High anti-HLA response in women exposed to intrauterine transfusions for severe alloimmune hemolytic disease is associated with mother-child HLA triplet mismatches, high anti-D titer, and new red blood cell antibody formation

The influence of antibody on antibody formation to particulate antigen was examined in the rabbit with special reference to the importance of immunoglobulin type, the amount and relative proportion of antigen and antibody involved, and the specificity of this influence. 19S as well as 7S antibody was shown to be an effective inhibitor of antibody formation, although there was some evidence that 7S antibody was the more efficient of the two in doing so. The inhibitory effect of antibody was found to be specific for homologous antigenic determinants. Both 19S and 7S antibody were also able to enhance antibody formation. In contrast to the suppressive phenomenon, however, enhancement appeared to be nonspecific since antibody reactive with homologous (sheep red blood cell) determinants could enhance the response not only to homologous determinants but to heterologous (dinitrobenzene) determinants conjugated to the red blood cells as well. Smaller amounts of antibody were needed to enhance than to suppress antibody formation, and suppression and enhancement depended to some extent on the amount of antigen as well as to the amount of antibody used. The enhancing and suppressing influence of antibody on antibody formation appeared to be exerted concomitantly, for the response to some antigenic determinants was sometimes suppressed at the same time that the response to others was enhanced. It is suggested that enhancement or suppression of immunologic responses by antibody represents a different balance of at least two competing factors operating together: specific neutralization of appropriate determinants thus decreasing the total effective concentration of these determinants available to stimulate the formation of antibodies, and a nonspecific increase in the availability of antigen to immunologically competent cells.

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Frequencies and Specificities of “Enzyme-Only” Detected Erythrocyte Alloantibodies in Patients Hospitalized in Austria: Is an Enzyme Test Required for Routine Red Blood Cell Antibody Screening?

Journal of Blood Transfusion ◽

10.1155/2014/532919 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 9

Author(s):

Dietmar Enko ◽

Claudia Habres ◽

Franz Wallner ◽

Barbara Mayr ◽

Gabriele Halwachs-Baumann

Keyword(s):

Blood Cell ◽

Red Blood Cell ◽

Blood Samples ◽

Antibody Screening ◽

Indirect Antiglobulin Test ◽

Cell Antibody ◽

Antiglobulin Test ◽

Low Ionic Strength ◽

Enzyme Test ◽

Screening Result

The aim of this study was to determine the frequencies and specificities of “enzyme-only” detected red blood cell (RBC) alloantibodies in the routine antibody screening and antibody identification in patients hospitalized in Austria. Routine blood samples of 2420 patients were investigated. The antibody screening was performed with a 3-cell panel in the low-ionic strength saline- (LISS-) indirect antiglobulin test (IAT) and with an enzyme-pretreated (papain) 3-cell panel fully automated on the ORTHO AutoVue Innova System. The antibody identification was carried out manually with an 11-cell panel in the LISS-IAT and with an enzyme-pretreated (papain) 11-cell panel. In total 4.05% (n=98) of all patients (n=2420) had a positive RBC antibody screening result. Of them 25.51% (25/98) showed “enzyme-only” detected specific or nonspecific RBC alloantibodies. Rhesus and Lewis system antibodies were found the only specificities of “enzyme-only” RBC alloantibodies: all in all 4.8% (4/98) were detected with anti-E, 3.06% (3/98) with anti-Lea, 3.06% (3/98) with anti-D after anti-D prophylaxis and 1.02% (1/98) with anti-e. In total, 14.29% (14/98) showed a nonspecific RBC alloantibody result with the enzyme test. The results of the present study demonstrate that a high number of unwanted positive reactions with the enzyme technique overshadows the detection of “enzyme-only” RBC alloantibodies. (Trial Registration: K-37-13).

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Prevalence of erythrocyte alloimmunization in polytransfused patients

Einstein (São Paulo) ◽

10.1590/s1679-45082011ao1777 ◽

2011 ◽

Vol 9 (2) ◽

pp. 173-178 ◽

Cited By ~ 2

Author(s):

Roberto de Oliveira Cruz ◽

Mariza Aparecida Mota ◽

Fabiana Mendes Conti ◽

Ricardo Antônio d'Almeida Pereira ◽

Jose Mauro Kutner ◽

...

Keyword(s):

Blood Cell ◽

Red Blood Cell ◽

Blood Cells ◽

High Probability ◽

Low Frequency ◽

Albert Einstein ◽

Red Cell ◽

Hemolytic Disease ◽

High Incidence ◽

Transfusion Reactions

Objective: To determine the incidence and the rate of red blood cell alloimmunization in polytransfused patients. Methods: A polytransfused patient was defined as having received at least 6 units of red cell concentrates during a 3-month period. The records of all patients (n = 12,904) who had received red blood cell units were examined retrospectively by searching the computer database at Hospital Israelita Albert Einstein in São Paulo, Brazil, over a 6-year period, between 2003 and 2009. Results: During this time, 77,049 red cell concentrate transfusions were performed in 12,904 patients. There were 3,044 polytransfused patients, 227 of whom (7.5%) presented with irregular erythrocyte antibodies. The prevalence of alloantibody specificity was: Anti-E>anti-D>anti-K>anti-C>anti-Dia>anti-c>anti-Jka>anti-S in 227 polytransfused patients. We found combinations of alloantibodies in 79 patients (34.8%), and the most common specificities were against the Rh and/or Kell systems. These antibodies show clinical significance, as they can cause delayed hemolytic transfusion reactions and perinatal hemolytic disease. About 20% of the patients showed an IgG autoantibody isolated or combined with alloantibodies. Interestingly, a high incidence of antibodies against low frequency antigens was detected in this study, mainly anti-Dia. Conclusion: Polytransfused patients have a high probability of developing alloantibodies whether alone or combined with autoantibodies and antibodies against low frequency antigens. Transfusion of red blood cells with a phenotype-compatible with RH (C, E, c), K, Fya, and Jka antigens is recommended for polytransfused patients in order to prevent alloimmunization and hemolytic transfusion reactions.

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