Changes

<p>Grossly the lymph nodes are round or bean shaped and have an outer cortex and an inner medulla. Microscopically the nodes have a follicles, paracortical zones and medullary cords and sinuses. At the hilum the medulla is present on the outer part of the node. Lymph nodes are located in series with [[Lymphatic Vessels - Anatomy & Physiology|lymphatic vessels]] and afferent vessels enter the node on its convex side and efferent vessels exit on its concave side.</p>

<p>Grossly the lymph nodes are round or bean shaped and have an outer cortex and an inner medulla. Microscopically the nodes have a follicles, paracortical zones and medullary cords and sinuses. At the hilum the medulla is present on the outer part of the node. Lymph nodes are located in series with [[Lymphatic Vessels - Anatomy & Physiology|lymphatic vessels]] and afferent vessels enter the node on its convex side and efferent vessels exit on its concave side.</p>

===Capsule and reticular framework===

===Capsule and reticular framework===

<p> The nodes are surrounded in a fibrous capsule that extends into the node as trabeculae, which provide an overall framework. Below the capsule is the sub-capsular sinus. The nodes parenchyma contain a fine network of reticular fibres and reticular cells. Reticular cells provide "scaffolding" for other cells as well as expressing surface complexes and substance to attract [[Lymphocytes - WikiBlood#T cells|T cells]], [[Lymphocytes - WikiBlood#B cells|B cells]] and dendritic cells.  

<p> The nodes are surrounded in a fibrous capsule that extends into the node as trabeculae, which provide an overall framework. Below the capsule is the sub-capsular sinus. The nodes parenchyma contain a fine network of reticular fibres and reticular cells. Reticular cells provide "scaffolding" for other cells as well as expressing surface complexes and substance to attract [[Lymphocytes - WikiBlood#T cells|T cells]], [[Lymphocytes - WikiBlood#B cells|B cells]] and [[T cell differentiation - WikiBlood#Dendritic Cells|dendritic cells]].  

The cortex has aggregations of [[Lymphocytes - WikiBlood#B cells|B cells]] (in the follicles) in its outer region and a paracortex consisting of a rim of [[Lymphocytes - WikiBlood#T cells|T cells]] surrounding these follicles. Dendritic cells are also found in close association with the [[Lymphocytes - WikiBlood#T cells|T cells]].  The medulla contains medullary cords of cells ([[Lymphocytes - WikiBlood#B cells|B cells]], plasma cells and some [[Macrophages - WikiBlood|macrophages]]) and between these cords is the medullary sinus lined with endothelial cells and [[Macrophages - WikiBlood|macrophages]].</p>

The cortex has aggregations of [[Lymphocytes - WikiBlood#B cells|B cells]] (in the follicles) in its outer region and a paracortex consisting of a rim of [[Lymphocytes - WikiBlood#T cells|T cells]] surrounding these follicles. [[T cell differentiation - WikiBlood#Dendritic Cells|Dendritic cells]] are also found in close association with the [[Lymphocytes - WikiBlood#T cells|T cells]].  The medulla contains medullary cords of cells ([[Lymphocytes - WikiBlood#B cells|B cells]], plasma cells and some [[Macrophages - WikiBlood|macrophages]]) and between these cords is the medullary sinus lined with endothelial cells and [[Macrophages - WikiBlood|macrophages]].</p>

 

===Sinuses===

===Sinuses===

<p>Three sinuses are present:

<p>Three sinuses are present: