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Secondary lymphoid nodule
With antigenic stimulation, primary nodules increase in size and develop a pale central region called the germinal center. They are now termed secondary nodules. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. In this early secondary nodule the germinal center is beginning to form; the increased size of the nodule ruptures through the muscularis mucosae.
![Secondary lymphoid nodule > <p>Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-3A-1-ping.png)
Secondary lymphoid nodule >
Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.
![- Germinal center <p>Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-3A-2-ping.png)
- Germinal center
Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.
![Diffuse lymphatic tissue <p>Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-3A-3-ping.png)
Diffuse lymphatic tissue
Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.
![Intestinal lumen <p>Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-3A-4-ping.png)
Intestinal lumen
Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.
![Epithelium <p>Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.</p>](https://digitalhistology.org/wp-content/uploads/2019/02/Or.Ly_.Tiss-3A-4A-ping.png)
Epithelium
Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.
![Intestinal glands <p>Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-3A-6-ping.png)
Intestinal glands
Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.
![Muscularis mucosae <p>Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-3A-7-ping.png)
Muscularis mucosae
Secondary nodules consist of an outer mantle (corona) of B lymphocytes surrounding the germinal center, where the immunoresponsive B lymphocytes are formed. The germinal center forms following antigen stimulation. The germinal center contains phagocytic cells and large, immature lymphoblasts that divide to form the smaller B lymphocytes. These B cells migrate to and accumulate at the periphery in the mantle or corona region.
![Image source > <p>Image taken of a slide from the University of Mississippi collection.</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-3A-8-ping.png)
Image source >
Image taken of a slide from the University of Mississippi collection.