OBJECTIVETo establish a three-step purification method of preparative-scale antiCD20 (Fab')2 using AKTA prime.

METHODSAntiCD20 (Fab')2 was extracted by hyperosmotic solution and then purified by CM sepharose FF, phenyl sepharose FF, and protein G sepharose FF.

RESULTSAround 8 mg anti-CD20 (Fab')2, whose purification was 96.678%, was purified. The antigen-binding activity of antiCD20 (Fab')2 was similar to that of antiCD20 (Fab')2 purified by protein G sepharose FF and S-100.

CONCLUSIONThe three-step purification method can obtain high-purity preparative-scale antiCD20 (Fab')2 in a simple way.

Antibodies ; immunology ; isolation & purification ; Antigens, CD20 ; immunology ; Chromatography ; methods ; Humans ; Immunoglobulin Fab Fragments ; immunology ; isolation & purification

OBJECTIVE: To study cellular immune function of palatine tonsil B lymph cell. METHOD: The phenotype of palatine tonsil cells (PTC) and that of peripheral blood mononuclear cell (PBMC) were compared using fluorescence staining and flow cytometry (FCM) analysis, then immunomagnetic beads were used to separate CD3- cell in PTC and PBMC. The proliferation function of CD3- lymph cell of PTC and PBMC was tested after stimulated by CD20mAb. RESULT: FCM analysis founding that 71.2% PTC express CD20 with higher mean fluorescence intensity, MFI, compared to the 15.5% in PBMC. There's no significant difference between the proliferation of PTC and PBMC B lymph cell. CONCLUSION CD20 expression is different in PTC and PBMC, but corresponding function is still unknown.
Adult ; Antigens, CD20 ; metabolism ; B-Lymphocytes ; cytology ; immunology ; metabolism ; Flow Cytometry ; Humans ; Palatine Tonsil ; cytology ; immunology

Pemphigus is a life-threatening autoimmune blistering disease affecting the skin and mucosa. Patients with severe pemphigus require long-term treatment with corticosteroids and other immunosuppressive drugs, which can lead to serious adverse events. Rituximab, a monoclonal antibody directed against the CD20 antigen of B lymphocytes, has been demonstrated to be effective in recalcitrant and life-threatening pemphigus.
Antibodies, Monoclonal, Murine-Derived ; adverse effects ; therapeutic use ; Antigens, CD20 ; immunology ; Humans ; Pemphigus ; therapy ; Rituximab

After having successfully constructed and expressed the gene of the anti-CD3/anti-CD20 bispecific single-chain antibody (bscCD3 x CD20), here we analyzed its in vitro bioactivity of mediating the lysis of Ramous human B-lymphoma cells in the presence of T-enriched human peripheral blood lymphocytes (PBL). Obvious opoptosis characters were observed by Annexin V/PI(AV/PI) stained and scanning electron microscope. As evaluated by non-radioactive cytotoxity assay, the bscCD3 x CD20 showed potent bioactivity of mediating human B-lymphoma cells lysis in the presence of T-enriched human PBL. The potency of cytotoxicity depended on the ratios of effect cells to target cells (E:T) used. Further, the antibody showed a dose and time-dependent effect on mediating Ramous cells lysis. The specific lysis reached about 87.3% at an antibody concentration of 5microg/mL and E:T used at 10:1. Clear changes in apoptogenes expression profiles were detected by apoptosis gene array after Ramous cells were treated with the antibody and PBL. Among the upregulated apoptogenes, ATM and P53 showed an increase of 187 times and 15 times respectively, which suggested that ATM-p53 pathway may be the main apoptosis way of Ramous cells induced by T cells in the presence of the bscCD3 x CD20.
Antibodies, Bispecific ; immunology ; Antigens, CD20 ; immunology ; Apoptosis ; immunology ; CD3 Complex ; immunology ; Humans ; Lymphoma, B-Cell ; immunology ; pathology ; T-Lymphocytes, Cytotoxic ; immunology ; Tumor Cells, Cultured

Antibodies ; immunology ; therapeutic use ; Antigens, CD20 ; immunology ; Antilymphocyte Serum ; therapeutic use ; CD3 Complex ; immunology ; Diabetes Mellitus, Type 1 ; drug therapy ; immunology ; Humans ; Immunotherapy ; methods

Adult ; Antigens, CD20 ; metabolism ; Brain ; pathology ; Brain Neoplasms ; immunology ; pathology ; CD3 Complex ; metabolism ; Diagnosis, Differential ; Humans ; Leukocyte Common Antigens ; metabolism ; Lymphomatoid Granulomatosis ; immunology ; pathology ; Male

The biological activity of ADCC by anti-CD20 monoclonal antibody was determined by BioGlo™ Luciferase Assay System using Jurkat/NFAT-luc+FcγRIIIa cell line as effector cell and WIL2-S cell line as target cell. The developed method was verified for specificity, precision and accuracy. Anti-CD20 monoclonal antibody showed a dose-response mode by the developed method, and the determination result complied with the following four-parameter equation: y = (A-D)/[1 + (X/C)(B)] + D. The optimized parameters of the method were determined including the antibodies diluted concentration (18,000 ng·mL(-1)), dilution rate (1:5), the ratio of effector cell and target cell (6:1), and induction time (6 h). The values of eight independent tests have passed a statistical test for curve regression analysis, linear or parallelism, which showed the method possessed good specificity. Four different dilute groups of recovery rates sample were determined for 3 times, and the result showed mean relative potencies of (44.39±3.93)%, (72.74±2.78)%, (128.28±7.01)% and (168.19±2.70)% respectively, with a variation coefficient of less than 10%, and the recoveries of (88.78±7.85)%, (96.99±3.70)%, (102.63±5.61)% and (112.12±1.80)% respectively. A novel reporter gene method for determination of biological activity of ADCC by anti-CD20 monoclonal antibody was successfully developed, which showed strong specificity, good reproducibility and high accuracy, and might be used routinely.
Antibodies, Monoclonal, Murine-Derived ; pharmacology ; Antibody-Dependent Cell Cytotoxicity ; Antigens, CD20 ; immunology ; Genes, Reporter ; Humans ; Reproducibility of Results ; Rituximab

