B7-H3 as a promising target for cytotoxicity T cell in human cancer therapy

Area of Science:

• Immunology
• Oncology
• Biotechnology

Background:

• B7 homolog 3 (B7-H3) is overexpressed in various human tumors.
• Targeting B7-H3 with monoclonal antibodies can inhibit tumor growth.
• The potential of B7-H3 as a target for T-cell mediated immunotherapy requires further investigation.

Purpose of the Study:

• To evaluate the expression of B7-H3 in human tumor cells.
• To assess the efficacy of activated T cells (ATCs) armed with a novel anti-CD3 x anti-B7-H3 bispecific antibody (B7-H3Bi-Ab) against tumors.
• To determine if B7-H3 can be a target for T-cell mediated immunotherapy.

Main Methods:

• Demonstrated B7-H3 expression in human tumor cells.
• Evaluated the in vitro and in vivo cytotoxic activity of B7-H3Bi-armed ATCs against tumor cells.
• Assessed cytokine secretion (IFN-γ, TNF-α, IL-2) by armed ATCs.
• Utilized severe combined immunodeficiency (SCID) xenograft models to test in vivo efficacy.

Main Results:

• B7-H3Bi-armed ATCs exhibited significantly increased cytotoxic activity against tumor cells compared to unarmed ATCs at various effector/target ratios.
• Armed ATCs secreted higher levels of IFN-γ, TNF-α, and IL-2.
• Infusion of B7-H3Bi-armed ATCs inhibited tumor growth and improved survival in SCID xenograft models.

Conclusions:

• B7-H3 is a viable target for T-cell mediated cancer immunotherapy.
• Novel B7-H3Bi-armed ATCs demonstrate potent anti-tumor activity both in vitro and in vivo.
• This therapeutic strategy holds promise for advancing cancer immunotherapy.