The role of macrophages type 2 and T-regs in immune checkpoint inhibitor related adverse events.

The role of macrophages type 2 and T-regs in immune checkpoint inhibitor related adverse events. Immunobiology. 2020 Sep;225(5):152009 Authors: Mihic-Probst D, Reinehr M, Dettwiler S, Kolm I, Britschgi C, Kudura K, Maggio EM, Lenggenhager D, Rushing EJ Abstract Immune checkpoint inhibitory (ICI) therapy represents a novel approach in a variety of cancers, with impressive survival benefit. With ICIs, however, a new spectrum of immune related adverse events (irAE) including life threatening hypohysitis has emerged. This autopsy study aimed to investigate inflammatory cells, PD-1 and PD-L1 expression in cases of patients who developed hypophysitis and involvement of other organs. We analysed 6 patients, who were treated with ICIs and developed hypophysitis. Two received an additional MAP-kinase inhibitor, MEK-inhibitor and cytotoxic chemotherapy. Besides the pituitary gland, all investigated adrenal glands (5/5) were affected; three cases had other organs involved (liver (2/6), thyroid (2/6), lung (1/6), myocardium (1/6), colon (1/6). The inflammatory cells of involved organs were further specified and PD1 and PDL-1 expression was analyzed using immunohistochemistry. We observed that patients treated with ICIs alone showed T-cell predominant lymphocytic infiltrates, whereas patients receiving additional therapies demonstrated an increase in B- and T-lymphocytes. Surprisingly, the dominant inflammatory population was not T-cell, but type...
Source: Immunobiology - Category: Allergy & Immunology Authors: Tags: Immunobiology Source Type: research