A survey of the incidence of Miltenberger antibodies among Hong Kong Chinese blood donors.

BACKGROUND: The ready availability of red cells of the Miltenberger (Mi) class III phenotype (6.28%) prompted the study of Mi antibodies among Chinese blood donors in Hong Kong, 98 percent of whom are descended from inhabitants of Guangdong Province in southern China. STUDY DESIGN AND METHODS: Red cells of the Mi class III phenotype were used to conduct a survey of the frequency of Miltenberger antibodies in 56,161 random Chinese blood donors, over a period of 12 months, using a microplate technique. RESULTS: Sera from 32 donors (0.057%) were found to contain Mi antibodies: sera from 22 contained anti-Mur + Hut; sera from 4 contained anti-Vw + Mur + Hut; sera from 4 had monospecific anti-Mur; and sera from 2 had monospecific anti-Hil. The immunoglobulin isotypes of 24 sera were mixtures of IgM and IgG, 4 were pure IgM, and 4 were pure IgG. CONCLUSION: The majority of Mi antibodies detected were naturally occurring. This survey proved useful for mass screening of random donors for the procurement of valuable Mi antisera.

Bv: a distinct category of B sub-group among Chinese blood donors in Hong Kong.

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.

The diagnostic value and patient acceptability of outpatient endometrial sampling with Gynoscann.

Endometrial sampling with Gynoscann was performed in the outpatient department in 70 women with abnormal vaginal bleeding prior to dilatation and curettage (D&C). Successful endometrial sampling was achieved in 62 (89%) patients; Of the samples obtained 44 (71.0%) were adequate for cytological assessment and 46 (74.2%) for histological assessment, compared to 80% of D&C samples being adequate for histological examination. In those patients in whom outpatient endometrial sampling was adequate, both the cytological and histological diagnosis agreed with the D&C. The outpatient endometrial sampling was well tolerated by the patients since the majority (89%) experienced either no or little pain. Vaginal bleeding following the procedure was minimal in all except 1 patient. Endometrial sampling with Gynoscann may be useful for endometrial assessment prior to commencement of hormonal therapy and hysterectomy. It is a potentially useful screening test for early detection of endometrial cancer in patients at risk.

The MiIII phenotype among Chinese donors in Hong Kong: immunochemical and serological studies.

The incidence of the MiIII phenotype among Chinese blood donors in Hong Kong was found to be 6.28%. Eleven individuals apparently homozygous for the MiIII gene were detected by immunoblotting with monoclonal antibodies R1.3 and R18. R1.3 detects an identical epitope on both glycophorins A and B and R18 detects a different epitope on glycophorin A. Immunoblotting with R1.3 showed an absence of bands corresponding to normal glycophorin B. Immunoblotting with R18 showed an absence of a 58 K band, which corresponds to a heterodimer of normal glycophorin B complexing with the MiIII component, found in MiIII heterozygotes. In two families with apparent MiIII homozygous individuals, both parents of the propositi had the MiIII phenotype which implies normal autosomal inheritance of the MiIII gene. In another family, only one parent had the MiIII phenotype and the presence of an Su gene is postulated to explain the immunochemical and serological findings.