Children/grandchildren of an 'Agent Orange' Victim were found to have only 2% of their normal immune system. How is this tested for? One element?
Understanding the Immune System
The Anatomy of the Immune System
The organs of the immune system are stationed throughout the body. They are generally referred to as lymphoid organs because they are concerned with the growth, development, and deployment of lymphocytes, the white cells that are the key operatives of the immune system. Lymphoid organs include the bone marrow and the thymus, as well as lymph nodes, spleen, tonsils and adenoids, the appendix, and clumps of lymphoid tissue in the small intestine known as Peyer's patches. The blood and lymphatic vessels that carry lymphocytes to and from the other structures can also be considered lymphoid organs.
Cells destined to become immune cells, like all other blood cells, are produced in the bone marrow, the soft tissue in the hollow shafts of long bones. The descendants of some so-called stem cells become lymphocytes, while others develop into a second major group of immune cells typified by the large, cell-and particle-devouring white cells known as phagocytes.
The two major classes of lymphocytes are B cells and T cells. B cells complete their maturation in the bone marrow. T cells, on the other hand, migrate to the thymus, a multilobed organ that lies high behind the breastbone. There they multiply and mature into cells capable of producing immune response-that is, they become immunocompetent. In a process referred to as T cell "education," T cells in the thymus learn to distinguish self cells from nonself cells; T cells that would react against self antigens are eliminated.
Upon exiting the bone marrow and thymus, some lymphocytes congregate in immune organs or lymph nodes. Others-both B and T cells-travel widely and continuously throughout the body. They use the blood circulation as well as a bodywide network of lymphatic vessels similar to blood vessels.
Laced along the lymphatic routes-with clusters in the neck, armpits, abdomen, and groin-are small, bean-shaped lymph nodes. Each lymph node contains specialized compartments that house platoons of B lymphocytes, T lymphocytes, and other cells capable of enmeshing antigen and presenting it to T cells. Thus, the lymph node brings together the several components needed to spark an immune response.
The spleen, too, provides a meeting ground for immune defenses. A fist-sized organ at the upper left of the abdomen, the spleen contains two main types of tissue: the red pulp that disposes of worn-out blood cells and the white pulp that contains lymphoid tissue. Like the lymph nodes, the spleen's lymphoid tissue is subdivided into compartments that specialize in different kinds of immune cells. Microorganisms carried by the blood into the red pulp become trapped by the immune cells known as macrophages. (Although people can live without a spleen, persons whose spleens have been damaged by trauma or by disease such as sickle cell anemia, are highly susceptible to infection; surgical removal of the spleen is especially dangerous for young children and the immunosuppressed.)
Nonencapsulated clusters of lymphoid tissue are found in many parts of the body. They are common around the mucous membranes lining the respiratory and digestive tracts-areas that serve as gateways to the body. They include the tonsils and adenoids, the appendix, and Peyer's patches.
The lymphatic vessels carry lymph, a clear fluid that bathes the body's tissues. Lymph, along with the many cells and particles it carries-notably lymphocytes, macrophages, and foreign antigens, drains out of tissues and seeps across the thin walls of tiny lymphatic vessels. The vessels transport the mix to lymph nodes, where antigens can be filtered out and presented to immune cells.
Additional lymphocytes reach the lymph nodes (and other immune tissues) through the bloodstream. Each node is supplied by an artery and a vein; lymphocytes enter the node by traversing the walls of the very small specialized veins.
All lymphocytes exit lymph nodes in lymph via outgoing lymphatic vessels. Much as small creeks and streams empty into larger rivers, the lymphatics feed into larger and larger channels. At the base of the neck, large lymphatic vessels merge into the thoracic duct, which empties its contents into the bloodstream.
Once in the bloodstream, the lymphocytes and other assorted immune cells are transported to tissues throughout the body. They patrol everywhere for foreign antigens, then gradually drift back into the lymphatic vessels, to begin the cycle all over again.
Genes and the Markers of Self
Molecules that mark a cell as self are encoded by a group of genes that is contained in a sections of a specific chromosome known as the major histocompatibility complex (MHC). The prefix "histo" means tissue; the MHC was discovered in the course of tissue transplantation experiments. Because MHC genes and the molecules they encode vary widely in the details of their structure from one individual to another (a diversity known as polymorphism), transplants are very likely to be identified as foreign and rejected by the immune system.
