Objective    To identify monoclonal antibodies against human heparanase and to screen a monoclonal antibody specifically inhibiting tumor metastasis.     Methods    Through Western blotting

three self-prepared monoclonal antibodies (No. 7

No. 11

and No. 12) were subjected to heparanase specificity identification and screening with total proteins of HepG2

SGC-7901

MKN45

SW480

U2OS and MCF-7 cells as samples. Immunocytochemical assay was

used to further verify the specificity of the screened antibody. Transwell cell invasion assay

in vitro

was used to observe the inhibitory effect of the screened antibody on tumor metastasis.     Results    All the three monoclonal antibodies could bind heparanase in different tumor cells. Monoclonal antibody No. 12

as well as a commercial anti-heparanase monoclonal antibody as positive control

could detect weak positive expression of heparanase in MCF-7 cells

indicating the best specificity. Immunocytochemical assay results showed that monoclonal antibody No. 12 could detect positive heparanase expression in SGC-7901

HepG2

MKN45

SW480 and U2OS cells

and weak positive heparanase expression in MCF-7 cells. Transwell cell invasion assay results demonstrated that the migrated cell numbers of SGC-7901

HepG2

MKN45

SW480 and U2OS cells treated by monoclonal antibody No. 12 (100 μg

1 mg/ml approximately) for 48 h were significantly lowered as compared with those treated by normal mouse IgG for 48 h (

P

<

0.05).     Conclusion    A self-prepared monoclonal antibody can specifically bind heparanase in tumor cells and inhibit the invasion and metastasis of tumor cells by suppressing heparanase activity.