[Study on RHCE genotyping of Rh blood group in Uygur nationality of Xinjiang in China].

This study was aimed to investigate the characteristics of RHCE genotyping of Xinjiang Uygur nationality population in China. Primers for detecting RHCE genes were designed according to the references, 89 Uygur nationality RhD-negative samples, 233 Han nationality RhD-negative samples and 109 Han nationality RhD-positive samples were detected by sequence-specific primer-polymerase chain reaction (SSP-PCR) for RHCE genotyping. All above-mentioned samples were unrelated. The results indicated that RHE/e genotyping results were consistent with the serological test results in the samples of Uygur and Han nationality, regardless of the RhD-negative samples or the RhD-positive samples. The RHC/c genotyping results from 89 RhD-negative samples of Uygur nationality were consistent with serological test results. However, total error of RHC/c genotyping from 233 RhD-negative and 109 RhD-positive samples of Han nationality was 5.05%. In conclusion, this method of RHCE genotyping is suitable for the analysis of the RHE/e genotyping of Uygur nationality, no erroneous RHC/c genotyping of Uygur nationality was found in this study, but this method needs to be further studied.

[Comparison between genotyping and serological phenotyping in RhCE blood group].

OBJECTIVE: To genotype the RHCE gene of Hans, Xinjiang's Uigurs and Kazakstans in China, and to compare the results of RHCE genotyping with that of RhCc/Ee phenotyping. METHODS: RHCE genes of 98 Hans with RhD positive and 230 Hans, 72 Uigurs and 18 Kazakstans with RhD/RHD negative were genotyped with PCR-sequence specific primer (SSP) technique. RESULTS: The results of RHE/RHe genotyping from samples with RhD positive and negative were in accord with that of phenotyping. It would result in 4.44% error using C-->G polymorphism at nt48 of RHCE gene to genotype RHCE, and 4.05% failure of detection using the 109 bp insertion to detectRHCE gene in Chinese Hans. The results of RHE/RHe genotyping in unrelated 72 Uigurs and 18 Kazakstans with RhD phenotype were consistent with that of phenotyping, and false positive and false negative were not found in genotyping in Uigurs and Kazakstans tested. CONCLUSION: The results of RHE/RHe and RHc genotyping were correct with PCR-SSP and accordant with that of phenotyping. Using the C48G polymorphism in exon 1 of RHCE to genotype RHC gene would result in false positive resulting from RHc mutation at this locus, and using the 109 bp insertion to genotype RHC gene would result in false negative because of the absence of the 109 bp. Therefore it is necessary to genotype RHC gene using more than two polymorphic loci.

[Investigation of the characteristics of Rh blood group of Uygur nationality in Xinjiang].

The study was to investigate the characteristics of Rh blood group of Uygur nationality in Xinjiang. 1 230 blood samples of Uygur nationality were studied by Rh serological typing, modified antiglobulin test, chloroform/trichloroethylene absorption elution test, upstream, downstream and hybrid Rhesus boxes, 10 exons of D gene, RHD(psi) pseudogene. The results showed that the frequency of RHD negative was 5.8%, and no Del type was found. The further investigation of 72 samples of RhD (-) found that ccee (57.02%) and Ccee (29.08%) phenotype as well as RHD(-)/RHD(-) genotype (94.44%) and complete deletion type of D gene exon (91.12%) were all in high frequency, no RHD(psi) pseudugene was detected. In conclusion, the Rh blood group of Uygurs nationality in Xinjiang possesses both oriental and caucasian Rh characteristics, which enriches the diversity of blood types in chinesenation.

[A comparative research on RHD gene structures of Chinese Han and Uigur population].

