Prevention of platelet alloimmunization in dogs with systemic cyclosporine
and by UV-irradiation or cyclosporine-loading of donor platelets
SJ Slichter, HJ Deeg and MS Kennedy
To study the immunosuppressive effects of three different treatments, 30
dogs received at weekly intervals eight platelet transfusions from a single
random donor dog. The three experimental protocols were daily oral
cyclosporine (Cs) treatment of recipients; in vitro ultraviolet
(UV)-irradiation of donor platelets; and Cs-loading of donor platelets. All
nine recipients of Cs, 11/12 (92%) recipients of UV-irradiated platelets,
and 5/9 (56%) recipients of Cs-loaded donor platelets remained nonimmunized
to repeated transfusions of donor platelets. In contrast, only 3 of 21
untreated controls (14%) were not alloimmunized by donor platelets.
Moreover, 44% to 67% of the nonimmunized recipients remained tolerant to
continued platelet transfusions from their original donor even after
experimental therapy was discontinued. Forty- three percent to 100% of
transfusions from secondary donors were also accepted without causing
alloimmunization, suggesting that tolerance induced by prior treatment was
not specific for the primary donor. However, survival of both the original
and secondary donor platelets was reduced to about half the starting level,
suggesting that some immune response to platelets had occurred. Also,
recipients immunized by their original donor's platelets frequently
developed refractoriness to platelets from other donors.
Volume 69,
Issue 2,
pp. 414-418,
02/01/1987
Copyright © 1987 by The American Society of Hematology
