Lymphatics lymphocytes

The SI Pi receptor and the gradient between lymphatic tissue (low SIP levels) and plasma (high SIP levels) are essential for lymphocyte trafficking. Deletion of S1PX, as well as pharmacological... 

Kerjaschki D, Regele HM, Moosberger I, et al. Lymphatic neoangiogenesis in human kidney transplants is associated with immunologically active lymphocytic infiltrates. J Am Soc Nephrol 2004 15 603-612. 

Burman A, Haworth O, Hardie DL, et al. A chemokine-dependent stromal induction mechanism for aberrant lymphocyte accumulation and compromised lymphatic return in rheumatoid arthritis. J Immunol 2005 174(3) 1693-1700. 

The lymphatic system of the skin extends up and into the papillary layers of the dermis. A dense, flat meshwork of lymphatic capillaries is found here [11]. Lymph passes into a deeper network at the lower boundary of the dermis. Serum, macrophages, and lymphocytes readily negotiate through the skin s lymphatic and vascular networks. 

Benjamin, S. A., Jones, R. K., Snipes, M. B. and Lustgarten, C. S. (1975c). Comparative effects of inhaled relatively insoluble forms of "Y, l44Ce, and "Sr on canine peripheral lymphocyte function, page 90 in Radiation and the Lymphatic System, USAEC Report No. CONF-740930 (National Technical Information Service, Springfield, Virginia). 

King CL, Mahanty S, Kumaraswami V, et al Cytokine control of parasite-specific anergy in human lymphatic filari-asis. Preferential induction of a regulatory T-helper type 2 lymphocyte subset. J Clin Invest 1993 92 1667-1673. 

A lymph node consists of a cortex and an inner medulla. The cortex is composed of an outer cortex, which contains B-lymphocytes, within lymphoid follicles, and paracortical areas, which contain mainly T-lymphocytes and dendritic cells. The proliferation of B-cells occurs in central areas, called germinal centres. The medulla consists of strings of macrophages and the B-cells that secrete the antibodies (i.e. the effector cells) these are the medullary cords (Figure 17.42). Lymph carries immune cells (e.g. lymphocytes, antigen-presenting cells) and pathogens from the tissues to the lymph nodes, via the afferent lymphatics. 

Lymphocytes, mentioned in the description of the lymphatic system and its role in clearing paitieulates, have been the subject of much recent inquiry because of interest in the immune system (Golub, 1981). 

Hematologic/Lymphatic Anemia hemolytic anemia thrombocytopenia thrombocytopenic purpura eosinophilia leukopenia granulocytopenia neutropenia bone marrow depression agranulocytosis reduction of hemoglobin or hematocrit prolongation of bleeding and prothrombin time decrease in WBC and lymphocyte counts increase in lymphocytes, monocytes, basophils, and platelets. Hypersensitivity Adverse reactions (estimated incidence, 1% to 10%) are more likely to occur in individuals with previously demonstrated hypersensitivity. In penicillin-sensitive individuals with a history of allergy, asthma, or hay fever, the reactions may be immediate and severe. 

The common mucosal immune system (CMIS) is now well established as a separate component of the host s immune apparatus, quite distinct from and independent of the systemic immune system described above. Moreover, if an immune response is induced at one site in the mucosal system this generally leads to responses at distal mucosal sites of the CMIS, presenting a potentially large advantage. It should be noted that there are approximately 6 x 1010 antibody producing cells in mucosal tissues and 2.5 x 1010 lymphocytes in the entire lymphatic system. 

The white blood cells or leukocytes are nearly a thousandfold less numerous than red cells. About 7 x 106 cells are present per ml of blood. There are three types of leukocytes lymphocytes (-26% of the total), monocytes (-7% of the total), and polymorphonuclear leukocytes or granulocytes (-70% of the total). Lymphocytes are about the same size as erythrocytes and are made in lymphatic tissue. Individual lymphocytes may survive for as long as ten years. They function in antibody formation and are responsible for maintenance of long-term immunity. 

C. Role of Glycosphingolipids as Cell Surface Receptors Both B- and T-lymphocytes emerge from bone marrow into the lymphatic tissues and enter the blood... 

We now turn to an anatomical description of lymph nodes. The lymph node is surrounded by a thick, fibrous capsule and is subdivided into compartments by trabeculae. Inside the capsule is the subcapsular or marginal sinus, which forms the entry point of lymphatic fluid into the node, via the afferent vessel. The lymph node cortex, which lies beneath the subcapsular sinus, is the location of the primary and secondary lymphoid follicles. The primary follicles are comprised of B-lymphocytes. An immune response stimulates B-cells to replicate and differentiate, converting the primary follicle into a secondary follicle or germinal center, surrounded by a zone of small lymphocytes. The paracortex surrounds the germinal centers and primary follicles and contains mostly T-lymphocytes. The medulla is composed of medullary cords, consisting of macrophages and plasma cells, and medullary sinuses. The medullary vessels include the arteries and veins, and the afferent and efferent lymphatic vessels, respectively, deliver the lymphatic fluid into and out of the lymph node. 

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