OBJECTIVE: To research comparatively on the RHD gene structures in unrelated RhD negative individuals of Chinese Uigur and Han population. METHODS: The upstream, downstream, hybrid box and 10 exons of RHD gene were detected with sequence specific primer-PCR technique. RESULTS: The results showed the genotypes of RhD negative individuals to have the significant difference between Chinese Uigur and Han population, that 94.44% Uigur individuals were with RHD(-)/RHD(-) genotype but just 61.40% Han population were with this genotype(94.44% versus 61.40%, P<0.01); 2.78% Uigur individuals were with RHD(+)/RHD(-) genotype but 34.21% Han population were with this genotype(2.78% versus 34.21%, P<0.01). However, there was significantly no RHD(+)/RHD(+) genotype difference between Chinese Uigur and Han population(2.78% versus 4.39%, P>0.05). In 78 cases of RhD negative Chinese Hans with single RHD gene, of which the RHD gene structure showed that 53(67.95%) cases were RHD(1-10) allele(of 53 RHD(1-10) alleles, 14 alleles were unexpressed); 15(19.23%) were RHD-CE(2-9)-D(2) allele; 5(6.41%) cases were RHD-CE(2-7)-D(2) allele; 2(2.56%) were similar to RHD-CE(3-6)D allele; 1(1.28%) case was RHD-CE(5-6)-D allele; and 2(2.56%) were RHD-CE(6)-D or point mutation respectively. Of 2 RhD negative Chinese Uigurs with RhD(-)/RHD(+) genotype, one carried RHD(1-10) allele, another carried RHD-CE(2-9)-D(2) allele. CONCLUSION: The most frequently unexpressed RHD alleles were RHD-CE(2-9)-D(2), RHD(1-10) and RHD-CE(2-7)-D(2) respectively in Chinese Han population who carried single RHD allele with RHD(-) phenotype and RHD(+) genotype. It showed the confluent character of RH gene in Chinese Han and Uigur population that there existed unexpressed RHD-CE(2-9)-D(2) allele in Chinese Uigur nationality, which was infrequent in Chinese Uigur population but frequent in Chinese Han population.

[Comparison of Rhesus boxes in Hans and Uighurs].

OBJECTIVE: To study the difference and similarity between Hans and Uighurs in regard to Rhesus box and its significance. METHODS: The sequence specific primers of upstream, downstream and hybrid Rhesus boxes were designed on the basis of RHD gene sequence. The upstream, downstream and hybrid Rhesus boxes were determined by polymerase chain reaction-sequence specific primer(PCP-SSP) and mismatched PCR. RESULTS: The percentage of RHD-/RHD-, RHD+/RHD- and RHD+/RHD+ genotypes ascertained in the unrelated Hans with RhD(-) were 61.40%, 34.21% and 4.39% respectively, while those in the unrelated Chinese Uighurs with RhD(-) were 94.44%, 2.78% and 2.78% respectively. Furthermore, all 6 cases of some other minorities were RHD-/RHD- types. The percentage of RHD-/RHD- and RHD+/RHD- genotypes ascertained in the unrelated Chinese Uighurs were significantly higher than those in Chinese Hans (P < 0.01), whereas no statistically significant difference in the percentage of RHD+/RDH+ genotype between the two groups was observed (P > 0.05). CONCLUSION: The Rh blood group of Uighurs in Xingjiang possesses both Oriental and Caucasian characteristics, which embodies a special ethnical aspect of the Chinese nation and is in accord with the anthropologic research results.

[Study on detection of samples of Rh-weak D and Del].

To study the detection of weak D and Del from samples initially screened RhD(-), RhD phenotype was initially screened by routine serological test, out of which weak D phenotype was detected by indirect antiglobulin test (IAT) and Del phenotype was detected by chloroform-trichloroethylene absorption-elution test. The results showed that 56 samples were RhD(-) confirmed by routine serology test, which were screened out of 26 200 donors, among them 5 samples were typed as weak D by IAT and 9 cases samples were typed as Del by absorption-elution test. In conclusion, the samples which typed as RhD(-) by routine serological test must be identified by IAT and chloroform-trchloroethylene absorption test is order to detect weak D and Del phenotype. It is important for clinical transfusion safely.

[Determination of human RHD gene rhesus box and its significance].

The aim was to determine RHD zygosity, further to investigate genetic structure of RHD gene, and to predict hemolytic disease of newborn (HDN). The upstream box, downstream box, and hybrid box of RHD gene were determined by PCR-SSP with 4 primers under the same conditions. The results showed that only hybrid box could be determined in RHD(-)/RHD(-) homozygosity. All the upstream box, downstream box, and hybrid box could be determined in RHD(+)/RHD(-) heterozygosity, while upstream box and downstream box except hybrid box could be determined in RHD(+)/RHD(+) homozygosity. Out of 50 cases of RhD(+), 5 cases (10%) were RHD(+)/RHD(-) heterozygosity, and the others (90%) were RHD(+)/RHD(+) homozygosity. 54 cases (55.1%), 36 cases (36.7%) and 8 cases (8.2%) were RHD(-)/RHD(-) homozygosity, RHD(+)/RHD(-) heterozygosity, and RHD(+)/RHD(+) homozygosity respectively in 98 unrelated cases of RhD(-) Chinese Hans. 2 cases of weak D were proved to be RHD(+)/RHD(-) heterozygosity. Out of 16 D(el) types, the upstream box, downstream box, and hybrid box could be determined in 10 cases (37.5%) and the upstream box and downstream box except hybrid box could be determined in 6 cases. Results detecting of RHD 10 exons in above samples proved the correctness of the method. It is concluded that the method is suitable for clinical application with its simplicity and veracity. There are many noneffective RHD genes (44.9%) in Chinese Hans with RhD(-) phenotype.