This study was aimed to investigate the effects of rituximab (RTX), a chimeric human anti-CD20 monoclonal antibody, on lymphoma cell injury induced by X ray irradiation. The human Burkitt EBV-infected and moderate radioresistance lymphoma cells (Namalwa) were used in the this study. Cytotoxicity of rituximab combined with X ray irradiation on Namalwa cells was measured by sulforhodamine B (SRB)-staining; the apoptosis of Namalwa cells was detected by flow cytometry with FITC-Annexin V/PI double staining; the morphologic changes of cells were observed under transmission electron microscope (TEM) and the change of intracellular free calcium level ([Ca(2+)]i) in response to irradiation and rituximab was determined by means of the fluorescent dye fluo-3 and confocal microscopy. The results showed that the growth inhibition in Namalwa cells exposed to irradiation was enhanced by treatment with rituximab. Compared with irradiation alone, rituximab combined with irradiation significantly induced the cell apoptosis and a sustained rise of intracellular free calcium ([Ca(2+)]i) level in Namalwa cells; the serial apoptotic appearances of cells could be observed under TEM. It is concluded that rituximab can enhance the sensitivity of lymphoma cells on X ray irradiation as to induce cell more apoptosis, in this process the intracellular free calcium ([Ca(2+)]i), as an intracellular signaling molecule probably plays an important role.
Antibodies, Monoclonal, Murine-Derived ; immunology ; pharmacology ; Antigens, CD20 ; immunology ; Apoptosis ; Calcium ; analysis ; Cell Line, Tumor ; Humans ; Lymphoma ; drug therapy ; metabolism ; pathology ; Radiation Tolerance ; drug effects ; Rituximab

Primary renal lymphoma (PRL) is very rare. In order to investigate the clinical features, diagnosis, therapy and prognosis of PRL, three cases of primary renal lymphoma diagnosed definitely and treated in our hospital in the recent ten years were reported, and their clinical features, laboratory examination, pathological observation and their therapeutics were analyzed. The results indicated that the three cases of primary renal lymphoma were all male elders. Their most common symptoms were flank pain along with abdominal mass and hematuria, etc. Because of suspicion of cancer with renal involvement, the three patients all underwent laparotomy. Histological examination showed diffuse B-cell lymphoma in the three cases, and the immunophenotype was CD20 positive in all three cases. These cases were treated with combined therapeutics, including rituximab, intermittent interferon and local radiotherapy. The 2 out of 3 cases lived for more than 5 years after therapy. In conclusion, as PRL is especially rare, and often diagnosed mistakenly, it is suggested that early and definite diagnosis and individualization of treatment for PRL patients may be possible to achieve a better therapeutic result.
Aged ; Aged, 80 and over ; Antigens, CD20 ; analysis ; Humans ; Kidney Neoplasms ; diagnosis ; immunology ; therapy ; Lymphoma, B-Cell ; diagnosis ; immunology ; therapy ; Male ; Middle Aged ; Prognosis

BACKGROUND: Bone marrow biopsies are routinely performed for staging patients with B-cell non-Hodgkin lymphoma (NHL). In addition to histomorphological studies, ancillary tools may be needed for accurate diagnosis. We investigated the clinical utility of multiparameter flow cytometric examination of bone marrow aspirates. METHODS: A total of 248 bone marrow specimens from 232 patients diagnosed with B-cell NHL were examined. Monoclonal antibodies directed against CD19, CD20, CD10 (or CD5), and kappa and lambda immunoglobulins were used. Multi-stage sequential gating was performed to select specific cells of interest, and the results were compared with bone marrow histology. RESULTS: The concordance rate between histomorphology and flow cytometry was 91.5% (n=227). Eight cases (3.2%) were detected by flow cytometry alone and were missed by histomorphology analysis, and 6 of these 8 cases showed minimal bone marrow involvement (0.09-2.2%). The diagnosis in these cases included large cell lymphoma (n=3), mantle cell lymphoma (n=3), and mucosa-associated lymphoid tissue (MALT) lymphoma (n=2). Thirteen cases were histopathologically positive and immunophenotypically negative, and the diagnoses in these cases included diffuse large cell lymphoma (n=7), T-cell/histiocyte-rich large B-cell lymphoma (n=2), anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma (n=1), follicular lymphoma (n=1), MALT lymphoma (n=1), and unclassifiable lymphoma (n=1). CONCLUSIONS: Multi-color flow cytometry can be a useful method for assessing bone marrow in staging NHL and also plays a complementary role, especially in detecting small numbers of lymphoma cells.
Antibodies, Monoclonal/immunology ; Antigens, CD19/immunology/metabolism ; Antigens, CD20/immunology/metabolism ; Bone Marrow/*pathology ; Female ; Flow Cytometry ; Humans ; Immunophenotyping ; Lymphoma, B-Cell/*pathology ; Male ; Neoplasm Staging ; Neprilysin/immunology/metabolism