Rapid assay of phage-derived recombinant human fabs as bispecific antibodies.
Specific anti-tumor and anti-viral activities can be conferred on lymphocytic and myeloid effector cells by retargeting them with bispecific antibodies. These are antibodies which possess an anti-target binding region and a region capable of binding specific effector cell surface markers. For the rapid evaluation of recombinant human Fabs as bispecific antibodies, we have constructed a vector that allows for the conversion of Fabs into protein A fusion proteins. These can be used to generate bispecific antibodies when complexed to appropriate anti-effector cell immunoglobulins. As a model system, a protein A fusion derivative of a human recombinant anti-herpes simplex virus (HSV) Fab was constructed and complexed to OKT3, a T cell-activating antibody specific for CD3. This complex reduced HSV-2 yields in infected cells by about three logs relative to controls when incubated on HSV-2-infected cell monolayers in the presence of IL-2-activated lymphocytes. The system described allows for the rapid evaluation of recombinant human Fabs as bispecific antibodies for therapeutic applications. In addition, Fab-protein A fusion proteins can be used in ELISA and other immuno-assays with increased sensitivity.
Sanna
P P
PP
Department of Neuropharmacology, Scripps Research Institute, La Jolla, CA 92037, USA. psanna@pluto.scripps.edu
De Logu
A
A
Williamson
R A
RA
Samson
M E
ME
Altieri
D C
DC
Bloom
F E
FE
Burton
D R
DR
D018033:Antibodies, Bispecific / Q000032:analysis* / Q000235:genetics; D000914:Antibodies, Viral / Q000032:analysis* / Q000235:genetics; D005822:Genetic Vectors; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000032:analysis* / Q000235:genetics; D008213:Lymphocyte Activation; D010957:Plasmids / Q000235:genetics; D011993:Recombinant Fusion Proteins; D018139:Simplexvirus / Q000276:immunology; D013205:Staphylococcal Protein A / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology
D018033:Antibodies, Bispecific; D000914:Antibodies, Viral; D007140:Immunoglobulin Fab Fragments; D011993:Recombinant Fusion Proteins; D013205:Staphylococcal Protein A