Correlation of soluble-interleukin-2 recptor levels and engraftment with acute graft versus host disease in patients receiving allogeneic bone marrow transplants
Acute graft versus host disease (aGvHD) is a potentially fatal complication occurring after allogène; bone marrow transplantation (BUT), involving gut. liver and skin. The diagnosis of GvHD is mainly based on clinical evaluation, obtaining biopsies is often not possible due to thrombocytopenia. Confirmation of diagnosis is therefore difficult as clinical symptoms of GvHD often resemble those of organ toxicity, drug rash or infection. GvHD is mediated by activated T-cells of donor origin, expressing interleukin-2 receptor (IL-2R) and shedding its a-subunit, detectable in the serum as soluble IL-2R (slL-2R). We measured slL-2R levels following BUT in order to evaluate its value as indicator for the onset of aGvHD. In 12 patients (pts), undergoing allogène BUT weekly evaluations of sIL2R in previously frozen samples were performed with an ELISA. 3 pts developed no aGvHD (group a), 4 pts developed grade 1 to 2 aGyHD (group b) and 5 pts developed GvHD grade 3 and 4 (group c). Statistics were performed using Mann-Whitnay and Spearman rank. - We found a significant correlation between SIL-2R level and severity of aGvHD (r=0.8, p=0.008) The slL-2R levels peaked around day 14 after BMT in pts with aGvHD (group b+c), no peak was seen in pts without aGvHD (group a). Peak levels were higher in group c than in group b (difference between group a vs. b or c was significant, p<0.04). A significant correlation between the day of engraftment (neutrophil count >0 5x109/l) and the severity of GvHD could also be established (r=0.5, p=0.03). The SIL-2R levels correlated nicely with the duration of hospitalization (r=0.8, p=0.008). Tabla 1: Median SIL-2R levels (U/ml serum) and median day to engraftment, (day until the absolute neutrophil count was sustained >0.5x109/l). Grdt GvHD~ ~TJL-2R lvl (U/ml) day to tnnriftnwnt none 1193 11 1 and 2 2164 17 3 and 4 4606 20 We conclude that slL-2R-levels in the serum of pts after altogeneic BMT might be an indicator for aGvHD, reflecting the severity of the disease. In pts, engrafting late the risk of the onset of GvHD is increased, therefore especially those pts should be monitored closely.