Granulomatous inflammation is typically characterized by a collection of which type of cell with a squamous-cell like appearance?

Granulomatous inflammation is primarily characterized by the accumulation of macrophages that differentiate into epithelioid cells, which exhibit a squamous-cell like appearance. This transformation occurs in response to persistent stimuli, such as infectious agents or foreign bodies, that are challenging to eliminate. The activated macrophages resemble epithelial cells because they become larger, develop abundant cytoplasm, and often form aggregates, which are typical of granulomas.

Epithelioid macrophages play a critical role in the immune response, contributing to the formation of granulomas alongside multinucleated giant cells, which are formed from the fusion of several macrophages. The presence of these cells indicates a chronic inflammatory process, often seen in conditions like tuberculosis, sarcoidosis, and certain autoimmune diseases. The distinctive appearance of granulomas, marked by these modified macrophages, is a key diagnostic feature in many systemic diseases.

Other cell types present in the immune response, such as neutrophils, B cells, and mast cells, have different roles and characteristics that do not align with the hallmark features of granulomatous inflammation. Therefore, the correct identification of macrophages as the cells that create the typical squamous-like appearance in granulomatous inflammation is crucial for understanding and diagnosing various systemic diseases