[The influence of the FR-1 in heavy chain (VH) of antibodies on antibody secretion].
The N-terminal segment (FR-1) of the heavy chain (VH) of antibodies may have a great impact on IgG secretion in Escherichia coli and other hosts. Decrease in secretion may be caused by a single amino acid change in the framework region. To investigate the high antibody expression in mammalian cells, we designed the site-directed mutagenesis of the FR-I of the pCMV-RV/VH gene,which expressed the immunoglobulin heavy chain of human anti-Rabies virus antibody. Mutating Glu (H6) to Gln could improve both antibody secretion and affinity. The immunofluorescence assay indicated that both the secretion-deficient antibodies and the secretion- efficient antibodies could be transcribed and translated intracellularly, and led into ER,then transferred to Golgi apparatus,and the difference in secretion may relate to the contribution of the FR-I to the folding and assembly of the antibody. In this study, we have confirmed experimentally that the nature of residues H6 in antibody heavy chains indeed determines the antibody secretion in mammalian cells. These results also provide the basis for antibody production.
Zhu
Li-Li
LL
Viral Gastroenteritis Division,National Institute for Viral Disease Control and Prevention, State key Laboratory for Infectious Disease Control and Prevention, China CDC, Beijing 100052, China. julie811205@yahoo.com.cn
Li
Chuan
C
Li
Jian-Dong
JD
Sun
Li-Na
LN
Liang
Mi-Fang
MF
Li
De-Xin
DX
D000818:Animals; D000906:Antibodies / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D000914:Antibodies, Viral / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D000915:Antibody Affinity; D001692:Biological Transport; D019556:COS Cells; D002522:Chlorocebus aethiops; D003587:Cytomegalovirus / Q000235:genetics; D004721:Endoplasmic Reticulum / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000235:genetics / Q000276:immunology; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D007128:Immunoglobulin Fragments / Q000235:genetics / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D007135:Immunoglobulin Variable Region / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D016297:Mutagenesis, Site-Directed; D010957:Plasmids / Q000235:genetics; D011820:Rabies virus / Q000235:genetics / Q000276:immunology / Q000378:metabolism
D000906:Antibodies; D000914:Antibodies, Viral; D006023:Glycoproteins; D007128:Immunoglobulin Fragments; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region