Human monoclonal antibody inhibits Porphyromonas gingivalis hemagglutinin activity.
BACKGROUND
Porphyromonas gingivalis has been implicated as an important pathogen in the development of chronic periodontitis, and its colonization of subgingival sites is critical in the pathogenic process. One potential virulence factor, hemagglutinin, may mediate bacteria attachment onto and penetration into host cells, as well as agglutinate and lyse erythrocytes to intake heme, an absolute requirement for growth. We previously cloned the gene encoding the 130 kDa hemagglutinin domain (130k HMGD) and identified its functional domain. The construction of a human monoclonal antibody that is capable of inhibiting the hemagglutinating ability is significant and important toward the development of passive immunotherapy.


METHODS
Human lymphocytes isolated from a donor, who had high antibody titer against the recombinant 130k HMGD (r130k HMGD), were immortalized by Epstein-Barr virus, and specific antibody-producing B cells were established by panning using the r130k HMGD.


RESULTS
The constructed HuMAb-HMGD1, IgG subclass, recognized the r130k HMGD as well as the 43 and 49 kDa major bands in P. gingivalis cells and vesicles. The HuMAb-HMGD1 significantly inhibited hemagglutinating activity of P. gingivalis vesicles in a dose-dependent manner. Furthermore, the HuMAb-HMGD1 recognized the synthetic peptide, EGSNEFAPVQNLTGSSVG, which contains the functional domain of 130k HMGD.


CONCLUSIONS
The newly constructed HuMAb-HMGD1 may prove to be useful for the development of passive immunization against periodontal diseases caused by P. gingivalis infection, pending the results of fertility study in disease mode.
Kaizuka
Kouji
K
Department of Biochemistry, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
Hosogi
Yumiko
Y
Hayakawa
Mitsuo
M
Shibata
Yasuko
Y
Abiko
Yoshimitsu
Y
D018829:Adhesins, Bacterial / Q000235:genetics / Q000276:immunology*; D000907:Antibodies, Bacterial / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology / Q000821:virology; D001422:Bacterial Adhesion; D015153:Blotting, Western; D002908:Chronic Disease; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D005822:Genetic Vectors; D006388:Hemagglutinins / Q000235:genetics / Q000276:immunology*; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D015151:Immunoblotting; D007074:Immunoglobulin G / Q000145:classification / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology; D010518:Periodontitis / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D011994:Recombinant Proteins; D014774:Virulence
C117707:130k-HMGD protein, Porphyromonas gingivalis; D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D006388:Hemagglutinins; D007074:Immunoglobulin G; D011994:Recombinant Proteins