Exogenous Pigments-Lymph Nodes

Section from a bronchial lymph node. Its reticulum cells have taken up brownish-black particles, probably dust or carbon particles ( anthracotic lymph node), by phagocytosis. The organism takes up carbon dust with the inhalation of air. Lymph nodes owe their ability to work as filters to the phagocytotic capacity of the reticulum cells. By a similar mechanism, reticulum cells also retain endogenous materials such as lipids, bacteria, cell fragments and carcinoma cells.  Carotene is another exogenous pigment in animal cells. The yellowish-red plant pigment (carrots, tomatoes) is store d almost exclusively in adipose tissue. At the right edge of this figure is a section of adipose tissue 1.

1 Adipose cells

2 Marginal sinus

3 Lymph-node capsule

4 Lymph-node cortex

5 Medullary sinus

Stain: hematoxylin-eosin; magnification: × 40

References

Kuehnel, W.(2003). Color Atlas of Cytology, Histology, and Microscopic Anatomy. 4^th edition . Institute of Anatomy Universitätzu Luebeck Luebeck, Germany . Thieme Stuttgar t · New York .