Immune Selective Anti-Inflammatory Derivatives (ImSAIDs) are a class of peptides that have anti-inflammatory properties. ImSAIDs work by altering the activation and migration of inflammatory cells, which are

immune In biology, immunity is the capability of multicellular organisms to resist harmful microorganisms. Immunity involves both specific and nonspecific components. The nonspecific components act as barriers or eliminators of a wide range of pathogens ...

cells responsible for amplifying the inflammatory response.

History

The ImSAIDs represent a new category of anti-inflammatory and are unrelated to steroid hormones or non steroidal anti-inflammatories. The ImSAIDs were discovered by scientists evaluating biological properties of the submandibular gland and saliva. Early work in this area demonstrated that the submandibular gland released a host of factors which regulate systemic inflammatory responses and modulate systemic immune and inflammatory reactions. Early work in identifying factors that played a role in the CST-SMG axis lead to the discovery of a seven

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha a ...

peptide Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. ...

, called the submandibular gland peptide-T. SGP-T was demonstrated to have biological activity and thermoregulatory properties related to

endotoxin Lipopolysaccharides (LPS) are large molecules consisting of a lipid and a polysaccharide that are bacterial toxins. They are composed of an O-antigen, an outer core, and an inner core all joined by a covalent bond, and are found in the outer m ...

exposure. SGP-T, an isolate of the submandibular gland, demonstrated its immunoregulatory properties and potential role in modulating the cervical sympathetic trunk-submandibular gland (CST-SMG) axis, and subsequently was shown to play an important role in the control of inflammation.

Mechanisms or ImmunoPharmacology

It is now well accepted that the immune, nervous and endocrine systems communicate and interact to control and modulate

inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

and tissue repair. One of the neuroendocrine pathways, when activated, results in the release of immune regulating peptides from the submandibular gland upon neuronal stimulation from sympathetic nerves. This pathway or communication is referred to as the cervical sympathetic trunk-submandibular gland (CST-SMG) axis, a regulatory system that plays a role in the systemic control of inflammation. Cellular Effects of feG: The cellular effects of the ImSAIDs are characterized in a number of publications. feG and related peptides are known to modulate leukocyte (white blood cells) activity by influencing cell surface receptors to inhibit excessive activation and tissue infiltration. One lead ImSAID, the tripeptide FEG (Phe-Glu-Gly) and its D-isomer feG are known to alter leukocyte adhesion involving actions on αMβ2

integrin Integrins are transmembrane receptors that facilitate cell-cell and cell-extracellular matrix (ECM) adhesion. Upon ligand binding, integrins activate signal transduction pathways that mediate cellular signals such as regulation of the cell cycle ...

, and inhibit the binding of CD16b (FCyRIII) antibody to human neutrophils. One ImSAID, termed feG, has also been shown to decrease circulating

neutrophil Neutrophils (also known as neutrocytes or heterophils) are the most abundant type of granulocytes and make up 40% to 70% of all white blood cells in humans. They form an essential part of the innate immune system, with their functions varying ...

and

eosinophil Eosinophils, sometimes called eosinophiles or, less commonly, acidophils, are a variety of white blood cells (WBCs) and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates. A ...

accumulation, decrease intracellular

oxidative Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a d ...

activity and reduced the expression of CD49d after antigen exposure,.

Lead Compound

One SGP-T derivative is a three amino acid sequence shown to be a potent

anti-inflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs remedy pain by reducing inflammation as o ...

molecule A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioche ...

with systemic effects. This three amino acid peptide is phenylalanine-

glutamine Glutamine (symbol Gln or Q) is an α-amino acid that is used in the biosynthesis of proteins. Its side chain is similar to that of glutamic acid, except the carboxylic acid group is replaced by an amide. It is classified as a charge-neutral ...

glycine Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid ( carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinog ...

(FEG) and its D- isomeric form (feG), have become the foundation for the ImSAID category.Dery RE, Mathison R, Davison J, Befus AD. "Inhibition of

allergic Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic der ...

inflammation by C-terminal peptides of the

prohormone A prohormone is a committed precursor of a hormone consisting of peptide hormones synthesized together that has a minimal hormonal effect by itself because of its expression-suppressing structure, often created by protein folding and binding additi ...

submandibular rat 1 (SMR-1). ''Int Arch Allergy Immunol.'' 2001 an-Mar;124(1-3):201-4.

References

{{DEFAULTSORT:Immune-Selective Anti-Inflammatory Derivative Anti-inflammatory agents