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Non-Hodgkin’s lymphoma（NHL）is a malignant tumor that occurs in the lymphoid system and is a common and high incidence rate malignant tumor which seriously threatens human health.Antibody drugs targeting CD20 are one of the effective means to treat NHL in clinic.It kills tumor cells by inducing apoptosis and immune functional activity mediated by FC fragment of antibody,such as complement dependent cytotoxicity（CDC）and antibody dependent cytotoxicity（ADCC）.However,antibody drugs have the problems of low drug efficacy,drug resistance and high treatment cost.Enhancing the immune function of anti-CD20antibody can improve the anti-tumor activity and therapeutic window.At present,the enhancement of ADCC and CDC functions of antibodies mainly depends on the FC transformation of antibodies by genetic technology.Such methods have a large workload in screening mutation points of receptors and are difficult to use computer aided design.This thesis takes rituximab（RTX）as the research object,drawing on the antibody recruitment strategy and the multivalent effect in glycobiology.Designed and synthesized multivalent rhamnose-RTX antibody recruitment complex through host-guest self-assembly or covalent modification and proposes to recruit a large number of anti-Rha antibodies existing in human serum or produced by pre-immunization to the surface of tumor cells.The Fc fragment of anti-Rha antibody is further combined with effector cells or complement to enhance the immune activity of antibody ADCC and CDC to improve the antitumor activity of the original antibody by non-genetic engineering technology.The main results are as follows:（1）By using host-guest assembly strategy,28 valent rhamnose-RTX antibody recruitment complex（ARC）was constructed to enhance the CDC activity of RTX.RTX-Ad A4（Ad A:adamantane）conjugate with Dar=4 was prepared based on disulfide bridging method.Flow cytometry showed that RTX retained the ability to recognize tumor cells with high expression of CD20 antigen after coupling with 4 Ad As and its specificity and binding ability were not affected.Modified with 7-valent rhamnoseβ-Cyclodextrin（β-CD-PEG-Rha7）interacted with adamantane to form rhamnose-RTX antibody recruiting complex on the surface of tumor cells.Its ability to recruit anti-Rha antibody and its mediated CDC immune activity were evaluated.The cytotoxicity of ARC2 in vitro was evaluated.It was found that in the presence of anti-Rha antibody,the lysis ability of ARC2 to Ramos cell line was significantly enhanced and the EC50value was 0.013 nmol/L which was 60 times higher than RTX.（2）Using host-guest assembly strategy,a 56 valent rhamnose RTX antibody recruitment complex（ARC）was constructed to enhance the CDC activity of RTX.After the reduction of four pairs of disulfide bonds of RTX,eight sulfhydryl groups obtained and coupled with maleimide-PEGn-Ada（n=0,2,4）derivatives to obtain three RTX-Ad A8 conjugates with different PEG units and Dar=8.Flow cytometry analysis showed that after RTX connected 8ADAs the specificity and binding ability of targeted cells were not affected.Modified withβ-CD-PEG-Rha7 with host-guest assembly of cyclodextrin and adamantane and formed the 56-valent rhamnose-RTX antibody recruitment complexes.Their ability to recruit anti-Rha antibodies and mediated CDC immune activity was evaluated.The results showed that the ability of 56-valent rhamnose modified ARC to recruit rhamnose antibody was related to the length of PEG in the main molecular structure.The shorter length of PEG,the stronger ability to recruit antibody.For the ARCs formed by A2 and A3 with strong recruitment ability,in the presence of anti-Rha antibody,the killing EC50 value of Ramos cell line was 0.031 and 0.096nmol/L respectively,which was 109 and 35 times higher than RTX.Compared with the 28valent ARC we got in last the chapter,the CDC cytotoxicity of ARC formed by A2 was relatively increased for 1.8 times.（3）Referring to the antibody drug conjugate design strategy,using rhamnose modified maleimide derivatives and reduced disulfide of RTX to fixed-point coupling,an 8-valent Rha modified RTX was constructed to enhance the antitumor activities of CDC and ADCC.Maleimide derivatives modified by rhamnose were synthesized by chemical method and obtained SMCC-PEGn-Rha（n=0,2,5）then coupled with the 8 sulfhydryl groups.The rhamnose covalently modified RTX-PEGn-Rha8 conjugate R1～R3（R1:n=0;R2:n=2;R3:n=5）was obtained.Flow cytometry analysis showed that the binding EC50 of 8-valent rhamnose modified RTX conjugate R1～R3 to high expression CD20 tumor cells were 11.7,11.8 and 13.0nmol/L,respectively,which decreased slightly compared with unmodified RTX antibody;The determination of antibody recruitment ability showed that the ability of the conjugate to recruit anti-Rha antibody was closely related to the length of PEG in the linker.Conjugate R2 with PEG2 as linker showed the most efficient antibody recruitment ability.Evaluation of immune function in vitro and found that the immune function mediated by RTX-PEGn-Rha8 conjugate was closely related to the length of PEG and its antibody recruitment ability.Compared with unmodified RTX,the ADCC activity of conjugates R2 and R3 increased by 1.6 and 1.8 times,respectively;The corresponding CDC cytotoxicity evaluation showed that the conjugate R2with PEG2 as linker showed the strongest CDC activity.Its EC50 for three CD20 positive tumor cells（Raji,Ramos and jeko-1）were 0.11,0.068 and 2.19 nmol/L,respectively.Compared with unmodified RTX,the cytotoxicity of CDC was 150,186 and 51 times higher,respectively.In the animal model of tumor bearing mice,compared with RTX,conjugate R2 showed better antitumor effect,the average tumor weight decreased from 0.75 g to 0.31 g and the tumor inhibition rate was 58%enhanced;Histochemical staining of main organs showed that the conjugate R2 after rhamnosylation had no obvious cytotoxicity and had a certain safety in vivo.