Prostaglandin DP2 receptor

Last updated

PTGDR2
Identifiers
Aliases PTGDR2 , CD294, CRTH2, DL1R, DP2, GPR44, prostaglandin D2 receptor 2
External IDs OMIM: 604837; MGI: 1330275; HomoloGene: 3508; GeneCards: PTGDR2; OMA:PTGDR2 - orthologs
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_004778

NM_009962

RefSeq (protein)

NP_004769

NP_034092

Location (UCSC) Chr 11: 60.85 – 60.86 Mb Chr 19: 10.91 – 10.92 Mb
PubMed search [3] [4]
Wikidata
View/Edit Human View/Edit Mouse

Prostaglandin D2 receptor 2 (DP2 or CRTH2) is a human protein encoded by the PTGDR2 gene and GPR44. [5] DP2 has also been designated as CD294 (cluster of differentiation 294). It is a member of the class of prostaglandin receptors which bind with and respond to various prostaglandins. DP2 along with prostaglandin DP1 receptor are receptors for prostglandin D2 (PGD2). Activation of DP2 by PGD2 or other cognate receptor ligands has been associated with certain physiological and pathological responses, particularly those associated with allergy and inflammation, in animal models and certain human diseases.

Contents

Gene

The PTGDR2 gene is located on human chromosome 11 at position q12.2 (i.e. 11q12.2). It consists of two introns and three exons and codes for a G protein coupled receptor (GPCR) composed of 472 amino acids. DP2, is related to members of the chemotactic factor class of GPCRs, sharing an amino acid sequence identity of 29% with the C5a receptor, Formyl peptide receptor 1, and Formyl peptide receptor 2 receptors. DP2 has little or no such amino acid sequence relationship to the eight other Prostanoid receptors (see Eicosanoid receptor#Prostenoid receptors). [6] [7]

Expression

DP2 was found to stimulate the directed movement or chemotaxis of human T-helper type 2 cells (see T helper cell#Th1/Th2 Model for helper T cells) by binding to a receptor initially termed GPR44 and thereafter CRTH2 (for Chemoattractant Receptor-homologous molecule expressed on T-Helper type 2 cells). In addition to these T helper cells, DP2 messenger RNA is also expressed by human basophils, eosinophils, a subpopulation of cytotoxic T cells (i.e. CD8+ T cells), thalamus, ovary, and spleen, and, in the central nervous system, by the frontal cortex, pons, hippocampus, and at lower levels, hypothalamus and caudate nucleus/putamen. These transcripts are also detected in fetal liver and thymus. [8] [7] [9]

Ligands

Activating ligands

The following standard prostaglandins have the following relative affinities and potencies in binding to and activating DP2: PGD2>>PGF2alpha=PGE2>PGI2=thromboxane A2. The cyclopentenone prostaglandins, PGJ2, Δ12-PGJ2, and 15-d-Δ12,14-PGJ2 are spontaneously formed or protein-facilitated derivatives of PGD2 that are generated in vitro as well as in vivo; these derivatives have binding affinities and activating potencies on DP2 that are similar to PGD2. Studies suggest that at least some if not most or all of the cytotoxic effects of cylopenenone prostaglandin derivatives of PGD2 act independently of DP2. Certain metabolites and derivatives of PGD2 viz., 13,14-dihydro-15-keto-PGD2 and 15(S)-15-methyl-PGD2, are ~10-fold less active than PGD2 while the drug indomethacin is weak in activating DP2. [9]

Inhibiting ligands

The following compounds are selective receptor antagonists of and thereby inhibit the activation of DP2: fevipiprant, setipiprant, ADC-3680, AZD-1981, MK-1029, MK-7246, OC-459, OC000459, QAV-680, and TM30089. Ramatroban and vidupiprant are non-selective (i.e. known to influence other receptors) antagonists of DP2. [9]

