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High endothelial venules
High endothelial venules (HEVs) are modified, postcapillary venules lined by a simple cuboidal, rather than the simple squamous epithelium lining other venules. This modification allows lymphocytes to leave the blood through the HEVs and enter the lymphoid tissue. HEVs are located in the appendix, Peyer’s patch, tonsil (seen here) and lymph node. 600x
![High endothelial venules <p>High endothelial venules (HEVs) are modified, postcapillary venules lined by a simple cuboidal, rather than the simple squamous epithelium lining other venules. This modification allows lymphocytes to leave the blood through the HEVs and enter the lymphoid tissue. HEVs are located in the appendix, Peyer’s patch, tonsil (seen here) and lymph node. 600x</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-16-1-ping.png)
High endothelial venules
High endothelial venules (HEVs) are modified, postcapillary venules lined by a simple cuboidal, rather than the simple squamous epithelium lining other venules. This modification allows lymphocytes to leave the blood through the HEVs and enter the lymphoid tissue. HEVs are located in the appendix, Peyer’s patch, tonsil (seen here) and lymph node. 600x
![Venules <p>High endothelial venules (HEVs) are modified, postcapillary venules lined by a simple cuboidal, rather than the simple squamous epithelium lining other venules. This modification allows lymphocytes to leave the blood through the HEVs and enter the lymphoid tissue. HEVs are located in the appendix, Peyer’s patch, tonsil (seen here) and lymph node. 600x</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-16-2-ping.png)
Venules
High endothelial venules (HEVs) are modified, postcapillary venules lined by a simple cuboidal, rather than the simple squamous epithelium lining other venules. This modification allows lymphocytes to leave the blood through the HEVs and enter the lymphoid tissue. HEVs are located in the appendix, Peyer’s patch, tonsil (seen here) and lymph node. 600x
![Diffuse lymphoid tissue <p>High endothelial venules (HEVs) are modified, postcapillary venules lined by a simple cuboidal, rather than the simple squamous epithelium lining other venules. This modification allows lymphocytes to leave the blood through the HEVs and enter the lymphoid tissue. HEVs are located in the appendix, Peyer’s patch, tonsil (seen here) and lymph node. 600x</p>](https://digitalhistology.org/wp-content/uploads/2017/11/Or.Ly_.Tiss-16-3-ping.png)
Diffuse lymphoid tissue
High endothelial venules (HEVs) are modified, postcapillary venules lined by a simple cuboidal, rather than the simple squamous epithelium lining other venules. This modification allows lymphocytes to leave the blood through the HEVs and enter the lymphoid tissue. HEVs are located in the appendix, Peyer’s patch, tonsil (seen here) and lymph node. 600x