As the functional anatomy of the spleen is divided into red pulp, white pulp, and marginal zone, what function is incorporated into the anatomy of the cortical zone that relates to infection control?

A. Filtration of red cells, encapsulated bacteria, and other foreign material. 

DISCUSSION: The cortical networks described by Billroth are lined with B-, T-, and other lymphocyte subpopulations. The open zones, called by some the cords of Billroth, serve as an anatomic microfilter as well as a functional mechanism for removing foreign materials. For example, immature red cells with retained nuclei are “pitted” by these cords and removed from circulation. Pneumococcal and other bacteria (encapsulated and nonencapsulated) can be removed by the spleen. The filter mechanism of the spleen, combined with this immune capacity, is what is mainly lost in splenectomy that exposes the asplenic patient to overwhelming postsplenectomy sepsis syndrome (OPSS).