le(a-) erythrocytes. After several absorptions o
f one of the monoclonal anti-Le(a) reagents with T-activated Le(a-b-)
red blood cells, the reactivity of the reagent with the Le(a) antigen
and the T antigen had disappeared. Conclusions: In contrast to the oth
er monoclonal reagents for most of the monoclonal anti-Le(a) reagents
the lack of additional anti-T antibodies does not indicate the lack of
false-positive reactions. This cross-reactivity might be caused by th
e fact that the type 1 chain antigen Le(a) and the type 3 chain antige
n T have the same terminal saccharide (galactose) in beta 1 --> 3 conn
ection to the preterminal saccharide of their peripheral core structur
e.