Expression of Rh Blood Group Gene Transcripts in Human Leukocytes

The Rh blood group system was recognized as one of the most complex polymorphisms in human. Whether or not the Rh antigens are present on human leukocytes is still an unresolved question. The expression of the Rh gene at the mRNA was analyzed in purified populations of human leukocytes by using reverse transcription and polymerase chain reaction (RT-PCR) followed by Southern blot analysis. The PCR products of the 5′-terminal region showed a single band as expected in the CD19+TCR-1− and CD14+ cells but doubtfully in the CD13+CD71− and CD19−TCR-1+ cells. On the other hand, in all these cells, the PCR products of the 3′ region exhibited multiple additional bands migrating ahead of the band as expected, which showed distinctly different sets of bands in each cell. The additional bands appeared to consist of RhPI- and RhPII-cDNA splicing isoforms. These results indicated that the expression of the Rh gene is not restricted to human erythroid lineage. Additionally, it was suggested that different transcription initiation sites might be utilized preferentially for Rh gene expression.