Production of human alloreactive antibodies by uremic sensitized lymphocytes engrafted in severe combined immunodeficient mice.
BACKGROUND
Numerous studies have documented antibody responses to nominal antigens in human peripheral blood lymphocyte (hu-PBL)-severe combined immunodeficient (SCID) mice engrafted with PBL. We suggest, therefore, that engraftment of SCID mice by allosensitized cells produces alloreactive antibodies (allo-Ab). As such, SCID mice can be used as a model to examine the cellular basis of the sustenance of humoral alloresponses.


METHODS
C.B-17 SCID mice were engrafted intraperitoneally with PBL from sensitized uremic patients for 5 weeks and classified into the following: group 1, 8 mice engrafted with unactivated cells (n = 5; n = sensitized patients); group 2, 6 mice engrafted with unactivated PBL (n = 3) followed 2 days later by in vivo activation with interleukin-2 (IL-2) and lipopolysaccharide (LPS); group 3, 11 mice engrafted with cells preactivated in vitro with IL-2 and LPS (n = 6); group 4, 9 mice engrafted with cells preactivated with irradiated allogeneic transformed B cells, IL-2, and LPS (n = 5); group 5, 10 mice engrafted with cells preactivated with IL-2, LPS, and HLA class II allopeptides and adjuvant (n = 6); group 6, 8 control mice engrafted with control cells preactivated with IL-2 and LPS. Two weeks later, each group was rechallenged by the same stimuli. Allo-Ab production was measured by the panel-reactive antibody PRA-STAT ELISA method. Results. Allo-Ab was produced in 54.5% of group 3, 43% of group 4; 80% of group 5, and 0% of groups 1, 2, and 6. The ratio of alloreactive positive wells in the allo-Ab-producing PBL-hu-SCID mice to that present in the respective patient's sera was 82%, 52%, and 87% in groups 3, 4, and 5, respectively. Conclusions. The study demonstrates the feasibility of using the hu-PBL-SCID model to study alloreactive memory B-cell function in humans. Discrete HLA-class allopeptides (group 5) appeared more potent allo-Ab producers than allogeneic cells (group 4).
Shoker
A
A
Department of Medicine, Royal University Hospital, Saskatoon, Saskatchewan, Canada. shoker@sask.usask.ca
Sardar
Z
Z
Yang
H
H
Hussain
M
M
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000328:Adult; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology / Q000528:radiation effects; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000494:pharmacology; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D007518:Isoantibodies / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000502:physiology; D017710:Lymphocyte Transfusion; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology*; D008297:Male; D051379:Mice; D016513:Mice, SCID / Q000276:immunology*; D014511:Uremia / Q000276:immunology*
D000276:Adjuvants, Immunologic; D000949:Histocompatibility Antigens Class II; D007376:Interleukin-2; D007518:Isoantibodies; D008070:Lipopolysaccharides