ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00249.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.The unfolding story of genes encoding variant glycophorin molecules is already known to be more complicated than described here. The principles outlined provide a basis for understanding the fundamental events that occur in genes encoding the glyco‐phorins as well as genes encoding unrelated proteins carrying other blood group antigens. Over 20 different genes involving theGYPAandGYPBfamily have been described. These genes arise from gene rearrangements within a relatively short region. This hot spot of activity has inverted palindromic sequences, which are known to be sites for DNA recombination. Similar structures exist in the major histocompatibility complex (MHC) where allelic diversity is a functional requisite. However, the significance of allelic diversity in the glycophorin gene family is not understood. TheGYPA, GYPBandGYPEgene cluster is known to be prone to mutation by radiation because there is a high incidence of somatic mutation events in atomic bomb survivors, in people exposed to accidental radiation, in patients with Bloom's syndrome and in patients receiving radiation therapy. The mutation events were dose dependent: the greater the exposure, the greater proportion of red blood cells exhibited mutations. While it is known that MHC diversity protects against infection, the reason for glycophorin rearrangements remains to be determine

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00250.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.The aim of this study was to compare the socio‐demographic characteristics and risk factors in anti‐HCV positive blood donors with those of matched controls. The participants were 50 hepatitis C antibody (HCV) positive blood donors and 50 matched blood donors with no evidence of HCV infection, who gave blood to the South Western Transfusion Centre between November 1991 and July 1992. A confidential structured interview was conducted to collect socio‐demographic data and to elicit information on risk factors for HCV. Measurements were made of the prevalence of risk factors and socio‐demographic characteristics in cases and controls.The main results were that 45 of the 50 cases could have been exposed to HCV by previous intravenous drug abuse (IVDA), blood transfusion or medical employment. Cases were significantly more likely to have a history of IVDA, tattooing or of medical employment than matched controls. Cases with no history of IVDA were significantly more likely to have had a blood transfusion.The key conclusions to emerge are that current policies are ineffective at excluding those with a history of IVDA from the donor pool. Consideration should be given to the introduction of a policy of direct confidential questioning about risk factors for all donors, or, at a minimum, the use of a questi

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00251.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.All blood donors in Scotland who were found to be infected with hepatitis C virus (HCV) in the first 6 months of routine testing of all donations for anti‐HCV were contacted. Those who attended were counselled, a history of exposure to risk was sought, and blood was taken for alanine aminotransferase (ALT) level as a measure of liver function. The epidemiological features were then correlated with the virological findings and ALT.In the period under study between September 1991 and February 1992, 180658 blood donors attended. The prevalence of HCV infection was 0.088%. Of the 151 donors who attended for counselling, 101 (68%) were male. Intravenous drug use was the most common risk activity (39%), followed by previous blood transfusion (15.2%), other parenteral exposure (11.2%) and heterosexual contact with a parenterally infected partner (8.6%); 29.1% of donors gave no history of possible exposure.Elevated ALT levels were found in 59%. ALT levels were higher in donors with HCV types 1 and 3 than in HCV type 2 or non‐viraemic donors.The prevalence of HCV in Scottish blood donors is thus relatively low. This may relate to the effectiveness of donor selection procedures, but donors with risk activities which should debar them continue to donate. The combination of ALT and PCR appears to be useful in counselling and assessing infected don

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00252.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.In the U.K., blood donations have been routinely screened for anti‐HCV since September 1991. In order to get the most epidemiological benefit from these extensive screening data, the histories obtained at counselling from donors confirmed to be anti‐HCV positive, ‘indeterminate’ and falsely positive have been analysed in detail. In addition, the associations with potential risk factors have been investigated by comparing these groups of donors with a control group of 771 routine donors bled on one day during the study, at North London Blood Transfusion Centre. This paper documents the prevalence and demography of HCV infection in asymptomatic blood donors, to assess varicus possible sources of infection and the association between liver function test results and alcohol consumption in donors. One in 1400 previously untested donors was confirmed positive for anti‐HCV. Age (the group 30–49 years being highest), tattooing and intravenous drug use in both sexes, ear‐piercing in males and blood transfusion in females were all significantly associated with an increased risk of HCV infection. Intravenous drug use proved to be the factor most strongly associated with risk. Liver function tests (alanine aminotransferase) were elevated in a significant number of donors confirmed to be anti‐HCV positive but no clear correlation between alanine aminotransferase level and either time since infection or alcohol consumption was found. Alcohol consumption was significantly higher in donors confirmed to be anti‐HCV positive and was particularly marked in those admitting to previous intravenous drug use. Although donors confirmed to be anti‐HCV positive had a 5–10 times greater chance of non‐Caucasian ethnic origin compared with controls, the association with ethnic origin was not as marked as it was fo

