[Affected Factors of Separating Erythrocytes by Discontinuous of Density Gradient Centrifugation].

OBJECTIVE: To study the affected factors of the separation of red blood cells by discontinuous density gradient method, and to establish the optimal operating conditions of percoll for the separation of erythrocytes. METHODS: The osmolality of different ratio of Percoll and 1.5 mol/L NaCl were 9:1, 10:1, 11:1, 12:1, 13:1 ratio, was detected respectively. The isotonic osmolality ratio was selected as optimum stock isotonic Percoll solution(SIP). Evaluation criteria: All the different density cells were separated sufficiently by centrifugation, there is little red cell retention and entrainment phenomena. The separation efficacy of different red cell suspension concentration, different centrifugal force, different centrifugal speed, different temperature and different time were compared. RESULTS: The separation efficacy of red cell suspension concentration which not exceed 50% was better than above 50%, efficacy of 4 000×g was superior to 3 000×g and 2 000×g, 2-8 centrifugal acceleration and deceleration centrifugal could obtain the satisfactory efficacy, the 4 °C layered effect was more stable than room temperature, the separation effect of 20 min was better than 15 min and 10 min. CONCLUSION: Percoll and 1.5 mol/L NaCl 12:1 to 11:1 can be used as stock isotonic percoll solution, preferentially selected 4 °C as centrifugal conditions. When conditions of separation was satisfied, the centrifugal acceleration and deceleration is 2-8, the optimal centrifugal effect can be obtained with the decrease of erythrocyte suspension concentration, with centrifugation time prolonging and centrifugal force increasing.

[Anti-A/B Antibody Titers in Group O Healthy Donors in Hainan Province Area].

OBJECTIVE: To detect the IgM anti-A (B) and IgG anti-A (B) antibody titers of group O healthy donors in Hainan province area, to understand the distribution of O-type blood donor IgM and IgG antibody titers and to analyze the relationship between antibody titers, so as to provide experimental evidences for the safety and feasibility of urgent transfusion of uncrossmatched group O RBCs. METHODS: Group O whole blood sample was collected from 80 volunteers blood donors. IgM antibody titrations was performed using the immediate spin (IS) tube, and IgG antibody titration were performed using the column agglutination technique with anti-human globulin (AHG). Using two-way ANOVA, paired t-test and correlation analysis, the different types of antibodies were compared. RESULTS: The IgM antibody titers distributed in 4-1 024, IgG antibody titer distributed in 2-2 048. Anti-A antibody titers of IgG were significantly higher than that of IgM anti-B, IgG anti-B and IgM anti-A titers (P < 0.05). There was a positive correlation bewteen IgM anti-A and anti-B, IgM anti-B and IgG anti-B, IgG anti-A and anti-B (P < 0.05). CONCLUSION: Group O blood donors have high antibody titers in Hainan province area, type O RBC suspensions should be first screened through screening the anti-A titer of IgG, so that can significantly improve the pass rate of O-type universal blood and reduce testing costs.