Spleen and liver weight changes in NZB mice with haemolytic anaemia.

Spleen and liver weights from 998 NZB mice were subjected to computerised multivariate analysis. 3-dimensional graphs relating predicted spleen and liver weights to age and bodyweight were prepared and the relationship of the fitted surface to the histology and pathological autoantibody is discussed. On the basis of spleen weight increase, red-cell destruction throughout the greater part of life seems to be mainly intrasplenic, while intrahepatic destruction does not become important until later, when it is probably a dominant feature in the terminal period of the disease. Only limited organ weight increases occur in breeding females, and it is suggested that pregnancy lessens the effect of the haemolytic disease, the 'protective' effect extending long after the cessation of breeding.