Clin. exp. Immunol. (1992) 90, 36-42
IL-2 regulation of soluble IL-2 receptor levels following thermal injury J. A. TEODORCZYK-INJEYAN, B. G. SPARKES*, S. LALANI, W. J. PETERSt & G. B. MILLSt Department of Surgery and Sunnybrook Health Science Centre, University of Toronto, *Defence and Civil Institute of Environmental Medicine, tThe Ross Tilley Burn Centre, Wellesley Hospital, and IDepartment of Oncology Research, Toronto General Hospital, Toronto, Ontario, Canada
(Acceptedfor publication 12 June 1992)
SUMMARY In the immunosuppressed burn patient serum levels of both IL-2 and a soluble form of IL-2 receptor alpha (sIL-2R1x) are significantly elevated. Strikingly, the production of these markers by the in vitro activated patients' cells is decreased. This study examines the role of IL-2 in the decreased production of the sIL-2Ra in vitro in patients with major burns (n = 18, 30 to > 70% total body suface area). Peripheral blood mononuclear cell (PBMC) cultures from patients with highly elevated serum sIL2Ra, and from healthy controls (n = 12) were activated with concanavalin A (Con A) at initiation. In patients' cultures mitogen-induced increments of sIL-2Roa levels were significantly lower. There was a significant negative correlation (r= -0-64, P 100-1900)
566 +471
1355 + 358 (810-2100)
2048+850 (880-2700)
(0-1210) ND
2115+927 (1030-3100)
PBMC cultures from immunosuppressed burn patients (n = 5) and normal donors (n = 3) were stimulated with concanavalin A (Con A, 10 or phytohaemagglutinin (PHA, 10 jug/ml). Levels of sIL-2Ra (U/ jug/ml) ml) in supernatants from parallel cultures harvested after 3 or 7 days of
cultivation were determined as described in Patients and Methods. NDNodermn. ND, Not determined.
pleted cultures were prepared by first incubating PBMC (5 x I06/ml) in 60 x 15 mm plastic culture dishes (Corning, Corning, NY) at 370C for 90-120 min. Following the incubation, non-adherent cells were removed by washing with warm RPMI 1640, centrifuged and resuspended (1 x 106/ml) in fresh culture medium for further studies. A T lymphocyte-enriched population was obtained through a double resetting technique with 2-aminoethylisothiouronium bromide-treated sheep erythrocytes [15].
Culture system Levels of soluble IL-2Roe in supernatants of patients' cells cultured in the presence of mitogen Con A (10 pg/ml) are markedly reduced compared with controls [3]. This may result from inadequate transmembrane signalling by Con A and/or altered kinetics of IL-2Rox synthesis and release from the cells' surface by burn patients' PBMC. Therefore, in preliminary studies, the culture period was extended to 7 days and Con Ainduced IL-2Ra release was compared with that of another lectin, PHA (10 jug/ml). In Con A-activated cultures, the cumulative soluble IL-2Ra levels increased in time, both in control and patients' samples (Table 1). However, due to a wide variability in soluble IL-2Ra concentrations in patients' preparations, time-related increases in IL-2Roc release (Table 1) were not significant. Notably, the mean patients' secretion of IL-2Rac after 7 days remained significantly (P
IL-2 regulation of soluble IL-2 receptor levels following thermal injury J. A. TEODORCZYK-INJEYAN, B. G. SPARKES*, S. LALANI, W. J. PETERSt & G. B. MILLSt Department of Surgery and Sunnybrook Health Science Centre, University of Toronto, *Defence and Civil Institute of Environmental Medicine, tThe Ross Tilley Burn Centre, Wellesley Hospital, and IDepartment of Oncology Research, Toronto General Hospital, Toronto, Ontario, Canada
(Acceptedfor publication 12 June 1992)
SUMMARY In the immunosuppressed burn patient serum levels of both IL-2 and a soluble form of IL-2 receptor alpha (sIL-2R1x) are significantly elevated. Strikingly, the production of these markers by the in vitro activated patients' cells is decreased. This study examines the role of IL-2 in the decreased production of the sIL-2Ra in vitro in patients with major burns (n = 18, 30 to > 70% total body suface area). Peripheral blood mononuclear cell (PBMC) cultures from patients with highly elevated serum sIL2Ra, and from healthy controls (n = 12) were activated with concanavalin A (Con A) at initiation. In patients' cultures mitogen-induced increments of sIL-2Roa levels were significantly lower. There was a significant negative correlation (r= -0-64, P 100-1900)
566 +471
1355 + 358 (810-2100)
2048+850 (880-2700)
(0-1210) ND
2115+927 (1030-3100)
PBMC cultures from immunosuppressed burn patients (n = 5) and normal donors (n = 3) were stimulated with concanavalin A (Con A, 10 or phytohaemagglutinin (PHA, 10 jug/ml). Levels of sIL-2Ra (U/ jug/ml) ml) in supernatants from parallel cultures harvested after 3 or 7 days of
cultivation were determined as described in Patients and Methods. NDNodermn. ND, Not determined.
pleted cultures were prepared by first incubating PBMC (5 x I06/ml) in 60 x 15 mm plastic culture dishes (Corning, Corning, NY) at 370C for 90-120 min. Following the incubation, non-adherent cells were removed by washing with warm RPMI 1640, centrifuged and resuspended (1 x 106/ml) in fresh culture medium for further studies. A T lymphocyte-enriched population was obtained through a double resetting technique with 2-aminoethylisothiouronium bromide-treated sheep erythrocytes [15].
Culture system Levels of soluble IL-2Roe in supernatants of patients' cells cultured in the presence of mitogen Con A (10 pg/ml) are markedly reduced compared with controls [3]. This may result from inadequate transmembrane signalling by Con A and/or altered kinetics of IL-2Rox synthesis and release from the cells' surface by burn patients' PBMC. Therefore, in preliminary studies, the culture period was extended to 7 days and Con Ainduced IL-2Ra release was compared with that of another lectin, PHA (10 jug/ml). In Con A-activated cultures, the cumulative soluble IL-2Ra levels increased in time, both in control and patients' samples (Table 1). However, due to a wide variability in soluble IL-2Ra concentrations in patients' preparations, time-related increases in IL-2Roc release (Table 1) were not significant. Notably, the mean patients' secretion of IL-2Rac after 7 days remained significantly (P