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00253.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.Autologous collections are strongly advocated by the New South Wales Red Cross Blood Transfusion Service (BTS) and have increased more than sevenfold since 1988. Directed donations, although not promoted, have also increased during this time. The prevalence of infectious disease markers (HIV, hepatitis C, hepatitis B and syphilis) in donations collected by the BTS from different donor groups including overall volunteer homologous, first‐time volunteer homologous, autologous and directed were evaluated over a 42‐month period. Donations from first‐time volunteer homologous donors had the highest prevalence of hepatitis B and C. Autologous donations had a significantly higher prevalence of hepatitis B, hepatitis C and syphilis compared with overall volunteer homologous donations. The percentage of directed donations testing positive for either hepatitis B or C was higher than overall volunteer homologous donations, but not statistically significant. This study demonstrates that donations from first‐time donors are the least safe, that the crossover of autologous blood into the volunteer homologous pool decreases the safety of that pool and suggests that directed donations may not be as safe as volunteer homologous donations and cannot be generally advocated at th

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00254.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.The normal and variant forms of GPC and GPD molecules carry antigens of the Gerbich blood group system. This blood group system comprises three high‐incidence antigens (Ge2, Ge3 and Ge4) and four low‐incidence antigens (Wb, Lsa, Dhaand Ana). Erythrocytes of the Ge and Yus phenotypes lack normal GPC and GPD molecules but express variant molecules (denoted GPC.Ge, GPC.Yus, respectively) that functionally substitute for normal GPC and GPD in the membrane. Leach phenotype cells lack GPC and GPD molecules and are elliptocytic in shape with a membrane that is less deformable than that of normal cells. The Lsaantigen is expressed on higher molecular‐weight variants of GPC (GPC.Lsa) and GPD (GPD.L3a). Wb, Dhaand Anaantigens arise from point mutations in theGYPCgene and are expressed on GPC.Wb, GPC.Dhaand GPD.Ana, respectively. The structure of each of the variant GPC and GPD molecules and the location of the Gerbich blood group system antigens is discussed. TheGYPCgene, located on chromosome 2q14‐q21, is 13.5 kb long and comprises four exons. Exons 1,2 and most of exon 3 encode theN‐terminal extracellular domain while the remainder of exon 3 and exon 4 encode transmembrane and cytoplasmic domains of GPC. Exons 2 and 3 are highly homologous, with less than 5% nucleotide divergence. The molecular basis of generation of variation GPC and GPD molecules, and the structure of theGYPCgene from different Leach phenotype individuals, is

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00255.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.Six new murine monoclonal antibodies (mAbs) directed to the erythrocyte membrane glycophorins C (GPC) and D (GPD) were obtained from splenocytes of different BALB/c mice immunized with human red blood cells, and fully characterized. The mAbs were selected by agglutination tests with control and Gerbich‐negative cells, and by immunoblotting analysis. They showed specificity for the N‐terminal domain(s) of GPC (and GPD) and were classified into three categories by competitive analysis using125Ilabelled antibodies and real‐time biospecific interaction. The first group (NaM10‐7G11, NaM70‐1G4 and NaM77‐7B6) compete for epitope(s) located at the N‐terminal portion of GPC. Agglutination‐inhibition tests revealed that the 7G11 epitope involves the amino group of Met1and sialic acid residue(s) whereas the 1G4 and 7B6 epitopes contain O‐glycans. NaM89‐2G11 belongs to a second group; its epitope is located in a region including Glu17, Asp19and (an) O‐glycan(s). The third group comprises mAbs NaM19‐3C4 and NaM98‐3Cl which bind to both GPC and GPD in proximity of the binding site of human anti‐Ge:3 antibodies.In addition, mAb 3C4 (anti‐GPC/GPD) was found to bind to approximately 125 000 sites per red cell. Considering that the ratio of the GPC to GPD is about 3–4 to 1, the number of GPC and GPD molecules was estimated as

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00256.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.This report presents the results of two National Workshop exercises which were designed to evaluate interlaboratory and interassay variation in sensitivity of techniques used for the detection of platelet‐reactive alloantibodies. Most workshop participants used the platelet immunofluorescence test. Sensitivity of this assay was improved when fluorescence was measured by flow cytometer rather than by microscope. The MAIPA assay was found to be highly sensitive but required considerable technical expertise, and the choice of antiglycoprotein II/IIIa (CD61/41) monoclonal antibody was found to have a significant effect on its ability to detect anti‐HPA

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00257.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SUMMARY.There are no current U.K. or international guidelines or regulations covering the production, processing and storage of haemopoietic cells such as to allow their engraftment following myeloablative therapy. This paper seeks to provide such guidelines. It enumerates how quality control and assurance can be applied to this area of transfusion medicine; procedural steps relating to bone marrow harvest on peripheral blood stem cell collection are outlined and recommended doses of nucleated cells suggested for both procedures. General specifications for identification, storage and transportation of bone marrow and peripheral blood stem cells are included and specific laboratory procedures related to the provision of haemopoietic cells for engraftment are outlined. Umbilical cord blood transplants and long‐term bone marrow culture are alluded to but these are still in a research phas

ISSN:0958-7578    

DOI:10.1111/j.1365-3148.1994.tb00258.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY