What do cold-reacting antibodies typically react with at low temperatures?

Cold-reacting antibodies are primarily associated with the reaction to red blood cells at lower temperatures, especially those found in the cold agglutinin syndrome. These antibodies, usually of the IgM class, tend to agglutinate red blood cells when exposed to cold temperatures (typically below 37°C).

This phenomenon is significant in clinical scenarios where patients may present with hemolytic anemia due to the agglutination of their red blood cells when their body temperatures drop, such as during exposure to cold environments. Cold agglutinins target specific antigens on the surface of red blood cells, leading to their clumping and potential destruction by the immune system.

In contrast, complement proteins are part of the immune system that can interact with antibodies but are not specifically targeted by cold-reacting antibodies. White blood cells and platelets are not typically involved in reactions specific to cold-reacting antibodies, as these conditions primarily affect red blood cells. Understanding the interaction of cold-reacting antibodies is crucial in diagnosing and managing conditions associated with cold agglutination.