IMMUNOLOGY

Detailed explanation-1: -Answer: c Explanation: Antigen presenting cells (APC) is of two types i.e. professional and non-professional antigen presenting cells. Professional antigen presenting cells are B-lymphocytes, dendritic cells, and macrophages while non-professional APCs are fibroblast, epithelial cells, glial cells etc.

Detailed explanation-2: -Antigen-presenting cells (APCs) in the GI tract include professional APCs such as dendritic cells (DCs), B cells, and macrophages, as well as nonprofessional APCs such as epithelial cells. DCs have the capacity to migrate to lymph nodes, where they can interact with naive T cells and induce an immune response.

Detailed explanation-3: -Dendritic cells (DCs) are critical for the activation of naïve CD4+ T cells and are considered professional antigen presenting cells (APCs), as are macrophages and B cells.