polyclonal antibodies
Research proteins and antibodies: Polyclonal antibodies
Antibodies are proteins that circulate in the blood and the lymph. They are central constituents of the immune system. The immune system defends the body from attack by infectious agents: viruses, bacteria, parasites and fungi. It also protects against foreign, damaged, pre-cancerous and cancerous cells. The immune system must distinguish between self and non-self and inactivate, remove or destroy any non-self substances.
Immune system
The immune system is distributed throughout the body's lymphoid organs. The bone marrow and thymus are the primary lymphoid organs. The cells of the immune system are produced along with red blood cells and platelets from stem cells in the bone marrow. Immature T-cells are matured in the thymus, a gland in the chest. The secondary lymphoid organs are the spleen, appendix, tonsils, adenoids and lymph nodes. They contain reservoirs of immune cells so that any antigens in blood or lymph passing through the secondary lymphoid organs are exposed to the cells of the immune system.
Cells of the immune system. nonspecific reaction
Monocytes. Circulate in the blood and engulf and destroy antigens by phagocytosis.
Macrophages. Located in tissues, macrophages are antigen-presenting cells that engulf antigens by phagocytosis and present antigenic fragments of their proteins to B-cells and T-cells. Macrophages also clean up debris.
Dendritic cells. Found mainly in the lymphoid organs, dendritic cells are antigen-presenting cells that engulf pathogens by phagocytosis and present antigenic fragments of their proteins to B-cells and T-cells.
Neutrophils, Abundant, highly motile cells that engulf and destroy bacteria by phagocytosis.
Eosinophils, Destroy parasites by secreting enzymes to perforate them.
Basophils, Circulate in the blood and release histamine and other allergy-related substances to sustain the inflammatory response: increasing the local blood supply and causing immune cells to migrate to the site.
Mast cells, Tissue-based cells similar to basophils. Mast cells release histamine in allergic reactions.
Complement proteins, The complement system of over 35 proteins can target antigens for phagocytosis or lyse cells by perforating their cell membrane.
Cells of the immune system, specific reaction
Unactivated B-cells. B-cells carry an antibody on their cell membrane.
Plasma B-cells, When a B-cell comes in contact with its antigen it produces large quantities of identical antibodies that are released into the circulation.
Memory B-cells. Alternatively a B-cell that comes in contact with its antigen forms a long-lived memory cell that can respond in later exposures to the same antigen. Memory B-cells are the basis of immunity.
T helper cells, Activated by antigens presented by antigen-presenting cells (macrophages and dendritic cells). Activated T helper cells then produce cytokines and activate other immune cells, for example they are involved in the production of antibodies by B-cells and activation of cytotoxic T-cells. N.B. Human immunodeficiency virus (HIV) destroys T helper cells and macrophages, disabling the immune system.
Cytotoxic T-cells. All cells sample their contents and present fragments of cytosolic proteins on their cell membrane so that self-cells can be identified by the immune system. Once activated by T helper cells, cytotoxic T-cells destroy non-self foreign cells and virus-infected cells by perforating their cell membranes causing lysis and/or by inducing apoptosis. They also destroy cancerous cells and are responsible for transplant rejection.
Natural killer cells. NK cells are similar to cytotoxic T-cells in that they destroy virus-infected cells and tumour cells by perforating their cell membrane. Unlike cytotoxic T-cells, NK cells can destroy cells without activation by T helper cells.
Antibodies. Antibodies are mainly involved in the defence against bacteria and viruses. An antibody will bind to a specific region (epitope) on its antigen producing an antibody-antigen complex. The larger the antigen, the more epitopes it will have. Bound antibodies signal the cells of the immune system to destroy the antigen.
Cytokines, extracellular messenger signals released by B-cells and T-cells.
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Please note that the descriptions on this website are simplified. For more detailed information the US National Cancer Institute has an excellent presentation on the immune system and Dalhousie University's Immunology Bookcase has a comprehensive overview of immunology.
