Alloanti-c in a c-positive, JAL-positive patient.
OBJECTIVE
In the Rh blood group system, partial D, C, and e antigens are well-known, but a partial c antigen resulting in the production of alloanti-c in a c+ individual is rare. One example of an alloanti-c in a c+ person was an anti-Rh26, which can appear as anti-c, and another was an alloanti-c in a c+ person with a presumed R(1)r phenotype. The finding of an apparent alloanti-c in a transfused c+ patient initiated this investigation.


METHODS
Haemagglutination tests, DNA extraction, polymerase chain reaction (PCR)-based assays (PCR-restriction fragment length polymorphism, allele-specific PCR), reticulocyte mRNA extraction, reverse transcriptase (RT)-PCR and sequencing were performed by standard procedures.


RESULTS
Plasma from a 64-year-old African American woman with a wound infection following a mastectomy contained anti-E, anti-S, anti-K, anti-Fy(a) and anti-Jk(b), reacting by the indirect antiglobulin test. In addition, the patient's plasma gave reactions that were consistent with an anti-c, while her pre-transfusion red blood cells typed c+ with some anti-c reagents. These results are consistent with a partial c antigen. The patient's red blood cells also typed V+(W)VS- and JAL+. Analyses of DNA and Rh-transcripts from this patient showed the presence of the following genes: RHD*D, RHD*DAU0, RHCE*Ce and RHCE*ce(S)(340).


CONCLUSIONS
The nucleotide 340C>T change in RHCE exon 3 (predicted to encode 114Trp) of the RHCE*ce(S)(340) allele is associated with a JAL+ phenotype and the altered expression of the c, V and VS antigens. This alteration in the c antigen allowed the patient to make an alloanti-c. This case reveals that the RHCE*ce(S)(340) allele encodes a partial c antigen.
Ong
J
J
Blood Centers of the Pacific, San Francisco, CA, USA.
Walker
P S
PS
Schmulbach
E
E
Storry
J R
JR
Vege
S
S
Westhoff
C
C
Lomas-Francis
C
C
Reid
M E
ME
D017707:Erythrocyte Transfusion; D005091:Exons; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D007518:Isoantibodies / Q000097:blood* / Q000235:genetics; D008875:Middle Aged; D020125:Mutation, Missense; D012204:Rh-Hr Blood-Group System / Q000097:blood* / Q000235:genetics*; D013530:Surgical Wound Infection / Q000097:blood / Q000235:genetics / Q000628:therapy
D007518:Isoantibodies; C066468:RHCE protein, human; D012204:Rh-Hr Blood-Group System