Juan Gu1, An-Yuan Sun2, Xue-Dong Wang1, Chao-Peng Shao3, Zheng Li4, Li-Hua Huang1, Zhao-Lin Pan1, Qing-Ping Wang5, Guang-Ming Sun6. 1. Department of Clinical Laboratory, The Fifth People's Hospital of Wuxi, Affiliated Hospital of Nanjing Medical University, Wuxi, Jiangsu, People's Republic of China. 2. Department of Clinical Laboratory, The Affiliated Provincial Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China. 3. Shenzhen Blood Center and Institute of Blood Transfusion Medicine, Shenzhen, Guangdong, People's Republic of China. 4. Department of Clinical Laboratory, The Affiliated Hospital of Guilin Medical College, Guilin, Guangxi, People's Republic of China. 5. Department of Clinical Laboratory, The Fifth People's Hospital of Wuxi, Affiliated Hospital of Nanjing Medical University, Wuxi, Jiangsu, People's Republic of China Department of Clinical Laboratory, the Shaoxing Hospital of China Medical University and Central Hospital of Shaoxing County, Shaoxing, Zhejiang, People's Republic of China. 6. Zhenjiang Maternal & Children Health Care Hospital, The Fourth Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China.
Abstract
BACKGROUND: The characteristics of the D antigen are important as they influence the immunogenicity of D variant cells. Several studies on antigenic sites have been reported in normal D positive, weak D and partial D cases, including a comprehensive analysis of DEL types in Caucasians. The aim of this study was to assess D antigen density and epitopes on the erythrocyte surface of Asian type DEL phenotypic individuals carrying the RHD1227A allele in the Chinese population. MATERIALS AND METHODS: A total of 154 DEL phenotypic individuals carrying the RHD1227A allele were identified through adsorption and elution tests and polymerase chain reaction analysis with sequence-specific primers in the Chinese population. D antigen density on the erythrocyte surface of these individuals was detected using a flow cytometric method. An erythrocyte sample with known D antigen density was used as a standard. Blood samples from D-negative and D-positive individuals were used as controls. In addition, D antigen epitopes on the erythrocyte surface of DEL individuals carrying the RHD1227A allele were investigated with 18 monoclonal anti-D antibodies specific for different D antigen epitopes. RESULTS: The means of the median fluorescence intensity of D antigen on the erythrocyte membrane surface of D-negative, D-positive and DEL individuals were 2.14±0.25, 193.61±11.43 and 2.45±0.82, respectively. The DEL samples were estimated to have approximately 22 D antigens per cell. The samples from all 154 DEL individuals reacted positively with 18 monoclonal anti-D antibodies specific for different D antigen epitopes. DISCUSSION: In this study, D antigen density on the erythrocyte surface of DEL individuals carrying the RHD1227A allele was extremely low, there being only very few antigenic molecules per cell, but the D antigen epitopes were grossly complete.
BACKGROUND: The characteristics of the D antigen are important as they influence the immunogenicity of D variant cells. Several studies on antigenic sites have been reported in normal D positive, weak D and partial D cases, including a comprehensive analysis of DEL types in Caucasians. The aim of this study was to assess D antigen density and epitopes on the erythrocyte surface of Asian type DEL phenotypic individuals carrying the RHD1227A allele in the Chinese population. MATERIALS AND METHODS: A total of 154 DEL phenotypic individuals carrying the RHD1227A allele were identified through adsorption and elution tests and polymerase chain reaction analysis with sequence-specific primers in the Chinese population. D antigen density on the erythrocyte surface of these individuals was detected using a flow cytometric method. An erythrocyte sample with known D antigen density was used as a standard. Blood samples from D-negative and D-positive individuals were used as controls. In addition, D antigen epitopes on the erythrocyte surface of DEL individuals carrying the RHD1227A allele were investigated with 18 monoclonal anti-D antibodies specific for different D antigen epitopes. RESULTS: The means of the median fluorescence intensity of D antigen on the erythrocyte membrane surface of D-negative, D-positive and DEL individuals were 2.14±0.25, 193.61±11.43 and 2.45±0.82, respectively. The DEL samples were estimated to have approximately 22 D antigens per cell. The samples from all 154 DEL individuals reacted positively with 18 monoclonal anti-D antibodies specific for different D antigen epitopes. DISCUSSION: In this study, D antigen density on the erythrocyte surface of DEL individuals carrying the RHD1227A allele was extremely low, there being only very few antigenic molecules per cell, but the D antigen epitopes were grossly complete.
Authors: F F Wagner; A Frohmajer; B Ladewig; N I Eicher; C B Lonicer; T H Müller; M H Siegel; W A Flegel Journal: Blood Date: 2000-04-15 Impact factor: 22.113
Authors: E A Beckers; B H Faas; P Ligthart; M A Overbeeke; A E von dem Borne; C E van der Schoot; D J van Rhenen Journal: Transfusion Date: 1997-06 Impact factor: 3.157