Prevention of MHC-alloimmunization by UV-B irradiation in a murine model: effects of UV dose and number of transfused cells

Br J Haematol. 1994 Jul;87(3):598-604. doi: 10.1111/j.1365-2141.1994.tb08319.x.

Abstract

The optimal dose of UV-B radiation for prevention of in vivo alloimmunization (AI) against major histocompatibility complex (MHC) antigens was investigated in a murine transfusion model. Two groups with five C57BL/6 mice (H-2b) each were transfused at weekly intervals with 1 x 10(5) or 1 x 10(6) DBA/2 (H-2d) leucocytes. Both suspensions induced anti-H-2d antibodies in all mice after the second transfusion. The minimal UV-B dose required for abolition of alloreactivity in the mixed leucocyte reaction (MLR) was 0.6 J/cm2. This dose completely prevented the onset of MHC-AI in all five mice transfused with six suspensions containing 1 x 10(5) leucocytes. In contrast, suspensions with 1 x 10(6) leucocytes and exposed to 0.6 J/cm2 induced immunization in 4/5 mice. Further increase of the dose to 1.8 or 5.4 J/cm2 did not prevent the onset of MHC-AI. The use of UV radiation for prevention of secondary MHC-AI was investigated in five mice with a primed immune system. Transfusion of suspensions with 1 x 10(5) leucocytes and irradiated at a dose of 1.8 J/cm2 did not prevent booster reactions. We conclude that the number of leucocytes per transfusion determines the efficacy of UV irradiation for the prevention of MHC-AI. For UV irradiation of human platelet concentrates (PCs) we propose to reduce the number of leucocytes by centrifugation prior to UV exposure. UV-B irradiation of PCs with high numbers of leucocytes may not be effective for prevention of alloimmunization.

MeSH terms

  • Animals
  • Blood Platelets / immunology
  • Blood Platelets / radiation effects
  • Dose-Response Relationship, Radiation
  • Isoantibodies / immunology*
  • Leukocyte Transfusion / adverse effects*
  • Leukocytes / immunology
  • Leukocytes / radiation effects
  • Major Histocompatibility Complex / immunology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred DBA
  • Platelet Transfusion
  • Ultraviolet Rays*

Substances

  • Isoantibodies