COMBINED SIMULTANEOUS KIDNEY BONE MARROW TRANSPLANTATION/

On the basis of observations in patients with longterm (28-30 years) r enal allograft survival, all of whom had evidence of systemic microchi merism, we began a program of combined simultaneous kidney/bone marrow transplantation. Between 12/14/92, and 10/31/94, 36 kidney transplant recipients received 36 x 10(8) unmodified bone marrow cells/kg; 6 pat ients also received pancreatic islets, and 7 patients also received a pancreas. The mean recipient age was 39.0+/-10.8 years, and the mean d onor age was 31.8+/-16.1 years; the mean cold ischemia time was 23.0+/ -9.1 hr. Twenty control patients received kidneys alone, mainly becaus e of refusal by the donor family to consent to vertebral body recovery ; 3 of these patients also received a pancreas. The mean recipient age was 47.9+/-11.7 years, and the mean donor age was 41.5+/-17.9 years; the mean cold ischemia time was 28.6+/-6.2 hr. All patients received t acrolimus-based therapy, without radiation, cytoreduction, or inductio n antilymphocyte preparations. Blood was drawn prior to and at regular intervals after transplantation for detection of chimerism and for im munologic studies, With a mean follow-up of 11.1+/-5,8 months, all 36 study patients are alive, and 33 (92%) have functioning allografts wit h a mean serum creatinine of 1.9+/-1.2 mg/dl and a BUN of 26+/-9 mg/dl , Graft vs, host disease was not seen in any patient. The incidence of rejection was 72%; 11% of the patients required OKT3 or ATG for stero id-resistant rejection, The incidence of CMV was 14%, and that of dela yed graft function was 17%. A total of 18 (90%) control patients are a live, and 17 (85%) have functioning allografts, with a mean serum crea tinine of 2.1+/-1.3 mg/dl, and a BUN of 30+/-13 mg/dl. The incidence o f rejection was 60%, and 10% required OKT3 or ATG, CMV was seen in 15% , and delayed graft function in 20% (P=NS), In the study patients, chi merism was detected in the peripheral blood of 30 of 31 (97%) evaluabl e patients by either PCR or flow cytometry. In the control patients, c himerism was seen in 9 of 14 (64%) evaluable patients (P<.02). Decreas ing donor-specific responsiveness was seen in 6/29 (21%) evaluable stu dy, and 4/14 (29%) evaluable control patients (P=NS), We conclude that combined kidney/bone marrow transplantation is associated with accept able patient and graft survival, augmentation of chimerism, and no cha nge in the early events after transplantation.