Anti‐Wr^b, and Other Autoantibodies Responsible for Positive Direct Antiglobulin Tests in 150 Individuals

Abstract

Eluates from the red blood cells (and sera whenever free autoantibody was present) of 150 individuals with positive direct antiglobulin tests, have been studied for antibody specificity. Of 87 patients with AIHA, 64 had autoantibodies reacting with all red cell samples including Rhnu11. Of these 64 anti-d1 autoantibodies, two were, and 32 contained, auto-anti-Wrb. Of 33 patients being treated with alphamethyldopa, who had developed positive direct antiglobulin tests, 23 had anti-d1 autoantibodies four of which contained auto-anti-Wrb. Of 30 haematologically normal donors with positive direct antiglobulin tests, 23 had anti-d1 autoantibodies, two of which were, and six of which contained, auto-anti-Wrb. The full specificities of autoantibodies, other than anti-Wrb and anti-d1, in the 150 patients are described, as are the natures of the protein red cell coatings that caused the positive direct antiglobulin tests. The presence of free serum autoantibody as a correlate of the three clinical conditions is reported. Several observations on auto-anti-Wrb are documented. The antibody can cause gross red cell destruction in vivo, but can be benign on other occasions; it occurs with approximately the same frequency in AIHA patients and "normal" donors with positive direct antiglobulin tests, but in fewer patients with alphamethydopa induced positive direct antiglobulin tests; it does not activate complement in vivo; and finally it may eventually provide a clue to the aetiology of AIHA.

Warm-reactive Autoantibodies in Pediatric Patients

“…This finding is similar to other series in which the DAT was reactive for IgG alone in 21% to 56% of patients and the DAT was reactive for both IgG and C3 in 31% to 64% of patients. 3,5,[10][11][12][13][14] When the serologic features of patients' DAT tests are evaluated carefully, important conclusions can be drawn with respect to hemolysis. In this study, there was a clear correlation with the DAT reaction strength for IgG and the likelihood of hemolysis.…”

A Simple Method for the Rapid and Selective Absorption of Warm-Reactive Erythrocyte Autoantibodies from Serum

“…Freez-cessibility of antigenic binding sites after ing and thawing in combination with elution protease treatment of erythrocytes (table II, No. [13][14][15]. It is also shown that the heat elution technique in combination with pro tease treatment of erythrocytes [17,21] by far is not as efficient for the preparation of erythrocytes used for the autoabsorption of antibodies as the method described in this paper (table II, No.…”

“…Further, some 78% of subjects with 'warm' antibody-induced hemolytic anemia and some 27% in whom the autoantibodies are benign have free autoantibody present in their sera [10,13]. In those individuals in whom red cell transfusions are considered, it is necessary that the autoantibody be re moved from the serum in order that allo antibodies simultaneously present be identi fied [7,[10][11][12]15,16,21].…”

Autoimmune Hemolytic Anemia Associated with Autoanti-Ge

“…Thus to the long list of such autoantibodies in the Rhesus [3 5, 41], Kell [22], LW [8,16], MNS [7,9], U [21,24], Wright [18], En [18], I [17], Kidd [26], and Xg [42,43] groups, we add autoantiGerbich. It should be realized, however, that these are simply convenient labels for ob served serological reactions, and that we are unable to define now the membrane struc ture toward which the antibodies are di rected.…”