Introduction:

Rituximab, chimeric antibody specific for human CD20 molecule, has been widely used in the treatment of several B-cell linfoproliferative disorders. For the selection of patients with the greatest potential to benefit from the therapy with rituximab, a number of techniques using monoclonal antibodies have been developed to detect the CD20 molecule.

Objective:

To obtain and to characterize a mouse IgG1 recombinant antibody, specific for human CD20, that contains the variable regions of rituximab.

Methods:

The lentiviral transduction of human embryonic kidney cells (HEK293) was used for the stable expression of the recombinant antibody. The immunochemical characterization of the antibody was performed by Western Blot and the recognition of CD20 was evaluated by immunohistochemistry and flow cytometry.

Results:

We generated the antibody 1F5, able to recognize by flow cytometry the CD20 molecule expressed on lymphoid human cell lines, as well as peripheral blood mononuclear cells from healthy donors and patients with B-cell lymphoproliferative disorders. However, 1F5 antibody detected the CD20 molecule on fresh tissues, but not on formalin-fixed paraffin embedded tissues,by immunohistochemistry.

Conclusions:

This work suggests the potential use of 1F5 antibody for the measurement of CD20 expression by flow cytometry in patients with B-cell leukemias or B-cell lymphomas in phase of leukemization. This could complement the studies to ensure the appropriate selection of patients for the treatment with rituximab.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )