Review of T Helper 2-Type Inflammatory Diseases Following Immune Checkpoint Inhibitor Treatment

Area of Science:

• Oncology
• Immunology
• Dermatology

Background:

• Immune checkpoints enable cancer cells to evade immune surveillance.
• Immune checkpoint inhibitors (ICIs) like nivolumab reactivate T cells against cancer but can cause immune-related adverse events (irAEs).
• irAEs are typically associated with T helper-1 (Th1) or T helper-17 (Th17) inflammation.

Purpose of the Study:

• To report a rare case of prurigo nodularis, a T helper-2 (Th2) mediated condition, following nivolumab therapy for lung adenocarcinoma.
• To discuss the unusual Th2-type inflammatory response in the context of PD-1/PD-L1 pathway inhibition.
• To review emerging Th2-type inflammatory diseases associated with ICI treatment.

Main Methods:

• Case report presentation.
• Review of literature on irAEs and immune checkpoint pathways.
• Analysis of the potential mechanisms linking PD-1 inhibition to Th2 responses.

Main Results:

• A patient developed prurigo nodularis six months after nivolumab treatment for lung adenocarcinoma.
• The observed prurigo nodularis suggests a Th2-type inflammatory reaction.
• This contrasts with the more common Th1/Th17 responses typically seen with irAEs.

Conclusions:

• Nivolumab treatment can induce rare Th2-type inflammatory conditions like prurigo nodularis.
• The PD-1-PD-L2 pathway may play a role in mediating Th2 responses, even with PD-1 blockade.
• Further research is needed to understand the spectrum of irAEs and their underlying immune mechanisms.