This Glossary is intended to assist readers when referring to technical language used in our materials. The definitions represent the meanings understood and shared by Synairgen and the wider scientific community.

  • A

    A virus that can cause respiratory disease (e.g. the common cold), conjunctivitis and gastroenteritis

    Airways (or bronchial tubes)
    The tubes that carry air in and out of the lungs

    A substance that may provoke an allergic response in a susceptible person. Common allergens include house dust mite faeces, grass pollen and cat dander

    A protein produced by cells of the immune system which specifically recognises a target molecule known as an antigen. A key component of the body’s immune defence mechanism to foreign agents

    A molecule that is capable of stimulating production of an antibody in the body, usually a foreign and potentially toxic molecule

    Any substance that can either destroy viruses or suppress their growth

    A laboratory test used to determine parameters such as the strength of a solution, the proportion of a compound in a mixture, the potency of a drug or the purity of a preparation

    A disorder in which the airways become episodically narrowed, leading to wheeze, shortness of breath, cough and chest tightness

  • B

    Also known as beta agonists – see Bronchodilators

    Barrier Function
    Linked together by protein complexes, called tight junctions, cells lining the airways create a physical barrier to the external environment. Failure of this ‘barrier’ enables agents known to promote asthma attacks (e.g. allergens and pollutants) access to the interior tissue of the lung

    A collection of samples from clinically-characterised volunteers comprising blood, induced sputum, bronchial biopsies and epithelial cells. These samples are used to develop the complex in vitro human disease models

    A biomarker is a biochemical feature or facet that can be used to measure the progress of disease or the effects of treatment

    Medicines which relax the muscles around the airways, helping the airways to open up, so making it easier to breathe. There are several types of bronchodilators, of which short acting beta-agonist drugs are the most commonly used

  • C


    Chronic bronchitis
    An inflammation of the airways accompanied by coughing and production of phlegm. The symptoms are present for at least three months in each of two consecutive years. See COPD

    Clinical Trial Authorisation
    An authorisation from the MHRA to conduct a clinical trial

    The major structural protein of the body, forming the scaffold in between cells. Produced by fibroblast cells during wound healing to form scar tissue, it is over-produced in fibrosis.

    Chronic obstructive pulmonary disease covers two conditions: chronic bronchitis and emphysema. COPD usually results from long-term exposure to irritants to the lungs, of which the most prevalent is tobacco smoke. Unlike asthma, where airflow obstruction varies, in COPD airflow obstruction is largely irreversible

    A virus that can cause respiratory disease such as the common cold or SARS (depending on the type of coronavirus) and gastroenteritis

    In fibrosis, collagen is stiffened by the formation of chemical cross-links acting like a glue between the collagen fibres. This process is catalysed by Lysyl Oxidase (LOX) enzymes.

  • D

    Suitable for pharmaceutical development

  • E

    A destructive process involving the air spaces (alveoli) of the lungs, which leads to over-inflation of the lung and, when sufficiently advanced, causes breathlessness and lack of oxygenation of blood. See COPD

    In the lung, the epithelium is a thin layer of cells which lines the airway tubes in order to protect and regulate the tissue underneath

    A rapid deterioration of a chronic disease that makes the symptoms worse

  • F

    A type of cell that synthesises collagen. In fibrosis such as IPF, large numbers of these cells aggregate and replace the normal lung tissue.

    Stiffening of tissue, such as lung, in which healthy tissue is replaced by scar tissue consisting of large numbers of fibroblast cells and overproduction of collagen. This usually occurs in response to a repeated injury, for example liver cirrhosis may be caused by damage due to alcohol. However in IPF the cause of the injury is unknown.

  • H

    A subtype of influenza A and the most common cause of ‘flu’ in humans. The current circulating ‘swine flu’ is a H1N1 virus. The ‘H’ stands for haemagglutinin, which is a protein on the surface of influenza which allows the virus to enter the cell, thus causing infection. The ‘N’ stands for neuraminidase, a protein on the surface of influenza, which allows the newly-formed virus particles to be released from the cell

  • I

    Interferon beta is a natural protein found in the body which helps to regulate the immune system and fight off viruses. IFN-beta is currently marketed by a number of companies as an injectable therapy for the treatment of multiple sclerosis

    Interferon lambda is another natural protein found in the body which helps to regulate the immune system and fight off viruses.

