Screening of HLA-A, -B, -C and HLA-DR seric antibodies in blood donor married women. II. Study of two particular aspects of the HLA-DR immunization.

This note contains considerations about two aspects of the immunization against HLA-DR specificities. Such considerations were made during the study of the results obtained by a previous screening of the sera of 1,312 blood donor married women for the presence of HLA-A, -B, -C and -DR antibodies and by a previous collection of data about deliveries, abortions and received blood transfusions for each donor. The following techniques were used: density gradient lymphocytes separation from peripheral venous blood, C.d.L. according to N.I.H. standard technique, S.R.B.C. rosetting to obtain "B" lymphocytes, C.d.L. according to N.I.H. long incubation technique. Two observations are reported: 1) seven donors with no delivery, no abortion and no received blood transfusion (and, obviously, with no surgical transplantation) had seric antibodies against HLA-DR specificities; 2) among the donors positive for the presence of seric HLA-A, -B, -C or/and HLA-DR antibodies, the great majority (15/17) of those having three characteristics (named altogether "condition" in this note) had HLA-DR antibodies without HLA-A, -B, -C antibodies (i.e. "pure" HLA-DR antibodies). It may be the HLA-DR immunization happens in different circumstances, or happens even in different circumstances in respect to HLA-A, -B, -C immunization. Are HLA-DR antibodies synthesized, or may they be synthesized too, against spermatozoa or neo-formed zygote DR specificities?