Scientists eventually discovered a more natural role for the MHC: it is essential to the immune defenses. MHC markers determine which antigens an individual can respond to, and how strongly. Moreover, MHC markers allow immune cells such as B cells, T cells, and macrophages to recognize and communicate with one another.
One group of proteins encoded by the genes of the MHC are the markers of self that appear on almost all body cells. Known as class I MHC antigens, these molecules alert killer T cells to the presence of body cells that have been changed for the worse-infected with a virus or transformed by cancer-and that need to be eliminated.
A second group of MHC proteins, class II antigens, are found on B cells, macrophages, and other cells responsible for presenting foreign antigen to helper T cells. Class II products combine with particles of foreign antigen in a way that showcases the antigen and captures the attention of the helper T cell.
This focusing of T cell antigen recognition through class I and class II molecules is known as MHC (or istocompatibility) restriction.
The Cells and Secretions of the Immune System
The immune system stockpiles a tremendous arsenal of cells. Some staff the general defenses, while others are trained on highly specific targets. To work effectively, however, most immune cells require the active cooperation of their fellows. Sometimes they communicate through direct physical contact, sometimes by releasing versatile chemical messengers.
In order to have room for enough cells to match millions of possible foreign invaders, the immune system stores just a few of each specificity. When an antigen appears, those few specifically matched cells are stimulated to multiply into a full-scale army. Later, to prevent this army from overexpanding wildly, like a cancer, powerful suppressor mechanisms come into play.
Lymphocytes are small white blood cells that bear the major responsibility for carrying out the activities of the immune system; they number about one trillion. The two major classes of lymphocytes are: B cells, which grow to maturity independent of the thymus, and T cells, which are processed in the thymus. Both B cells and T cells recognize specific antigen targets.
B cells work chiefly by secreting soluble substances called antibodies into the body's fluids, or humors. (This is known as humoral immunity.) Antibodies typically interact with circulating antigens such as bacteria and toxic molecules, but are unable to penetrate living cells. T cells, in contrast, interact directly with their targets, attacking body cells that have been commandeered by viruses or warped malignancy. (This is cellular immunity.)
Although small lymphocytes look identical, even under the microscope, they can be told apart by means of distinctive molecules they carry on their cell surface. Not only do such markers distinguish between B cells and T cells, they distinguish among various subsets of cells that behave differently. Every mature T cell, for instance, carries a marker known as T3 (or CD3); in addition, most helper T cells carry a T4 (CD4) marker, a molecule that recognizes class II MHC antigens. A molecule known as T8 (CD8), which recognizes class I MHC antigens, is found on many suppressor/cytotoxic T cells. In addition, different T cells have different kinds of antigen receptors-either alpha/beta or gamma/delta.
What is MCL? Mantle Cell Lymphoma
Non-Hodgkin's lymphoma is a lethal blood-borne cancer of the immune system
a high tumor burden is greater than 500g
symptomatic: including vital organ impairment and disfigurement
said Dr. Mark S. Kaminski. "These preliminary results are encouraging and demonstrate the promise of this therapy to be more effective and less toxic than traditional chemotherapy regimens.
Non-Hodgkin's lymphoma (NHL) is a form of cancer that affects the blood and lymph tissues. According to statistics from the National Cancer Institute, approximately 270,000 people are afflicted with NHL in the United States alone. Of the total, the company estimates that approximately 140,000 people have low-grade or transformed low-grade disease. NHL currently is the sixth leading cause of death among cancers in the U.S. and has the second fastest growing mortality rate. There are approximately 54,000 new cases of NHL diagnosed each year.
In the past 14 years, physicians and molecular biologists have defined several new subtypes of Non-Hodgkins Lymphoma.
Mantle cell lymphoma is one of these and comprises 5% of all Non-Hodgkins Lymphomas diagnosed in the United States
What causes MCL?
"MCL can be defined as a population of defective lymphocytes that cannot function normally and yet are not able to die."
"None of the available conventional chemotherapy regimens appear curative; hence, consideration of innovative treatment protocols and early bone marrow or stem cell transplantation appear warranted."
Does this seem to be mostly damaged red blood cells?
What are the different types of cancer?
Taking Medications? Chart them!
July 12, 2003 posting from another's websites (2001)
Best help to know your blood health, Chart your own results
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