In vitro and in vivo immunologic parameters were determined in 26 patients treated continuously with
cyclosporine to prevent
graft-versus-host-disease (GVHD) after allogeneic
bone marrow transplantation (BMT) for acute and chronic
leukemia and for
aplastic anemia. A group of 18 patients was tested 6 months after BMT and another group of 10 patients was tested after one year. At 6 months after BMT, 94% of the patients had normal serum
IgG and
IgM levels, whereas at one year 29% of them had low
IgA levels. The proportion of patients with normal lymphocyte responses in vitro at 6 months after BMT was 69% and 76% for the responses to
concanavalin A and to soluble
antigens; 75% and 53% for the responses to allogeneic cells and
pokeweed mitogen, respectively; and 89% for the response to
phytohemagglutinin. All but one were able to generate suppressor cells upon con A stimulation. At one year after the graft, only one patient had demonstrable
multiple abnormalities in in vitro tests. Skin test reactivity at one year was comparable to pre-graft reactivity. After BMT a
lymphopenia persisted for 6 months. The rate of infectious complications was high during the first 3 months after BMT, and it diminished progressively as immune functions returned to normal.
Infection was the cause of death in two cases (one disseminated
cytomegalovirus infection and one
septicemia). GHVD occurred in 12 patients; in nine of them the disease was transient and mild, only 1 patient developed severe chronic GVHD. Acute GVHD did not influence the
tempo of immunologic reconstitution. In comparison to other studies, it seems that
cyclosporine does not delay immune restoration, or increase morbidity from
infection, while preventing GVHD and its complications efficiently.