Induction of CD40 Expression and Enhancement of Monoclonal Antibody Production on Murine B Cell Hybridomas by Cross-Linking of IgG Receptors
详细信息 查看全文
- 作者：Alicia Martí ; n-Ló ; pez ; Francisco Garcí ; a-Camacho ; El Hassan Belarbi ; Sergio Martí ; nez-Escobar ; Antonio Contreras-Gó ; mez ; Emilio Molina-Grima
- 刊名：Biotechnology Progress
- 出版年：2007
- 出版时间：April 2007
- 年：2007
- 卷：23
- 期：2
- 页码：452 - 457
- 全文大小：158K
- 年卷期：v.23,no.2(April 2007)
- ISSN：1520-6033
文摘
The 55-6 murine B cell hybridoma line not constitutively expressing CD40 was treated withincreasing amounts of intact anti-mouse surface immunoglobulin G antibody (anti-mIgG) eithernot preincubated or preincubated for 48 h with lipopolysaccharide (LPS). In vitro, cross-linkingof surface immunoglobulin G (sIgG) with the whole molecule of anti-IgG antibodies inducedthe expression of CD69, CD40, and CD19 surface antigens on 55-6 cells. The effect of sIgGligation was dose-dependent, and preincubation with LPS enhanced their responsiveness to anti-mIgG stimulation. The expression of these surface molecules reached the maximum valueduring the first part of the cell cycle, corresponding to the position of the G1 peak of the DNAdistribution. Stimulation of cells with anti-mIgG did not induce changes either in the numberof viable cells or in the fraction of cells undergoing proliferation (mitosis). However,preincubation of 55-6 cells with LPS for 48 h before stimulation with anti-mIgG increased boththe maximum specific growth rate (
max) and the percentage of cells in the G2/M phase, incomparison with non-preincubated cells. Moreover, on cells preincubated with LPS prior toanti-mIgG treatment, specific IgG2a production rate was enhanced significantly compared tothat obtained in control cultures. The correlation between the antibody production rate and theamount of IgG that is detectable on the cell surface was analyzed by flow cytometry. A goodcorrelation between secreted and surface IgG was observed, and the results of cell cycle analysesdemostrated that the 55-6 hybridoma cell line has a substantially higher sIgG content in G1phase.
max) and the percentage of cells in the G2/M phase, incomparison with non-preincubated cells. Moreover, on cells preincubated with LPS prior toanti-mIgG treatment, specific IgG2a production rate was enhanced significantly compared tothat obtained in control cultures. The correlation between the antibody production rate and theamount of IgG that is detectable on the cell surface was analyzed by flow cytometry. A goodcorrelation between secreted and surface IgG was observed, and the results of cell cycle analysesdemostrated that the 55-6 hybridoma cell line has a substantially higher sIgG content in G1phase.