Regional lymph nodes surrounding an infected wound are enlarged. Histological examination shows increased number of macrophages, lymphocytes, and lymphatic follicles, as well as a large amount of plasma cells, in the cortical layer of the lymph nodes. What process in the lymph nodes is indicated by these histologic changes?

Answer options

1. Transplant rejection
2. Neoplastic aberration
3. Antigen stimulation
4. Congenital deficiency of lymphoid tissue
5. Acquired deficiency of lymphoid tissue

Explanation

Antigen stimulation: formation of specific antibody from plasma cells and specifically activated t- lymphocytes against an antigen, with help of antigen-presenting cells (macrophages and monocytes).