Complement component 1qThe complement component 1q (or simply C1q) is a protein complex involved in the complement system, which is part of the innate immune system. C1q together with C1r and C1s form the C1 complex. Antibodies of the adaptive immune system can bind antigen, forming an antigen-antibody complex. When C1q binds antigen-antibody complexes, the C1 complex becomes activated. Activation of the C1 complex initiates the classical complement pathway of the complement system.
PathogenIn biology, a pathogen (πάθος, pathos "suffering", "passion" and -γενής, -genēs "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term pathogen came into use in the 1880s. Typically, the term pathogen is used to describe an infectious microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or transmit disease.
Immune toleranceImmune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to substances or tissue that would otherwise have the capacity to elicit an immune response in a given organism. It is induced by prior exposure to that specific antigen and contrasts with conventional immune-mediated elimination of foreign antigens (see Immune response). Tolerance is classified into central tolerance or peripheral tolerance depending on where the state is originally induced—in the thymus and bone marrow (central) or in other tissues and lymph nodes (peripheral).
Antinuclear antibodyAntinuclear antibodies (ANAs, also known as antinuclear factor or ANF) are autoantibodies that bind to contents of the cell nucleus. In normal individuals, the immune system produces antibodies to foreign proteins (antigens) but not to human proteins (autoantigens). In some cases, antibodies to human antigens are produced. There are many subtypes of ANAs such as anti-Ro antibodies, anti-La antibodies, anti-Sm antibodies, anti-nRNP antibodies, anti-Scl-70 antibodies, anti-dsDNA antibodies, anti-histone antibodies, antibodies to nuclear pore complexes, anti-centromere antibodies and anti-sp100 antibodies.
Human leukocyte antigenThe human leukocyte antigen (HLA) system or complex is a complex of genes on chromosome 6 in humans which encode cell-surface proteins responsible for regulation of the immune system. The HLA system is also known as the human version of the major histocompatibility complex (MHC) found in many animals. Mutations in HLA genes may be linked to autoimmune diseases such as type I diabetes, and celiac disease. The HLA gene complex resides on a 3 Mbp stretch within chromosome 6, p-arm at 21.3.
Polyclonal B cell responsePolyclonal B cell response is a natural mode of immune response exhibited by the adaptive immune system of mammals. It ensures that a single antigen is recognized and attacked through its overlapping parts, called epitopes, by multiple clones of B cell. In the course of normal immune response, parts of pathogens (e.g. bacteria) are recognized by the immune system as foreign (non-self), and eliminated or effectively neutralized to reduce their potential damage. Such a recognizable substance is called an antigen.
Parasitic wormParasitic worms, also known as helminths, are large macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other parasitic worms such as schistosomes reside in blood vessels. Some parasitic worms, including leeches and monogeneans, are ectoparasites - thus, they are not classified as helminths, which are endoparasites. Parasitic worms live in and feed in living hosts.
Complement deficiencyComplement deficiency is an immunodeficiency of absent or suboptimal functioning of one of the complement system proteins. Because of redundancies in the immune system, many complement disorders are never diagnosed. Some studies estimate that less than 10% are identified. Hypocomplementemia may be used more generally to refer to decreased complement levels, while secondary complement disorder means decreased complement levels that are not directly due to a genetic cause but secondary to another medical condition.
Respiratory tract infectionRespiratory tract infections (RTIs) are infectious diseases involving the respiratory tract. An infection of this type usually is further classified as an upper respiratory tract infection (URI or URTI) or a lower respiratory tract infection (LRI or LRTI). Lower respiratory infections, such as pneumonia, tend to be far more severe than upper respiratory infections, such as the common cold. Upper respiratory tract infection The upper respiratory tract is considered the airway above the glottis or vocal cords; sometimes, it is taken as the tract above the cricoid cartilage.
Passive immunityPassive immunity is the transfer of active humoral immunity of ready-made antibodies. Passive immunity can occur naturally, when maternal antibodies are transferred to the fetus through the placenta, and it can also be induced artificially, when high levels of antibodies specific to a pathogen or toxin (obtained from humans, horses, or other animals) are transferred to non-immune persons through blood products that contain antibodies, such as in immunoglobulin therapy or antiserum therapy.
MicroorganismA microorganism, or microbe, is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from sixth century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation.
Bacterial vaginosisBacterial vaginosis (BV) is an infection of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urination may occur. Itching is uncommon. Occasionally, there may be no symptoms. Having BV approximately doubles the risk of infection by a number of sexually transmitted infections, including HIV/AIDS. It also increases the risk of early delivery among pregnant women.