Mechanisms of cell activation

G protein-coupled receptors (GPCRs) such as DP2 are integral membrane proteins that, when bound by their cognate ligands (or, in some cases, even when not ligand-bound and thereby acting continuously in a constitutive manner {see Receptor (biochemistry)#Constitutive activity}), mobilize one or more types of Heterotrimeric G proteins. DP2 is classified as a "contractile" prostanoid receptor in that it can cause the contraction of smooth muscle. As evidenced by its initial discovery as a receptor for PGD2 in T-helper type 2 cells, activated DP2 triggers Gi alpha subunit-linked heterotrimeric G proteins to dissociate into their component a) Gi alpha subunits (also termed Giα subunits) inhibit adenylyl cyclase b) G beta-gamma complex of subunits (Gβγ) have many potential functions, including simulation of phospholipase C to cleave phosphatidylinositol triphosphate into inositol triphosphate (IP3) and diacylglycerol (DAG), inhibition or stimulation of adenylyl cyclase depending on the isoform, activation of GIRK channels and activation of GRK. IP3 raises cytosolic Ca2 levels thereby regulating Ca2-sensitive signal pathways; DAG activates certain protein kinase C enzymes )PKCs) that phosphorylate and thereby regulate target proteins involved in cell signaling; and adenyl cyclase converts AMP into cyclic AMP (cAMP) thereby down-regulating cAMP-responsive proteins involved in cell signalling. [10] [11] Concurrently with the mobilization of these pathways, activated DP2 also mobilizes G protein-coupled receptor kinases (GRKs, GRK2, GRK3, and/or GRK6) and Arrestin-2 (also termed Arrestin beta 1 or β-arrestin). The GRKs, along with the DAG-activated PKCs, phosphorylate DP2 to promote its internalization while arrestin-2 inhibits DP2 from further activating heterotrimeric G proteins while also linking DP2 to elements, clathrin and clathrin adaptor AP2, of the receptor internalization machinery. These pathways render DP2 unable to mobilize heterotrimereic G proteins [12] thereby rendering the cell less sensitive or insensitive to further stimulation by DP ligands. The process, termed Homologous desensitization, serves as a physiological limiter of cell responses to DP2 activators. [12] [13] [14]

Function

Allergy

Ligands that activate DP2 stimulate the in vitro chemotaxis (i.e. directed migration) of leukocytes active in mediating allergic responses viz., eosinophils, basophils, and Th2 cells. DP2 activation also stimulates eosinophils and basophils to release the many pro-allergic elements of their granules to the extracellular milieu. [10] Ligand-induced activation of DP2 has similar activities in vivo it stimulates the accumulation on and activation of eosinophils, basophils, and Th2 cells at sites of nascent inflammation in animal models. [11] PGD2, acting through DP2, stimulates the in vitro chemotaxis of CD8+ cells, although the contribution of this to the in vivo function of DP2 has not been clarified. [15]

PDP2 receptor antagonists have been shown to allergic reactions induced in the airways mice and sheep as well as the airways and nose of guinea pigs. [15]

Mice genetically engineered to be deficient in DP2 (i.e. DP2−/-) mice are defective in mounting asthmatic responses in models of: a) allergen-induced asthma, b) dermal allergy, c) ACTH and cortisol release in response to inflammatory stimuli, and c) perception of pain caused by inflammation in peripheral tissues. [10] [11] [16] DP2−/- mice are also highly resistant to the gram (-) bacterial sepsis caused by cecal ligation and puncture; the protective effect was associated with lower bacterial load and lower production of pro-inflammatory cytokines (i.e. TNF-α, IL-6, and CCL3) and increased production of an anti-inflammatory cytokine (IL-10). [8]

Embryogenesis

Studies in Dp2 gene-deficient (i.e. Dp2−/-) mice indicate that DP2 is essential for controlling cell cycle genes in fetal testes which contribute to the arrest of mitotic process and to the differentiate of germ cells. This control involves, at least in part, the DP2-dependent activation of the male germ cell marker Nanos2 and the inhibition of meiosis through repression of Stra8. [17]

Human genomics studies

The 1544G-1651G haplotype in the 3'-Untranslated region of the DP2 gene increased the stability of the gene's mRNA; this haplotype has been associated with an increased incidence of asthma in Chinese population and African but not Japanese sampling studies. [18] [19] The rs11571288 C/G Single-nucleotide polymorphism (SNP) variant [20] of DP2 has been associated with an increase in the percentage of circulating eosinophils, an increase in the expression of DP2 by these cells, an enhanced rate of differentiation of precursor cells to Th2 cells in culture, enhanced Th2 cytokine (i.e. IL-4 and IL-13) production by these cells, and an increased incidence of asthma in a sampling of multi-ethnic Caucasian Canadians. [18] [21]

