Immunological disorders--the evolution of an hypothesis.

In honouring the memory of Dr Alwyn Zoutendyk, a respected member of the staff of the South African Institute for Medical Research, attention is called to the studies of the immunological disorders. While investigating serum hepatitis affecting soldiers of the US army following the administration of yellow fever vaccine, an antigen similar to that later called the Australia antigen, now hepatitis B surface antigen, was found in the acute phase serum and the corresponding antibody was found in convalescence. This finding and subsequent studies suggested there was a group of disease, which we called the hyperreactive auto-allergic disorders, of which examples were to be found in every system. The obverse of these we called the hyporeactive immunologically deficient disorders resulting from defects of the cell or serum components of the immunological reactions, of which many examples have also been found.