Innate Immune Cell Infiltration Induced by Polatuzumab Vedotin Contributes to the Antitumor Effect in Mouse Models

Area of Science:

• Immunology
• Oncology
• Pharmacology

Background:

• Diffuse large B-cell lymphoma (DLBCL) treatment outcomes are influenced by the tumor microenvironment.
• The specific role of the tumor microenvironment in Polatuzumab vedotin (Pola) efficacy is not well understood.

Purpose of the Study:

• To investigate the relationship between Pola's antitumor effect and the immune status of the tumor microenvironment.
• To identify the role of innate immune cells in mediating Pola's therapeutic activity.

Main Methods:

• Utilized a xenograft mouse model with a DLBCL cell line (DB).
• Employed a syngeneic mouse model to confirm findings.
• Conducted ex vivo co-culture experiments to assess immune cell migration and damage-associated molecular pattern release.

Main Results:

• Pola treatment induced infiltration of macrophages (MΦ) and natural killer (NK) cells in the xenograft model.
• These innate immune cells were found to contribute significantly to Pola's antitumor effect.
• Pola enhanced the release of damage-associated molecular patterns and promoted immune cell migration.

Conclusions:

• Pola treatment modulates the infiltration of MΦ and NK cells within tumors.
• Innate immune cells play an essential role in the antitumor activity of Pola.
• Understanding these interactions can inform future DLBCL treatment strategies.