Clinical studies

Allergic Diseases

Setipiprant (ACT-129968), a selective, orally active antagonist of the DP2 receptor, proved to be well tolerated and reasonably effective in reducing allergen-induced airway responses in asthmatic patient clinical trials. [22] [23] However, the drug, while supporting the concept that DP2 contributes to asthmatic disease, did not show sufficient advantage over existing drugs and was discontinued from further development for this application (see setipiprant). [24]

Patients with the chronic spontaneous urticarial form of hives exhibit significantly lower surface membrane expression of the DP22 receptor on their blood eosinophils and basophils, a result fully consistent with this receptor being initially activated and subsequently desensitization (refer to above section on "Mechanisms of cell activation"). [25] The DP2 receptor antagonist, AZD1981, is in a phase 2 clinical trial for the treatment of chronic idiopathic urticarial. [26]

A randomized, partially-blinded, placebo-controlled, two-way crossover, proof of concept study comparing the efficacy of the DP2 receptor antagonist, QAV680, in the treatment of allergic rhinitis [27] and a study on the effectiveness of OC000459, a DP2 receptor antagonist, in reducing the exacerbation of asthma induced by experimentally-induced rhinovirus infection in subjects [28] has just been completed or is underway, respectively.

Other diseases and conditions

Baldness

Acting through DP2, PGD2 can inhibit hair growth, suggesting that this receptor is a potential target for bald treatment. [29] A potential drug for blocking the DP2 receptor and thereby ameliorating baldness is the compound setipiprant. [30] A phase 2A study is underway to evaluate the safety, tolerability, and efficacy of oral setipiprant relative to a placebo in 18- to 49-year-old males with androgenetic alopecia. [31]

See also

Related Research Articles

<span class="mw-page-title-main">Eosinophil</span> Variety of white blood cells

Eosinophils, sometimes called eosinophiles or, less commonly, acidophils, are a variety of white blood cells and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates. Along with mast cells and basophils, they also control mechanisms associated with allergy and asthma. They are granulocytes that develop during hematopoiesis in the bone marrow before migrating into blood, after which they are terminally differentiated and do not multiply.

<span class="mw-page-title-main">Leukotriene</span> Class of inflammation mediator molecules

Leukotrienes are a family of eicosanoid inflammatory mediators produced in leukocytes by the oxidation of arachidonic acid (AA) and the essential fatty acid eicosapentaenoic acid (EPA) by the enzyme arachidonate 5-lipoxygenase.

<span class="mw-page-title-main">Interleukin 4</span> Mammalian protein found in Mus musculus

The interleukin 4 is a cytokine that induces differentiation of naive helper T cells (Th0 cells) to Th2 cells. Upon activation by IL-4, Th2 cells subsequently produce additional IL-4 in a positive feedback loop. IL-4 is produced primarily by mast cells, Th2 cells, eosinophils and basophils. It is closely related and has functions similar to IL-13.

<span class="mw-page-title-main">Interleukin 13</span> Protein and coding gene in humans

Interleukin 13 (IL-13) is a protein that in humans is encoded by the IL13 gene. IL-13 was first cloned in 1993 and is located on chromosome 5q31.1 with a length of 1.4kb. It has a mass of 13 kDa and folds into 4 alpha helical bundles. The secondary structural features of IL-13 are similar to that of Interleukin 4 (IL-4); however it only has 25% sequence identity to IL-4 and is capable of IL-4 independent signaling. IL-13 is a cytokine secreted by T helper type 2 (Th2) cells, CD4 cells, natural killer T cell, mast cells, basophils, eosinophils and nuocytes. Interleukin-13 is a central regulator in IgE synthesis, goblet cell hyperplasia, mucus hypersecretion, airway hyperresponsiveness, fibrosis and chitinase up-regulation. It is a mediator of allergic inflammation and different diseases including asthma., and atopic dermatitis.

<span class="mw-page-title-main">Thromboxane receptor</span> Mammalian protein found in Homo sapiens

The thromboxane receptor (TP) also known as the prostanoid TP receptor is a protein that in humans is encoded by the TBXA2R gene, The thromboxane receptor is one among the five classes of prostanoid receptors and was the first eicosanoid receptor cloned. The TP receptor derives its name from its preferred endogenous ligand thromboxane A2.

