B_v: a distinct category of B sub‐group among Chinese blood donors in Hong Kong

Abstract

During the period 1984-1989, a total of 46 examples of Bv phenotype were encountered out of a total of 567,210 donors, giving an incidence of 1 in 12,330 among the Chinese in Hong Kong. The Bv determinant corresponds to the portion of the B antigen that is present on rabbit red cells, and gives a negative reaction with polyclonal anti-B reagents absorbed with rabbit red cells that still react with B3. Some potent monoclonal anti-B reagents confirm the absence of a B epitope from Bv red cells even by adsorption and elution techniques. The failure of some monoclonal anti-B reagents to detect Bv demonstrates the need to select or blend monoclonal anti-B reagents for use in typing Oriental bloods. Cell-conversion techniques failed to convert O cells to B cells using Bv serum with the appropriate substrate, whereas sera from most of the other B variants were capable of doing so. The Bv phenotype, therefore, represents a distinct category of B subgroups that is easily distinguishable from B3 and other B variants.

A novel blood group B subgroup: serological and genetic studies

“…In the second study, an exhaustive adsorption was tried with the same monoclonal reagent and the remaining anti‐B activity after each adsorption (3 h, overnight and 48 h at 4 °C, respectively) was tested against adsorbing red cells. The last adsorption study was employed for examining the presence of the B v phenotype, as described by Mak et al . (1992).…”

The A1 (B) phenomenon: a monoclonal anti‐B (BS‐85) demonstrates low levels of B determinants on A1 red cells

“…papain-treated A1 red cells, but react well with sub groups of B (B3, B, and Bin,) (Mak et al, 1992: this issue) were used to demonstrate that the three strong AI (B) reactive A1 samples, used for the H status and transferase studies, were not examples of AIBw of known weak B sub-groups (Table 8), although absolute exclusion of weak B sub-groups is difficult to establish because of A1 (B) reactivity. Detailed studies of the A and H transferase enzyme levels were made on the plasma of three strong saline test Al (B) reactive AI blood samples, and 37 control Al blood samples (some 1-day and other 6-days-old) that were not A1 (B) reactive in saline tests.…”

ABO, H, and Lewis Systems

“…An inherited variant B antigen called B v was characterised by the failure of B v red cells to react with human anti -B reagents that had been adsorbed with rabbit red cells [348,349] . B v red cells and secretions appear to lack normal human B antigen, but contain a B -like determinant, possibly the non -fucosylated B -like antigen on rabbit red cells (the ' Galili antigen ' [350] ).…”

“…B v red cells and secretions appear to lack normal human B antigen, but contain a B -like determinant, possibly the non -fucosylated B -like antigen on rabbit red cells (the ' Galili antigen ' [350] ). Among 567 210 Hong Kong Chinese blood donors, 46 examples of B v and eight examples of AB v were found [349] . Among 567 210 Hong Kong Chinese blood donors, 46 examples of B v and eight examples of AB v were found [349] .…”