Low-frequency Red Cell Antigen Research Articles

A rare case of clinically significant naturally occurring anti-Cw reported in a healthy male donor.

Anti-Cw antibody is an immunoglobulin against the red cell antigen Cw which is a low frequency red cell antigen that belongs to the Rh antigen system. It is a clinically significant antibody and may cause haemolysis on exposure to antigen positive red cells. Due to its low frequency, it is not included in routine antibody screening panels. A 32years healthy male donor with no history of transfusion donated whole blood at the department of Transfusion Medicine & Blood Centre of our institute. As a part of routine pre-transfusion testing, the donor's samples were subjected to automated blood grouping and screening for unexpected red cell antibodies using 3 cells panel on solid-phase red-cell adherence (SPRCA) (Galileo Neo, Immucor, Norcross, USA). The antibody screening came out to be positive with a reaction in cell I of the antibody screening panel. Further the antibody was identified as anti Cw in using 16 cells panel, select cells and phenotyping. In the present case, the anti-Cw antibody was found to be reactive at 37°C and AHG phase which could lead to haemolytic transfusion reaction. The fact that the male donor had no history of transfusion or transplant led us to the conclusion that it was a naturally occurring, but a clinically significant antibody. This case highlights the importance of performing an antibody screening for healthy donors as well and urges transfusion services to procure screening cells which incorporate Cw positive cells.

Anti‐Cw alloimmunization presenting as hydrops fetalis

C(w) is a low frequency red cell antigen that belongs to the Rh blood groups system. While not uncommon, anti-C(w) is rarely associated with clinically significant haemolytic disease of the newborn (HDN). When it does occur, it is often subclinical or of mild to moderate clinical severity. In the majority of pregnancies it is considered to be a naturally occurring antibody and has not been reported to cause hydrops fetalis or stillbirth. We report a case of anti-C(w) alloimmunization, which was associated with significant anaemia and hydrops fetalis, presenting at 35 wk gestation. Pregnancies affected by anti-C(w) merit closer scrutiny. Consideration should be given to performing more frequent antenatal ultrasound assessments to detect hydrops fetalis. This may help to support the need for more invasive procedures (cordocentesis and intrauterine transfusions).

ERIK, a low‐frequency red cell antigen of the MNS blood group system associated with Sta

A new low-frequency red cell antigen, ERIK (MNS37), is associated with the Sta antigen of the MNS system. Four ERIK+ propositi have been identified: all are St(a+). Thirteen other St(a+) samples, including one of the Mz type, and over 200 St(a-) samples were ERIK-. In two of the propositi ERIK is associated with an abnormal trypsin-resistant M antigen; in the others it is associated with N, which is shown to be expressed weakly in one family. Immunoblotting with an antibody to an epitope common to glycophorin A (GPA) and glycophorin B (GPB) gave identical results with St(a+) ERIK+ and St(a+) ERIK- cells, revealing GPA, GPB, an abnormal structure GPSta and aggregates of these components. In the propositi with trypsin-resistant M, GPSta carries the unusual M antigen, whereas in the M-N+ERIK+ individual analysed by immunoblotting GPSta carries N. Immunoblotting with anti-Sta and anti-ERIK showed that Sta is located on GPSta but that ERIK is located on GPA, presumably the GPA molecule encoded by the GYPA gene contiguous to the gene encoding GPSta.

SHIN, a low frequency red cell antigen, found in two Japanese blood donors.

A low frequency red cell antigen, SHIN, was detected in two Japanese blood donors. Red cells of the first propositus reacted, in pretransfusion tests, with the serum of a previously untransfused male patient. The second propositus was disclosed when anti-SHIN was used to screen red cells from 3,000 random blood donors in Tokyo: a frequency of 0.03% in this population. Family studies showed SHIN to be inherited as an autosomal dominant character and not to be part of the MNS, FY, JK or P1 blood group systems. Anti-SHIN is not a common antibody in normal sera but was found in about 10% of multispecific sera used in investigation of low frequency antigens.

Haemolytic Disease of the Newborn Probably due to Anti-ELO, an Antibody to a Low Frequency Red Cell Antigen

Investigation of mild bilirubinaemia and a positive direct antiglobulin test in a 2 day old baby revealed that the mother’s serum contained an antibody against the low frequency antigen ELO, which was present on the father’s red cells. Family studies showed that the ELO antigen segregates from Rh, Gc, ADA and PGM(1). The ELO antigen is enzyme resistant and therefore not likely to be part of the MNS or Duffy systems. No abnormalities were detected in immu- noblotting studies. Although insufficient samples were available to attempt elution of the antibody from the cord cells, it is probable that this case represents the first reported haemolytic disease of the newborn due to anti-ELO.

Kg, a New Low-Frequency Red Cell Antigen Responsible for Hemolytic Disease of the Newborn

Kg, a New Low-Frequency Red Cell Antigen Responsible for Hemolytic Disease of the Newborn

A new low-frequency antigen BOW (Bowyer).

BOW is a 'new' low-frequency red-cell antigen, detected in 2 unrelated English blood donors, that is sensitive to alpha-chymotrypsin and pronase. Anti-BOW is present in many polyspecific reagents used to define low-frequency antigens. Red-cell groups of the proposita, R.B., and her family show that the BOW blood group segregates independently from the ABO, Rh, MNSs, P1 and Kell blood group systems.

Two examples of a new low-frequency red cell antigen, JFV.

A new low frequency red cell antigen JFV has been found in two families, one of German and one of Dutch origin. JFV is inherited as an autosomal dominant character. Family studies showed that JFV is not controlled by the Rh, MNS, Lu, Fy, or Jk loci and that it is not X- or Y-borne.

Two Examples of a New Low-Frequency Red Cell Antigen, JFV

A new low frequency red cell antigen JFV has been found in two families, one of German and one of Dutch origin. JFV is inherited as an autosomal dominant character. Family studies showed that JFV is not controlled by the Rh, MNS, Lu, Fy, or Jk loci and that it is not X- or Y-borne.

The NFLD antigen in Japan.

The low-frequency red cell antigen NFLD was identified in 2 Japanese donors. A family study showed that the antigen is not part of the P1 blood group system. Anti-NFLD was found in serum of several donors (frequency of 0.044%).

RASM, a ‘New’ Low‐Frequency Blood Group Antigen

A 'new' low-frequency red cell antigen, RASM, was found in 3 generations of a Caucasian family. It is inherited as a Mendelian dominant character. The propositus, a newborn, had a positive direct antiglobulin test; overt haemolytic disease of the newborn was not present.

OSa, a 'new' low-frequency red cell antigen.

A new low-frequency red cell antigen, OSa, in a Japanese blood donor is inherited as a Mendelian dominant. A family study showed that OSa is not controlled by ABO, P1, Rh, Kidd, or Diego loci, nor is the antigen X- or Y-borne.