<span class="mw-page-title-main">Allergic inflammation</span>

Allergic inflammation is an important pathophysiological feature of several disabilities or medical conditions including allergic asthma, atopic dermatitis, allergic rhinitis and several ocular allergic diseases. Allergic reactions may generally be divided into two components; the early phase reaction, and the late phase reaction. While the contribution to the development of symptoms from each of the phases varies greatly between diseases, both are usually present and provide us a framework for understanding allergic disease.

Most of the eicosanoid receptors are integral membrane protein G protein-coupled receptors (GPCRs) that bind and respond to eicosanoid signaling molecules. Eicosanoids are rapidly metabolized to inactive products and therefore are short-lived. Accordingly, the eicosanoid-receptor interaction is typically limited to a local interaction: cells, upon stimulation, metabolize arachidonic acid to an eicosanoid which then binds cognate receptors on either its parent cell or on nearby cells to trigger functional responses within a restricted tissue area, e.g. an inflammatory response to an invading pathogen. In some cases, however, the synthesized eicosanoid travels through the blood to trigger systemic or coordinated tissue responses, e.g. prostaglandin (PG) E2 released locally travels to the hypothalamus to trigger a febrile reaction. An example of a non-GPCR receptor that binds many eicosanoids is the PPAR-γ nuclear receptor.

CC chemokine receptors are integral membrane proteins that specifically bind and respond to cytokines of the CC chemokine family. They represent one subfamily of chemokine receptors, a large family of G protein-linked receptors that are known as seven transmembrane (7-TM) proteins since they span the cell membrane seven times. To date, ten true members of the CC chemokine receptor subfamily have been described. These are named CCR1 to CCR10 according to the IUIS/WHO Subcommittee on Chemokine Nomenclature.

Prostaglandin D<sub>2</sub> Chemical compound

Prostaglandin D2 (or PGD2) is a prostaglandin that binds to the receptor PTGDR (DP1), as well as CRTH2 (DP2). It is a major prostaglandin produced by mast cells – recruits Th2 cells, eosinophils, and basophils. In mammalian organs, large amounts of PGD2 are found only in the brain and in mast cells. It is critical to development of allergic diseases such as asthma. Research carried out in 1989 found PGD2 is the primary mediator of vasodilation (the "niacin flush") after ingestion of niacin (nicotinic acid).

Prostaglandin receptors or prostanoid receptors represent a sub-class of cell surface membrane receptors that are regarded as the primary receptors for one or more of the classical, naturally occurring prostanoids viz., prostaglandin D2,, PGE2, PGF2alpha, prostacyclin (PGI2), thromboxane A2 (TXA2), and PGH2. They are named based on the prostanoid to which they preferentially bind and respond, e.g. the receptor responsive to PGI2 at lower concentrations than any other prostanoid is named the Prostacyclin receptor (IP). One exception to this rule is the receptor for thromboxane A2 (TP) which binds and responds to PGH2 and TXA2 equally well.

Prostaglandin DP<sub>1</sub> receptor Protein-coding gene in the species Homo sapiens

The prostaglandin D2 receptor 1 (DP1), a G protein-coupled receptor encoded by the PTGDR1 gene (also termed PTGDR), is primarily a receptor for prostaglandin D2 (PGD2). The receptor is a member of the prostaglandin receptors belonging to the subfamily A14 of rhodopsin-like receptors. Activation of DP1 by PGD2 or other cognate receptor ligands is associated with a variety of physiological and pathological responses in animal models.

<span class="mw-page-title-main">Cysteinyl leukotriene receptor 1</span> Protein-coding gene in humans

Cysteinyl leukotriene receptor 1, also termed CYSLTR1, is a receptor for cysteinyl leukotrienes (LT). CYSLTR1, by binding these cysteinyl LTs contributes to mediating various allergic and hypersensitivity reactions in humans as well as models of the reactions in other animals.

Prostaglandin EP<sub>2</sub> receptor Protein-coding gene in the species Homo sapiens

Prostaglandin E2 receptor 2, also known as EP2, is a prostaglandin receptor for prostaglandin E2 (PGE2) encoded by the human gene PTGER2: it is one of four identified EP receptors, the others being EP1, EP3, and EP4, which bind with and mediate cellular responses to PGE2 and also, but with lesser affinity and responsiveness, certain other prostanoids (see Prostaglandin receptors). EP has been implicated in various physiological and pathological responses.