About Randox
Randox Laboratories Ltd. is a diagnostic reagent and instrument manufacturer. Randox's headquarters are in Northern Ireland with international offices and distribution agreements worldwide. Core products include:
Clinical chemistry reagents and analysers;
Biochip Array Technology reagents and analysers;
Quality control materials including
Controls, calibrators and standards,
247 Internet-driven quality control,
RIQAS external quality assessment scheme.
For more information on research proteins and polyclonal antibodies visit the Randox website at www.randox.com. Click on Products then research Proteins and Antibodies.
Monocytes. Circulate in the blood and engulf and destroy antigens by phagocytosis.
Macrophages. Located in tissues, macrophages are antigen-presenting cells that engulf antigens by phagocytosis and present antigenic fragments of their proteins to B-cells and T-cells. Macrophages also clean up debris.
Dendritic cells. Found mainly in the lymphoid organs, dendritic cells are antigen-presenting cells that engulf pathogens by phagocytosis and present antigenic fragments of their proteins to B-cells and T-cells.
Neutrophils, Abundant, highly motile cells that engulf and destroy bacteria by phagocytosis.
Eosinophils, Destroy parasites by secreting enzymes to perforate them.
Basophils, Circulate in the blood and release histamine and other allergy-related substances to sustain the inflammatory response: increasing the local blood supply and causing immune cells to migrate to the site.
Mast cells, Tissue-based cells similar to basophils. Mast cells release histamine in allergic reactions.
Complement proteins, The complement system of over 35 proteins can target antigens for phagocytosis or lyse cells by perforating their cell membrane.
Cells of the immune system, specific reaction
Unactivated B-cells. B-cells carry an antibody on their cell membrane.
Plasma B-cells, When a B-cell comes in contact with its antigen it produces large quantities of identical antibodies that are released into the circulation.
Memory B-cells. Alternatively a B-cell that comes in contact with its antigen forms a long-lived memory cell that can respond in later exposures to the same antigen. Memory B-cells are the basis of immunity.
T helper cells, Activated by antigens presented by antigen-presenting cells (macrophages and dendritic cells). Activated T helper cells then produce cytokines and activate other immune cells, for example they are involved in the production of antibodies by B-cells and activation of cytotoxic T-cells. N.B. Human immunodeficiency virus (HIV) destroys T helper cells and macrophages, disabling the immune system.
Cytotoxic T-cells. All cells sample their contents and present fragments of cytosolic proteins on their cell membrane so that self-cells can be identified by the immune system. Once activated by T helper cells, cytotoxic T-cells destroy non-self foreign cells and virus-infected cells by perforating their cell membranes causing lysis and/or by inducing apoptosis. They also destroy cancerous cells and are responsible for transplant rejection.
Natural killer cells. NK cells are similar to cytotoxic T-cells in that they destroy virus-infected cells and tumour cells by perforating their cell membrane. Unlike cytotoxic T-cells, NK cells can destroy cells without activation by T helper cells.
Antibodies. Antibodies are mainly involved in the defence against bacteria and viruses. An antibody will bind to a specific region (epitope) on its antigen producing an antibody-antigen complex. The larger the antigen, the more epitopes it will have. Bound antibodies signal the cells of the immune system to destroy the antigen.
Cytokines, extracellular messenger signals released by B-cells and T-cells.
-------------------------------------------------------------------------------------------------------
Please note that the descriptions on this website are simplified. For more detailed information the US National Cancer Institute has an excellent presentation on the immune system and Dalhousie University's Immunology Bookcase has a comprehensive overview of immunology.
About Randox
Randox Laboratories Ltd. is a diagnostic reagent and instrument manufacturer. Randox's headquarters are in Northern Ireland with international offices and distribution agreements worldwide. Core products include:
Clinical chemistry reagents and analysers;
Biochip Array Technology reagents and analysers;
Quality control materials including
Controls, calibrators and standards,
247 Internet-driven quality control,
RIQAS external quality assessment scheme.
For more information on research proteins and polyclonal antibodies visit the Randox website at www.randox.com. Click on Products then research Proteins and Antibodies.