Then, we have investigated whether the 20mer D393-CD20 peptide spanning the splicing site might be targeted by the immune system and we have shown that D393-CD20-specific CD4 Th1 clones could directly recognize malignant B cell lines and kill autologous lymphoma B cells indicating that D393-CD20-derived epitopes are naturally processed and presented on tumor cells.
We have identified a spliced mRNA transcript of CD20 (named D393-CD20) which was associated with resistance to RTX in primary B cell from patients with lymphoma and leukaemia.
Combining a CD20 chimeric antigen receptor and an inducible caspase 9 suicide switch to improve the efficacy and safety of T cell adoptive immunotherapy for lymphoma.
Anti-CD20 IgA can protect mice against lymphoma development: evaluation of the direct impact of IgA and cytotoxic effector recruitment on CD20 target cells.
However, the activation of innate effector cells using a TLR3 agonist that did not activate B10 cells overcame the negative regulatory effects of endogenous B10 cells and enhanced lymphoma depletion during CD20 immunotherapy in vivo.
The study showed that lymphoma xenografts could be targeted in the presence of endogenous biotin when anti-CD20 fusion proteins containing SAv mutants (scFv(4)-SAv-S45A or scFv(4)-SAv-Y43A) were employed in combination with CA 2 and [(111)In]4b.
Combination treatment with 4-1BBL/anti-CD20 fusion protein and anti-CD3/anti-CD20 diabody led to significantly increased T-cell cytotoxicity to human B-lymphoma cells in vitro and drastically more potent tumor inhibitory activity in vivo in xenografted B-cell lymphoma in severe combined immunodeficiency disease mice.
Measles virus (MV)-PNP H(blind)antiCD20 is a CD20-targeted and prodrug convertase-armed MV that temporarily controls growth of lymphoma xenografts in severe combined immunodeficiency (SCID) mice in combination with fludarabine phosphate (fludarabine).
Fusion proteins had reduced IFNalpha activity in vitro compared with native IFNalpha, but CD20 targeting permitted efficient antiproliferative and proapoptotic effects against an aggressive rituximab-insensitive human CD20(+) murine lymphoma (38C13-huCD20) and a human B-cell lymphoma (Daudi).
Treatment of patients with relapsed or refractory low grade follicular B-NHL lymphoma with rituximab (chimeric anti-CD20 mAb) has resulted in approximately 50% response rate.
The recombinant antibodies were detected in the milk of transgenic mice with the highest expression level up to 17 microg/mul and could specifically bind the CD20 surface antigens on human B-lymphoma cells.
The anti-CD20 monoclonal antibody rituximab has been less successful in treating chronic lymphocytic leukemia (CLL) than lymphoma, possibly due to the lower density of CD20 on B lymphocytes from CLL patients than on those from lymphoma patients.
Importantly, in contrast to parental NK-92, CD20-specific NK cells efficiently lysed CD20 expressing but otherwise NK-resistant established and primary lymphoma and leukemia cells, demonstrating that this strategy can overcome NK-cell resistance and might be suitable for the development of effective cell-based therapeutics for the treatment of B-cell malignancies.
We have established a CD20- lymphoma cell line, RRBL1, from a diffuse large B-cell lymphoma with CD20- transformation from CD20+ follicular lymphoma after treatment with rituximab.