Ex vivo expansion of T, NK and CD34+ cells from umbilical cord blood.

Umbilical cord blood stem cell transplantation (CBSCT) has made significant progress in treatment of lethal congenital or malignant disorders. Both the incidence and severity of GVHD from CBSCT were lower than that from bone marrow and peripheral blood stem cell transplantation, particularly for adult patients, but these advantages were also associated with higher rates of relapse. The immune-mediated effect of natural killer and cytotoxic T cells against residual tumor cells were shown to prevent relapse and to induce remission after bone marrow transplantation. To explore possibility of ex vivo expansion of T, NK and CD34(+) cells from umbilical cord blood, cord blood was expanded ex vivo with different combinations of cytokines, T and NK cells proliferation and differentiation were observed. CB MNCs were separated in Ficoll-Isopaque column and cultured in IMDM for 14 days with different recombinant cytokines. Cultured cells were collected and analyzed for progenitor/stem cell immunophenotyping at day 0, 3, 7, and 14 by using flow cytometry. The results indicated that all test groups cultured with different combinations of SCF, IL-3, IL-6, IL-7, IL-2 showed significant expansion of UCB MNC, compared with the group without cytokines. All test groups showed expansion effects on CD34(+) cells, CD34(+) percentage went up from 1.6% in fresh CB to the highest 11.9% in group D (SCF + IL-3, IL-6, IL-2). The CD34(+) cells peak displayed at day 7 of culture in group A and D, while in other two groups B and C appeared at day 14 of culture. The expansion multiple of CD34(+) cells in all test groups at day 7 of culture were from 10 to 50. The average value of CD3(+) T cell in fresh UCB was 18.7 +/- 4.3%, the CD3(+) T cells decreased sharply in the medium without any interleukin, while obvious increase were observed in the other test groups containing different combinations of cytokines. The maximal expansion multiple of CD3(+) T cells reached 2 times of the fresh UCB level. CD56(+) cells amounted to 3.6 +/- 1.9% of fresh UCB, CD56(+) cell number increased significantly only in medium containing IL-2. It is concluded that T cells, NK cells as well as stem/progenitor cells can be expanded in the same time from CB-MNC with the combinations of cytokines.

[A method for Rhesus box test].

To study the method for Rhesus box test and its significance, the sequence specific primers of upstream, downstream and hybrid Rhesus boxes were designed according to RhD gene sequence; the upstream, downstream and hybrid Rhesus boxes were determined by PCP-SSP and mismatched PCR. The results showed that this method was confirmed by DNA Standard test. It was shown that in unrelative RhD positive individuals RHD(+)/RHD(-), RHD(+)/RHD(+) genotype accounted for 9.00%, 91.00% respectively, and in RhD negative individuals RHD(+)/RHD(-), RHD(+)/RHD(+), RHD(-)/RHD(-) genotype were 26.14%, 3.92%, 69.94% respectively. It is concluded that the method of Rhesus box test was confirmed to be reliable and can be used for the identification of RhD haplotype gene structure, as well as for study on inheritance, clinical transfusion and neonatal hemolytic diseases.

[Method of detection of soluble HLA-I and soluble HLA-I level alteration in storage blood].

Aim of this study was to develop the detection method of soluble human leukocyte antigens I (sHLA-I) and to explore sHLA-I level alteration in storage blood and its significance. sHLA-I level in sera of 60 Guangdong normal individuals and sHLA-I concentration in blood components from 20 donors quantitatively were detected by sandwich ELISA. The results showed that sensitivity of this assay was 2.84 ng/ml. Coefficients of variation were 5.80% within assays and 9.00% between assays respectively. The recovery rate was >/= 98.57%. The sHLA-I level of normal individuals in Guangdong was (699.54 +/- 360.10) ng/ml. sHLA-I in red blood cells stored for 28 days and in random-donor platelets were significantly higher than that in other blood components and their amount was proportionate to the number of residual donor leukocytes and to the length of storage. In conclusion, sandwich ELISA assay for detection of sHLA-I is a sensitive, specific and stable technique. Blood components with different concentration of sHLA-I may be chosen for clinical transfusion.

[Exon polymorphism of human RHD gene].

OBJECTIVE: To study exon polymorphism of human RHD gene and investigate the genetic mechanism of RhD-negative individuals. METHODS: PCR using sequence-specific primers (PCR-SSP) was performed on 40 RhD-positive, 120 RhD-negative and 2 weak D blood samples. RESULTS: All 10 exons could be detected in the 40 RhD-positive and 2 weak D samples. Out of the 120 RhD-negative samples, 28 (23.33%) carried 10 exons, 19 (15.83%) lost most of the 10 exons (with mainly intermediate deletion), and 73 (60.83%) had deletion of all the 10 exons; 19 samples of Del phenotype identified from the 120 RhD-negative samples had all the 10 exons. CONCLUSION: Polymorphism of the exon structure of RHD gene is present in RhD-negative individuals, characterized chiefly by gross deletion, partial deletion and non-deletion.

[ABO blood group typing for infants and its application for clinical transfusion].

To study the correct method for determining ABO blood types in infants and its influencing factors, blood types of 33 infants under 6 months old were determined by routine serological method, micro-column gel typing system and PCR-SSP genotyping method. Of the 33 cases with discrepant results of ABO blood type by different methods, the blood types of 32 cases were discrepant between red cell and serological typings in the routine serological method, and a false coincidence in 1 case was caused by bacterial infection resulting in B-like antigen. Correct blood typing was obtained in 27 cases with a correct rate of 84.4% (27/32) by using micro-column gel typing system. PCR-SSP method gave correct results in all of 33 cases. There was a significant difference between the results of micro-column gel typing system and PCR-SSP. It is concluded that to determine ABO blood type for infants < 6 months old, it is recommended to adopt micro-column gel typing system method, and what must be taken into account is the possible false coincidence caused by bacterial infection resulting in B-like antigen. In micro-column gel typing system, if the results of red cell and serological typing are identical, the principle is that blood transfusion must be performed with same ABO blood type between recipient and donor. If not, washed O red blood cells should be used for infants, and then change to transfusion with identical blood group according to PCR-SSP typing results.

[Methoxypolyethylene glycol-modified HLA-A2 antigen on lymphocytes].

OBJECTIVE: To modify the HLA-A2 antigen on the lymphocytes with methoxypolyethylene glycol (mPEG) so as to block the specific binding site for antibody. METHOD: Different types of mPEG (all with final concentration of 12 mmol/L) were used at different temperatures in PBS with varied pH values for the modification of the HLA-A2 antigen. RESULT: The modification of the antigen was not obviously affected when it was carried out at 4 degrees Celsius or room temperature, but higher temperatures of 30 and 37 degrees Celsius significantly hampered the modification. Better antigen modification was observed with high-concentration mPEG in basic PBS, depending also on the type of mPEGs used for this purpose. CONCLUSION: The specific HLA-A2 binding on the lymphocytes is completely blocked by benzotriazole carbonate-mPEG(mPEG-BTC), which is superior to N-hydroxysuccinimidyl ester of mPEG(mPEG-SPA). Maleimide-mPEG(mPEG-MAL) is incapable of blocking the HLA-A2 ligand-binding site with antibody.

[Camouflage of HLA-I antigen in lymphocyte surface].

The objective of this study was to investigate the method and effect of blocking the specific reaction between lymphocyte HLA-I antigen and its antibody. The lymphocytes were disposed with 12 mmol/L methoxypolyethelene glycol benzotriazol carbonate (mPEG-BTC) in concentration gradient in PBS (pH 7.4) at 22 degrees C. The effect of the modified lymphocytes was detected by microlymphocytotoxicity assay. The results showed that lymphocytes modified by mPEG-BTC did not react with related HLA-I antibodies in microcytotoxicity test. It is suggested that the specific reaction between HLA-I antigen of lymphocyte and HLA-I antibodies can be completely camouflaged by mPEG-BTC in PBS (pH 7.4) under 22 degrees C room temperature.

[Observation on gene polymorphism of Rh blood group in Chinese Han nationality].

To observe the gene polymorphism of Rh blood group in unrelated random individuals and families for Chinese Han nationality, polymerase chain reaction-sequence specific primer (PCR-SSP) was used to amplify the Rh C/E gene, RhD gene, exons, intron 2 and 10, insert and Rh Box in 160 blood samples of RhD positive unrelated individuals and 71 samples of RhD negative unrelated individuals and 7 samples of families whose probands were RhD-negative. The results showed that RhD genes of RhD-negative individuals with C antigens were polymorphism, three forms were found for D exon including intact, partial deletion and complete deletion exons. Insert fragments and Rh Box were found in most cases of families whose probands were RhD-negative and its inheritance accorded with the Mendel's Law, and it did not affect the expression of RhD gene. "Normal" RhD exon 4 amplifying product was not found in all of the samples. It was concluded that gene structure of the RhD-negative in Chinese was polymorphism, intact, partial deletion and complete deletion exons were found in the individuals with C antigen and probably existed specific D (nf) Ce haplotype. The function of insert was uncertain. The Rh gene sequences of Chinese Han nationality are different from those of Caucasian and the Rh gene library based on Han nationality should be established.