How are warm auto antibodies?

➢ Autoantibodies that bind optimally to red blood cells at 37 °C (98.6 °F) are categorized as warm-reacting. ➢ Warm autoantibodies react optimally at temperatures of 35°C–40°C, whereas cold agglutinins and other coldreactive autoantibodies react maximally at 4°C. ➢ Warm antibody hemolytic anemia is the most common form (80 percent) of autoimmune hemolytic anemia; it is more common among women ➢ Warm autoantibodies are typically polyclonal IgG (+/- complement) but may also be IgM or IgA. ➢ Complement activation plays a definitive but limited role in warm-antibody AIHA (w-AIHA). ➢ Most are IgG1 subclass antibodies reactive with Rh antigen IgG3 more activation C, then IgG1 than 2 then 4