What are lymphoid follicles?

Lymphoid follicles are small masses of tissues that contain aggregations of inflammatory cells, mainly B cells with some T cells and dendritic cells.

Are lymphoid follicles normal?

Lymphoid follicles are a normal component of gut-associated lymphatic tissue. They are aggregates of lymphocytes surrounding germinal centers that straddle the muscularis mucosae. Lymphoid follicles have an average macroscopic density of 3.8/cm of adult human colon.

Where are lymphoid follicles located?

mucosa
These lymphoid follicles are usually present within the mucosa but may occasional be present within the wall. When Rokitansky–Aschoff sinuses are present, the lymphoid follicles may surround them, forming lymph node-like structures.

What causes lymphoid aggregates in colon?

Lymphoid polyps (present in 15% of patients) are hyperplastic submucosal lymphoid aggregates, most likely due to a nonspecific infection (exposure to bacteria and viruses). Submucosal lymphoid tissue is prominent in children, particularly in the distal ileum (Peyer patches).

What is another name for lymphatic follicle?

The localized concentrations of lymphocytes that are seen in the respiratory tract, genitourinary tract, and gastrointestinal tract are lymph follicles. They are also called lymphatic nodules.

Which cells are found in lymphoid follicle?

Secondary follicles: lymphoid follicles with a germinal centre. These mostly contain B-cells. The nodes are covered by a capsule of dense connective tissue, and have capsular extensions, of connective tissue, called the trabeculae, which provide support for blood vessels entering into the nodes.

What is the purpose of ovarian follicles?

When an egg matures during a woman’s menstrual cycle, the follicle breaks open and releases the egg from the ovary for possible fertilization (the process by which an egg combines with sperm to form an embryo). Ovarian follicles may sometimes be checked to help diagnose and treat infertility.

What are reactive lymphoid follicles?

Background: Reactive lymphoid follicular hyperplasia is a benign proliferation of lymphoid follicles, which can develop wherever lymphoid tissue is present. We present the unique case of an RLFH that involved the radial nerve and presented as a peripheral nerve tumor.

What happens in lymph node follicles?

After exposure to antigen, there is a rapid proliferation of B cells. Germinal centers form in the center of B cell follicles; during this process, primary follicle cells are pushed to the periphery, where they form a mantle zone around the germinal center.

What is a prominent lymphoid follicle?

Prominent lymphoid aggregate: The term “prominent” is a descriptor often used to describe a lymphoid aggregate in GI mucosa that is larger than expected (thus possibly accounting for the endoscopic impression of a polyp).

Are lymphoid aggregates normal in colon?

Under normal conditions, the colorectal mucosa exhibits small numbers of scattered lymphocytes and plasma cells in the lamina propria and only few mucosal lymphoid aggregates (MLAs). In Crohn’s colitis, the number of lymphocytes and plasma cells in the lamina propria and of MLA is substantially increased.

Is colonic mucosa with lymphoid aggregates bad?

25 The results of this study suggest that lymphoid follicles and aggregates in colonic biopsies are evidence of gut mucosa damage and may help to predict the resolution and/or duration of diarrhea. Lymphoid follicles and aggregates have been postulated as a normal component in colonic biopsies.