Generation of ctl lines with specificity against multiple tumor antigens or multiple viruses

Abstract

The present invention encompasses methods and compositions for the generation and use of cytotoxic T lymphocytes that target multiple viruses or that are specific for multiple tumor antigens. In specific embodiments, the generation methods employ use of certain cytokines to promote proliferation and reduce cell death in an activated T cell population and / or that employ a particular bioreactor having a gas permeable membrane.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation application of U.S. patent application Ser. No. 12 / 862,409, filed Aug. 24, 2010, which claims priority to U.S. Provisional Patent Application Ser. No. 61 / 236,261, filed Aug. 24, 2009, both of which applications are incorporated by reference herein in their entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]This invention was made with government support under P50 CA126752 awarded by NIH-NCI. The government has certain rights in the invention.TECHNICAL FIELD[0003]The present invention generally concerns the fields of cell biology, immunology, molecular biology, and medicine. In particular embodiments, the invention generally concerns immunotherapy for cancer.BACKGROUND OF THE INVENTION[0004]Multivirus-Specific T Cells for Prevention and / or Treatment of Viral Infections in the Immunocompromised Host[0005]Viral infections account for substantial morbidity and mortality in the immu...

AI Technical Summary

Benefits of technology

[0017]In certain embodiments, the present invention describes the generation of multivirus CTL lines or multi-TAA CTL lines. For multivirus CTL generation, dendritic cells may be pulsed with pepmixes spanning the viral antigens or DCs may be nucleofected with plasmids encoding the viral antigens to produce antigen-presenting cells (APCs). Alternatively, PBMCs can be stimulated directly with pepmixes to activate antigen-specific cells. These strategies obviate the need to use adenovirus vectors and EBV-transformed APCs (LCLs). For multi-TAA CTL generation, DCs may be pulsed with pepmixes spanning the target antigen or DCs may be nucleofected with plasmids encoding at least part of the tumor antigens. Additional embodiments include the use of a certain cytokine(s) that act to promote proliferation and reduce cell death in the activated T-cell population, and use of cell culture in a bioreactor, such as a G-Rex bioreactor, to promote optimal T-cell expansion in vitro.

[0021]In certain embodiments related to multivirus-specific CTLs, the present invention utilizes a certain cytokine combination of IL-4 and IL-7 that acts to promote proliferation and reduce cell death in the activated T-cell population.

Problems solved by technology

Viral infections account for substantial morbidity and mortality in the immunocompromised host, for example patients who have received allogeneic stem cell transplantation (SCT).

Although pharmacological agents are standard therapy for some infections, they have substantial toxicities, generate resistant variants, and are frequently ineffective.

Despite these encouraging clinical results, the broader implementation of T-cell immunotherapy is limited by (i) the infectious virus material (EBV / CMV / Adv) generally required for CTL generation, (ii) the expense of manufacture of clinical grade vectors for antigen presentation, and (iii) the prolonged period of culture (10-12-week manufacturing process) that is required to eliminate alloreactive T cells, with its attendant demands on technical skill and time.

However, both these approaches are expensive and require a large starting blood volume, which is not always available, particularly in the matched unrelated donor setting.

Antigen-specific T cells with other functions may be lost So far, their use has been limited to restricted cases of urgent medical need.

However, >70% of the patients referred to our studies have EBV negative lymphomas and are not eligible for EBV antigen-specific T cells.

One of the challenges of adoptive immunotherapy for non-viral cancers remains the identification of strongly immunogenic target antigens.

However, the majority of antigens do not meet these criteria since they are not necessarily neo-antigens uniquely present in cancer cells but rather antigens that are also expressed in normal cells and against which peripheral blood T cells are tolerized or deleted.

However, the collection of autologous TILs is not possible for most tumors.

Furthermore the in vitro expansion of large numbers of tumor-specific T cells (>1010 CTL) is a complex and expensive procedure.

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