<p>Produced by plasma cells in the spleen, bone marrow and lymph nodes. Since it is around five times larger than "normal" antibody it does not diffuse quickly or enter tissues readily and as such its concentration in extracellular fluid and lymph is very low. It does not cross the placenta even in animals with haemochorial placentas e.g. apes. </p> | <p>Produced by plasma cells in the spleen, bone marrow and lymph nodes. Since it is around five times larger than "normal" antibody it does not diffuse quickly or enter tissues readily and as such its concentration in extracellular fluid and lymph is very low. It does not cross the placenta even in animals with haemochorial placentas e.g. apes. </p> |