Membrane immunoglobulin expressed by retroviral vector gene transfer mimics partial function of the B-cell receptor in vivo.
Activation of B-cells is initiated by the ligation of B-cell receptors by its cognate antigen, inducing a series of signal cascades. Understanding the molecular mechanisms of these important events is a crucial goal for immunologists. Chimeric B cell receptors provide a powerful tool for analysis of B-cell signal function. However, this method can only be used in tool cells, but cannot be used for in vivo study. Here, we constructed a retroviral vector to encode both heavy chains and light chains of a membrane immunoglobulin, and expressed them in primary B-cells using retroviral gene transfer. Our results demonstrate that the membrane immunoglobulin expressed by retroviral vectors transfer can initiate B-cell receptor-mediated signaling, resulting in the phosphorylation of Syk and Erk1/2 proteins. The results showed that B-cells expressing membrane immunoglobulin can make proliferative responses to cognate antigen both in vitro and in vivo. Therefore, we provide a methodology for rapidly analyzing the downstream signals of B-cell receptors both in vitro and in vivo, which could expedite the identification of proteins involved in B-cell function.
State key Laboratory of Medical Molecular Biology, Department of Biochemistry & Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
Jing
J
Lu
State key Laboratory of Medical Molecular Biology, Department of Biochemistry & Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
Feng
F
Chen
State key Laboratory of Medical Molecular Biology, Department of Biochemistry & Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
Zhen
Z
Xu
State key Laboratory of Medical Molecular Biology, Department of Biochemistry & Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
Lingling
L
Zhang
State key Laboratory of Medical Molecular Biology, Department of Biochemistry & Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
Peng
P
Xu
State key Laboratory of Medical Molecular Biology, Department of Biochemistry & Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China. liudp@pumc.edu.cn.
Depei
D
Liu
State key Laboratory of Medical Molecular Biology, Department of Biochemistry & Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
Chihchuan
C
Liang
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D049109:Cell Proliferation; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D007136:Immunoglobulins / Q000235:genetics* / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D041681:NIH 3T3 Cells; D010766:Phosphorylation; D011947:Receptors, Antigen, B-Cell / Q000235:genetics* / Q000378:metabolism*; D012190:Retroviridae / Q000235:genetics; D015398:Signal Transduction
D007136:Immunoglobulins; D008565:Membrane Proteins; D011947:Receptors, Antigen, B-Cell; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins
BCR; membrane immunoglobulin; retroviral vector