    Immunoglobin E, a class of antibodies, which play a major role in allergic diseases

    In vitro
    Carried out in the laboratory, e.g. in a test tube or culture plate

    In vitro model (complex)
    A research model which contains more than one cell type and allows the study of interactions between different cell types and ‘test’ agents relevant to the disease or a therapy

    Interstitial lung disease (ILD)
    A group of lung diseases affecting the interstitium (the tissue and space around the air sacs of the lungs), of which IPF is one.

    Idiopathic: Of unknown cause Pulmonary: To do with the lungs Fibrosis: See above

  • L

    Lower airway
    The airway tubes in the lung running from the throat down, ending in the air spaces (alveoli) where gas exchange occurs

    Lysyl Oxidase, an enzyme (biological catalyst) that forms the cross-links between collagen fibres, making the collagen stiffer. It is found in most structural tissues in the body, and is important in normal production of collagen. A family of related lysyl oxidase-like enzymes (LOXL1, 2, 3 and 4) also carry out this role in different parts of the body and in response to different stimuli.

    Lysyl Oxidase-Like protein 2, a LOX-like protein that is produced in response to injury. It is found in larger amounts in lung tissue from sufferers of IPF, and is associated with worse progression of the disease. Studies inhibiting LOXL2 have shown promising results in tissue culture, pre-clinical and clinical trials.

  • M

    The mesh-like substance between cells in a tissue, which forms the structure of the tissue and on which the cells grow, like cement between bricks. Consists of different types of collagen plus a large number of other substances.

    The Medicines and Healthcare products Regulatory Agency; a UK government body tasked with ensuring that medicines and medical devices work and are safe

    Incidence or prevalence of a disease

    A gelatinous substance normally produced by the epithelium to protect and hydrate the airway surface from harmful agents

  • N

    Non-alcoholic Steatohepatitis, a disease of the liver which can lead to liver fibrosis (cirrhosis) but is not related to alcohol. It is characterised by fatty deposits and inflammation in the liver.

    An antiviral biomarker

  • P

    A virus that can cause the common cold. Parainfluenza is also responsible for 75% of croup cases in children

    Patent Cooperation Treaty or PCT
    A system by which a patent application can be filed in many different countries at once. A single international application is filed initially at a receiving office. After a search and publication, the application may be converted to a series of national applications in different countries

    Phase I Clinical Trial
    A study conducted in volunteers to determine the biological effects of a drug, especially safety and tolerability

    Phase II Clinical Trial
    A study in patients with the aim of making a preliminary determination of the efficacy of a drug to provide proof of concept and/or to study drug dose ranges

    Phase III Clinical Trial
    A full scale clinical trial to determine drug efficacy and safety prior to seeking marketing approval

    See Sputum

    Large molecules constructed of smaller biological units known as ‘amino acids’. Proteins are responsible for majority of the function and much of the structure of living things, including humans

    Relating to, functioning like, or associated with the lungs

    Pulmonary fibrosis
    Fibrosis of the lungs leading to stiffening and reduction of the usual elasticity and pliability of the lungs, making it harder to breathe and reducing the amount of oxygen that can enter the blood. It may have a range of causes, but in IPF the initial cause is not known.

  • R

    Rhinoviruses are the most common viral infective agents in humans. The most well known disease caused by rhinoviruses is the common cold

    Respiratory syncytial virus (RSV) can cause both mild respiratory illness (e.g. the common cold) and serious respiratory tract infections (such as bronchiolitis and pneumonia). More severe infections can occur in the very young, the very old and those with weakened immune systems

  • S

    Safety study
    See Phase I Clinical Trials

    Severe Acute Respiratory Syndrome (SARS) is a type of coronavirus that can cause potentially fatal respiratory illness. SARS was first reported in Asia in 2002

    The thick mucus which is coughed up by a person. Sputum contains cells and soluble substances secreted into the airways (bronchi), some of which can mediate disease if present in amounts different to normal. Sputum is also commonly called phlegm

    A group of chemicals that is produced naturally in the body by the adrenal gland. In asthma, steroids are given by inhalation or by mouth to reduce the inflammation of the airways

  • T

    Tissue engineering
    The creation of living tissues for therapeutic purposes. In Synairgen’s case, tissue is grown in complex in vitro models to recapitulate the airways

  • U

    Upper airway
    The tubes in the nose and neck which conduct air into the lung

  • V

    A virus is a non-living small particle that infects cells in biological organisms. Viruses can reproduce only by invading and controlling other cells as they lack the cellular machinery for self reproduction

  • W

    A whistling sound made by a person who has airflow obstruction when breathing