Objective:To investigate the role of the IgG subtypes (IgG1 and IgG2a) in anti-glycoprotein (GP) Ⅰbα antibody-induced platelet clearance.Methods:Venous blood was collected from healthy volunteers, and platelets were separated. The phagocytosis of human platelets by human acute monocytic leukemia cells (THP-1 cells) induced by different anti-GPⅠbα antibodies (AN51, AK2, HIP1, TM60, VM16d, WM23, and SZ2) was detected by flow cytometry. The effects of the AN51 full-length antibody, F (ab') 2, and Fab fragments on platelet phagocytosis by THP-1 cells were detected by flow cytometry. Then, the Fc blocking antibody 2.4G2 and normal rat IgG2a or IgG1 were injected into C57BL/6J mice via the posterior ocular vein, and their effects on platelet reduction induced by R300 were detected by a hematology analyzer. Results:Compared with IgG1, the IgG2a subtype of anti-GPⅠbα antibodies induced the phagocytosis of platelets by THP-1 cells in vitro ( P<0.05). In contrast to the AN51 full-length antibody, neither AN51 F (ab') 2 nor the Fab fragment could induce THP-1 cells to phagocytose platelets ( P<0.05). Compared with the control group, anti-mouse GPⅠbα R300-induced thrombocytopenia in mice was reduced at 2, 4, and 6 h after the injection of Fc blocking antibody 2.4G2 ( P<0.05). Similarly, R300-induced thrombocytopenia in mice was reduced at 2, 4, and 6 h after the injection of rat IgG2a ( P<0.05) . Conclusion:IgG2a plays an important role in anti-GPⅠbα-induced clearance.

Objective:To investigate the role of the IgG subtypes (IgG1 and IgG2a) in anti-glycoprotein (GP) Ⅰbα antibody-induced platelet clearance.Methods:Venous blood was collected from healthy volunteers, and platelets were separated. The phagocytosis of human platelets by human acute monocytic leukemia cells (THP-1 cells) induced by different anti-GPⅠbα antibodies (AN51, AK2, HIP1, TM60, VM16d, WM23, and SZ2) was detected by flow cytometry. The effects of the AN51 full-length antibody, F (ab') 2, and Fab fragments on platelet phagocytosis by THP-1 cells were detected by flow cytometry. Then, the Fc blocking antibody 2.4G2 and normal rat IgG2a or IgG1 were injected into C57BL/6J mice via the posterior ocular vein, and their effects on platelet reduction induced by R300 were detected by a hematology analyzer. Results:Compared with IgG1, the IgG2a subtype of anti-GPⅠbα antibodies induced the phagocytosis of platelets by THP-1 cells in vitro ( P<0.05). In contrast to the AN51 full-length antibody, neither AN51 F (ab') 2 nor the Fab fragment could induce THP-1 cells to phagocytose platelets ( P<0.05). Compared with the control group, anti-mouse GPⅠbα R300-induced thrombocytopenia in mice was reduced at 2, 4, and 6 h after the injection of Fc blocking antibody 2.4G2 ( P<0.05). Similarly, R300-induced thrombocytopenia in mice was reduced at 2, 4, and 6 h after the injection of rat IgG2a ( P<0.05) . Conclusion:IgG2a plays an important role in anti-GPⅠbα-induced clearance.

Forensic examination materials are often plagued by trace amounts,mixes,and other factors.Single-cell isolation technology can solve these forensic problems to some extent by studying each cell individually to obtain comprehensive and reliable information.There are many single cell isolation techniques available in research reports,such as flow cytometry,laser capture microdissection,etc.This review will summarize the most common single cell isolation techniques used by researchers today,and summarize the application of various techniques in forensic science,summarize the selection strategies for single-cell isolation techniques in different scenarios based on cost,degree of automation,yield,cell damage rate,and the availability of relevant forensic platforms,and finally explore the forensic application prospects of single-cell isolation techniques.In general,single cell isolation can be applied to multiple fields such as mixed stain examination,post-mortem time inference,pre-and post-mortem injury determination,forensic toxicology analysis,forensic microbiology and forensic anthropology.The development of single cell isolation technology is of great value to the application of forensic medicine,and will provide a new way of deciphering difficult examination materials.