A descendant of the Roche Elecsys 2010, the Roche E411 Rack Edition is a well-respected benchtop immunoassay system designed and manufactured in Switzerland. The rugged and attractive analyzer holds 55 analyzes and a throughput of 86 tests per hour. Immunodiagnostic assays analyze antigen and antibody responses to infectious diseases, autoimmune diseases, immune allergies, and neoplastic diseases. An antigen is a foreign substance that enters a patient's body and causes the immune system to respond. These substances often include toxins, tumors or microorganisms such as bacteria, viruses, parasites or fungi. Antibodies are proteins produced by the body's immune system in response to an antigen. The antigen-antibody response is a natural defense against invading organisms. Most immunochemical systems employ fluorescence as their working principle. Fluorescence is the emission of electromagnetic radiation at one wavelength by a substance after absorbing energy at another wavelength. This reaction takes place in the photometer section of the analyzer. The two main methods are known as fluorescence polarization immunoassay (FFIA) and chemiluminescence immunoassay. Nephelometric and enzyme immunoassays are less commonly used methods of immunochemical analysis. Some enzymatic methods are known as: Enzyme Immunoassay (EIA), Microparticle Enzyme Immunoassay (MEIA) and Enzyme-Linked Immunosorbent Assay (ELISA). Immunodiagnostic research falls into two broad categories. Analysis for infectious disease is called serology testing, while assessment of the patient's immune system is called immunodysfunction analysis. Some immunology instruments may include comprehensive testing for routine chemistry or therapeutic drugs. Serological tests are divided into 4 main groups, as listed. The most common tests in these groups are listed below: bacterial test for syphilis, Lyme disease, Legionnaires' disease, chlamydia, strep virus test for mononucleosis, Epstein-Barr's disease, rubella, hepatitis, rabies, HIV , AIDS, Herpes fungal tests Histoplasmosis, Bacillus, Candida, Aspergillus, Cryptococcus parasite tests Toxoplasmosis, Amoebiasis Immune dysfunction tests for the diagnosis of inflammatory states, tumor states, nephrotic syndrome , liver disease, and immune dysfunction that often leads to cancer. The most common tests for dysfunction are: Quantitative Immunoglobulins (IgA, IgG, IgM) Cryoglobulin Tests Collagen, Rheumatic and Connective Tissue Disease Tests Complement Components (C3,C4,C1) Antinuclear Antibody (ANA) Antiscleroderma (SCl-70) Total Antibody Hemolytic Complement (CH50) Anti-Smooth Muscle Antibody (ASMA) Test Antimitochondrial Antibody (AMA) Test Antiparietal Cell Antibody (APCA) Test IgE Antibody Cardiolipin Antibodies Cytoplasmic Neutrophil Antibodies (ANCA) Antisperm Antibody Test Alzheimers Disease Markers.