AIM: To prepare and characterize a novel anti-human CD83 monoclonal mAb. METHODS: Female BALB/c mice of 6-8 weeks old were immunized with CD83 transfectant (L929/CD83) as immunogen. The spleen B cells of the mice were fused with Sp2/0 myeloma cells. The hybridoma cells were screened with CD83 transfectant (L929/CD83 and 293/CD83) by FCM. The biological characteristics of antibody were investigated by rapid isotyping analysis, karyotype analysis, competitive inhibition test and Western blot. RESULTS: One hybridoma cell line named 9D8 was obtained, which had the property of secreting antihuman CD83 monoclonal antibody steadily, This mAb specifically recognized CD83 molecule expressed on human mature DC, activated T cells, and tumor cell line Daudi, myeloma cell line 8226. This mAb can recognize a distinct epitope from comercial mAb(HB15e). CONCLUSION: One hybndoma cell line has been developed successfully, which may lay a fundation for further study on the function of this molecule.

AIM: To prepare and characterize a mouse anti-human CD40 mutant monoclonal mAb. METHODS: Female BALB/c mice of 6-8 weeks old were immunized with CD40 mutant transfectant (L929-CD40mu) as immunogen. The spleen B cells of the mice were fused with Sp2/0 myeloma cells. The hybridoma cells were screened with CD40 mutant transfectant (L929-CD40mu) by FCM. Faststrip analysis was performed to identify Ig subclass of this mAb. The epitope recognized by this mAb was detected by Bio-5C11 competitive assay. Western blot technique was adopted to identify the mAb. The proliferation of tumor cells in vitro was analyzed by MTT assay and apoptosis of tumor cells in vitro was analyzed by PI-annexin V assay. RESULTS: One hybridoma cell line named 10C5 was obtained, which had the property of secreting anti-human CD40 mutant monoclonal antibody continuously and steadily. This mAb specifically recognized human CD40 mutant molecule and induced the apoptosis of tumor cells in vitro. CONCLUSION: One hybridoma cell line which can secret a mouse anti-human CD40 mutant mAb has been prepared successfully. This mAb can inhibit the growth of tumor cells expressing CD40 mutant and induce their apoptosis in vitro.

Objective To evaluate clinical value of double contrast-enhanced ultrasonography(DCUS)in diagnosing gastric stromal tumors(GST). Methods The medical records of 26 patients with a histological diagnosis of GST were retrospectively reviewed. The correlation between DCUS features and pathological findings of the lesions was compared. Results Total 26 cases of GST were divided into low risk group( 16 cases) and high risk group (10 cases). The size,contour,liquefactive necrosis and enhancement distribution of lesions were markedly correlated with the pathobiologic behaviour of the tumor ( P ＜0.05). There was no significant difference in border and metastasis of lesions between two groups( P ＞0.05). It was shown that DCUS supplied statistically significant improvement in the localization diagnosis and detection of liquefactive necrosis versus oral contrast-enhanced ultrasonography ( P ＜ 0.05 ). Conclusions DCUS is considered as a valuable tool in diagnosing location as well as pathobiological behaviour of GST. It can provide the guidance and reference comments for treatment algorithms.