Efficacy of plant-produced recombinant antibodies against HCG.
BACKGROUND
Antibody engineering facilitates the construction of different antibody formats [single chain variable fragment (scFv), diabody, full-size chimeric monoclonal antibody] with ease.


METHODS
We constructed recombinant antibodies against HCG, which is widely used in pregnancy testing and is also produced by a number of cancers.


RESULTS
The recombinant antibodies were transiently expressed in tobacco leaves to levels of up to 40 mg of pure protein per kg fresh leaf weight. Enzyme linked immunosorbent assay (ELISA) and electrophoretic mobility assay (EMSA) confirmed antibody specificity for the beta subunit of beta-HCG. The efficacy was confirmed by inhibiting HCG induced testosterone production by Leydig cells in vitro and by blocking the HCG induced increase in mouse uterine weight in vivo.


CONCLUSIONS
Passive immunization with recombinant HCG-specific antibodies may have clinical utility as (i) diagnostic and therapeutic tools for HCG-expressing cancers and (ii) contraceptive measures.
Kathuria
S
S
Department of Molecular Biotechnology, 52074 Aachen, Germany, Talwar Research Foundation, New Delhi 110068, India.
Sriraman
R
R
Nath
R
R
Sack
M
M
Pal
R
R
Artsaenko
O
O
Talwar
G P
GP
Fischer
R
R
Finnern
R
R
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis* / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology; D000917:Antibody Formation; D000918:Antibody Specificity; D001698:Biomedical Engineering / Q000379:methods; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000276:immunology* / Q000494:pharmacology; D004355:Drug Stability; D005260:Female; D007985:Leydig Cells / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009500:Neutralization Tests; D009929:Organ Size / Q000187:drug effects; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology; D013739:Testosterone / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D014026:Nicotiana / Q000276:immunology*; D014599:Uterus / Q000033:anatomy & histology
D000911:Antibodies, Monoclonal; D018997:Chorionic Gonadotropin, beta Subunit, Human; D011994:Recombinant Proteins; D013739:Testosterone