Previous data obtained from a limited number of patients with lymphoproliferative
diseases in this and other laboratories4’’8 suggested that S.Ig
provide useful markers of proliferating B lymphocytes, but the studies have
led to somewhat contradictory results. The purpose of the present study was
to characterize, by a direct immunofluorescence procedure on living cells,
the S.Ig on the lymphocytes of more than 100 patients with lymphoproliferative
disorders in order to evaluate their origin, significance and usefulness
in the study of hematological diseases.