INCREASED PRODUCTION OF BETA(2)-MICROGLOBULIN AFTER HEART-TRANSPLANTATION

Serum beta(2)-microglobulin (beta(2)m) levels were measured to evaluat e the state of immunoactivation in stable heart transplant recipients. Serum beta(2)m and renal function of 29 heart transplant recipients w ere compared with 16 control subjects, who were age and sex matched, a nd 11 patients with chronic kidney failure. Serum creatinine and 24-ho ur urine collection for albuminuria were used as markers of renal impa irment. Heart transplant recipients with normal renal function (n = 7) had significantly elevated beta(2)m levels compared with control subj ects: 2.6 +/- 0.9 vs 1.66 +/- 0.32 mu g/ml, p less than or equal to 0. 05. Heart transplant recipients with impaired renal function (n = 22) had significantly elevated beta(2)m compared with the chronic kidney f ailure group: 4.42 +/- 1.3 vs 3.49 +/- 0.66 mu g/ml (p less than or eq ual to 0.05); although there was no significant difference in serum cr eatinine levels. Albuminuria excretion was significantly elevated in t he chronic kidney failure group compared with the heart transplant rec ipients with impaired renal function (p less than or equal to 0.05). E levated serum beta(2)m in heart transplant recipients suggests increas ed beta(2)m production, reflecting increased immunoactivation. This ob servation could be useful in monitoring longterm immunosuppressive the rapy.