Talk:SH Lecture - Lymphatic Structure and Organs
SH Laboratory - Lymphatic Structure and Organs
Introduction
This practical class has 2 main parts.
The first part will look at the cellular components of blood and their development.
The second part will look at the organs and tissues associated with lymphoid (lymphatic) immune function.
The Practical involves studying selected slides from the Virtual Slide Box (some text in these practical notes modified from Virtual Slidebox Histology). Additional online self-directed learning resources are shown below. Today's Laboratory will not cover all the immune system associated with the gastrointestinal tract (GIT), just the tonsilal component.
Objectives
1. Understand the major immune cell types of blood as they appear in blood smears
2. Brief understanding of the appearance and function of blood cells
3. Understand the organization of lymphoid tissue
4. Brief understanding of the organization of thymus, spleen and tonsil
Online References
- Dee, F.R., Leaven, T. and Consoer, D. (2005) Virtual Slidebox of Histology - Hematopoietic system. Retrieved April 14, 2005, from http://www.path.uiowa.edu/cgi-bin-pub/vs/fpx_browse.cgi?cat=o_hemato&div=nlm
- UWA Blue Histology UWA Blue Histology | Blood | Lymphoid Tissues 1 | Lymphoid Tissues 2 | | appendix
UNSW Virtual Slidebox
- http://vslide1.med.unsw.edu.au/B-blood-lymphoid.html or http://web.med.unsw.edu.au/vslide/phase1/indexB3.asp
- This new link does not function http://vslide.med.unsw.edu.au/index.jsp
Blood Cell Data
Bone Marrow
Promyelocyte -> Myelocyte -> Metamyelocyte -> White Blood Cell type
Neutrophil "band form" stage before final maturation
Online Resources
UWA Blue Histology UWA Blue Histology | Blood | Lymphoid Tissues 1 | Lymphoid Tissues 2
National Institute of Allergy and Infectious Diseases National Institute of Allergy and Infectious Diseases - Immune System | Organs of the Immune System | Lymph Node | Lymphatic Vessel | Understanding the Immune System: How It Works (PDF)
JayDoc Web lymphoid
SEER Training Modules
Anatomy of the Human Body. 1918
Henry Gray (1821–1865).
THE LYMPHATIC SYSTEM consists (1) of complex capillary networks which collect the lymph in the various organs and tissues; (2) of an elaborate system of collecting vessels which conduct the lymph from the capillaries to the large veins of the neck at the junction of the internal jugular and subclavian veins, where the lymph is poured into the blood stream; and (3) lymph glands or nodes which are interspaced in the pathways of the collecting vessels filtering the lymph as it passes through them and contributing lymphocytes to it. The lymphatic capillaries and collecting vessels are lined throughout by a continuous layer of endothelial cells, forming thus a closed system. The lymphatic vessels of the small intestine receive the special designation of lacteals or chyliferous vessels; they differ in no respect from the lymphatic vessels generally excepting that during the process of digestion they contain a milk-white fluid, the chyle.
Lymphatic Vessels
The lymphatic vessels are exceedingly delicate, and their coats are so transparent that the fluid they contain is readily seen through them. They are interrupted at intervals by constrictions, which give them a knotted or beaded appearance; these constrictions correspond to the situations of valves in their interior. Lymphatic vessels have been found in nearly every texture and organ of the body which contains bloodvessels. Such non-vascular structures as cartilage, the nails, cuticle, and hair have none, but with these exceptions it is probable that eventually all parts will be found to be permeated by these vessels.
Lymph Glands
The lymph glands are small oval or bean-shaped bodies, situated in the course of lymphatic and lacteal vessels so that the lymph and chyle pass through them on their way to the blood. Each generally presents on one side a slight depression—the hilus—through which the bloodvessels enter and leave the interior. The efferent lymphatic vessel also emerges from the gland at this spot, while the afferent vessels enter the organ at different parts of the periphery. On section (Fig. 597) a lymph gland displays two different structures: an external, of lighter color—the cortical; and an internal, darker—the medullary. The cortical structure does not form a complete investment, but is deficient at the hilus, where the medullary portion reaches the surface of the gland; so that the efferent vessel is derived directly from the medullary structures, while the afferent vessels empty themselves into the cortical substance.
Lymph
Lymph, found only in the closed lymphatic vessels, is a transparent, colorless, or slightly yellow, watery fluid of specific gravity about 1.015; it closely resembles the blood plasma, but is more dilute. When it is examined under the microscope, leucocytes of the lymphocyte class are found floating in the transparent fluid; they are always increased in number after the passage of the lymph through lymphoid tissue, as in lymph glands. Lymph should be distinguished from “tissue fluid” 109 which is found outside the lymphatic vessels in the tissue spaces.
Spleen
http://www.bartleby.com/107/278.html
The splenic pulp (pulpa lienis) is a soft mass of a dark reddish-brown color, resembling grumous blood; it consists of a fine reticulum of fibers, continuous with those of the trabeculæ, to which are applied flat, branching cells. The meshes of the reticulum are filled with blood, in which, however, the white corpuscles are found to be in larger proportion than they are in ordinary blood. Large rounded cells, termed splenic cells, are also seen; these are capable of ameboid movement, and often contain pigment and red-blood corpuscles in their interior. The cells of the reticulum each possess a round or oval nucleus, and like the splenic cells, they may contain pigment granules in their cytoplasm; they do not stain deeply with carmine, and in this respect differ from the cells of the Malpighian bodies. In the young spleen, giant cells may also be found, each containing numerous nuclei or one compound nucleus. Nucleated red-blood corpuscles have also been found in the spleen of young animals.
