EFFECTS OF MONOCLONAL-ANTIBODY AGAINST CD45RB ON PERIPHERAL-BLOOD MONONUCLEAR CELL-PROLIFERATION AND ON HLA-DR AND ADHESION MOLECULE EXPRESSION ON THYROCYTES OF PATIENTS WITH AUTOIMMUNE THYROID-DISEASE
M. Nishikawa et al., EFFECTS OF MONOCLONAL-ANTIBODY AGAINST CD45RB ON PERIPHERAL-BLOOD MONONUCLEAR CELL-PROLIFERATION AND ON HLA-DR AND ADHESION MOLECULE EXPRESSION ON THYROCYTES OF PATIENTS WITH AUTOIMMUNE THYROID-DISEASE, Thyroid, 5(4), 1995, pp. 265-272
To evaluate the role of CD45 (especially that of the ectodomain region
B) on immunocyte-thyrocyte signaling in patients with autoimmune thyr
oid disease (AITD), we have examined the in vitro and in vivo effects
of a monoclonal antibody (mAb) against CD45RB, termed MT3, MT3 was add
ed to cultured peripheral blood mononuclear cells (PBMC) from patients
with AITD and was additionally injected into severe combined inmunode
ficient (SCID) mice to which Graves' thyroid cells and intrathyroidal
lymphocytes were engrafted, MT3 stimulated proliferation of PBMC when
cultured for 2 to 3 days in patients with Hashimoto's thyroiditis (HT)
and Graves' disease (GD) and in normal controls (NC), However, when c
ultured for 7 days, the stimulation index CSI: counts per minute (cpm)
with mAb/cpm without mAb] was lowered by MT3 in NC and GD patients, H
owever, the mean SI was not lowered in patients with HT, In SCID mice,
the concentrations of human immunoglobulin G, antithyroglobulin and a
ntithyroperoxidase antibodies in sera were not significantly changed b
y injecting MT3, The expression of human leukocyte antigen (HLA)-DR an
d intercellular adhesion molecule (ICAM)-1 on engrafted human thyrocyt
es decreased after the tissues were engrafted into the control mice to
which vehicle alone was injected, However, in the mice injected with
MT3, HLA-DR and ICAM-1 expression remained high or up-regulated by the
injection, These data suggest that modulation of the region B of CD45
by MT3 enhances lymphocyte proliferation; lymphocytes in HT patients
may have an abnormality in CD45RB distribution and/or signal transduct
ion via CD45, and CD45RB-related immunocyte-thyrocyte signaling is inv
olved in HLA-DR and ICAM-1 expression on Graves' thyroid cells.