Prostaglandin EP<sub>3</sub> receptor Protein-coding gene in the species Homo sapiens

Prostaglandin EP3 receptor (EP3, 53kDa), is a prostaglandin receptor for prostaglandin E2 (PGE2) encoded by the human gene PTGER3; it is one of four identified EP receptors, the others being EP1, EP2, and EP4, all of which bind with and mediate cellular responses to PGE2 and also, but generally with lesser affinity and responsiveness, certain other prostanoids (see Prostaglandin receptors). EP has been implicated in various physiological and pathological responses.

<span class="mw-page-title-main">Prostaglandin F receptor</span> Protein-coding gene in the species Homo sapiens

Prostaglandin F receptor (FP) is a receptor belonging to the prostaglandin (PG) group of receptors. FP binds to and mediates the biological actions of prostaglandin F (PGF). It is encoded in humans by the PTGFR gene.

<span class="mw-page-title-main">Prostacyclin receptor</span> Mammalian protein found in Homo sapiens

The prostacyclin receptor, also termed the prostaglandin I2 receptor or just IP, is a receptor belonging to the prostaglandin (PG) group of receptors. IP binds to and mediates the biological actions of prostacyclin (also termed prostaglandin I2, PGI2, or when used as a drug, epoprostenol). IP is encoded in humans by the PTGIR gene. While possessing many functions as defined in animal model studies, the major clinical relevancy of IP is as a powerful vasodilator: stimulators of IP are used to treat severe and even life-threatening diseases involving pathological vasoconstriction.

<span class="mw-page-title-main">Ramatroban</span> Chemical compound

Ramatroban (INN) is a thromboxane receptor antagonist.

<span class="mw-page-title-main">Setipiprant</span> Chemical compound

Setipiprant (INN; developmental code names ACT-129968, KYTH-105) is an investigational drug developed for the treatment of asthma and scalp hair loss. It was originally developed by Actelion and acts as a selective, orally available antagonist of the prostaglandin D2 receptor 2 (DP2). The drug is being developed as a novel treatment for male pattern baldness by Allergan.

The prostaglandin D2 (PGD2) receptors are G protein-coupled receptors that bind and are activated by prostaglandin D2. Also known as PTGDR or DP receptors, they are important for various functions of the nervous system and inflammation. They include the following proteins:

<span class="mw-page-title-main">Fevipiprant</span> Chemical compound

Fevipiprant (INN; code name QAW039) is a drug of the piprant class that was being developed by Novartis. It is a selective, orally available antagonist of the prostaglandin D2 receptor 2 (DP2 or CRTh2).

References

  1. 1 2 3 GRCh38: Ensembl release 89: ENSG00000183134 Ensembl, May 2017
  2. 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000034117 Ensembl, May 2017
  3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. "Entrez Gene: GPR44 G protein-coupled receptor 44".
  6. "PTGDR2 prostaglandin D2 receptor 2". Gene Resources NCBI.
  7. 1 2 Marchese A, Sawzdargo M, Nguyen T, Cheng R, Heng HH, Nowak T, Im DS, Lynch KR, George SR, O'dowd BF (1999). "Discovery of three novel orphan G-protein-coupled receptors". Genomics. 56 (1): 12–21. doi:10.1006/geno.1998.5655. PMID   10036181.
  8. 1 2 Ishii M, Asano K, Namkoong H, Tasaka S, Mizoguchi K, Asami T, Kamata H, Kimizuka Y, Fujiwara H, Funatsu Y, Kagawa S, Miyata J, Ishii K, Nakamura M, Hirai H, Nagata K, Kunkel SL, Hasegawa N, Betsuyaku T (2012). "CRTH2 is a critical regulator of neutrophil migration and resistance to polymicrobial sepsis". Journal of Immunology. 188 (11): 5655–64. doi:10.4049/jimmunol.1102330. PMC   3498953 . PMID   22544936.
  9. 1 2 3 "DP2 receptor - Prostanoid receptors - IUPHAR/BPS Guide to PHARMACOLOGY". www.guidetopharmacology.org.
  10. 1 2 3 Oguma T, Asano K, Ishizaka A (2008). "Role of prostaglandin D(2) and its receptors in the pathophysiology of asthma". Allergology International. 57 (4): 307–12. doi: 10.2332/allergolint.08-RAI-0033 . PMID   18946232.
  11. 1 2 3 Ricciotti E, FitzGerald GA (2011). "Prostaglandins and inflammation". Arteriosclerosis, Thrombosis, and Vascular Biology. 31 (5): 986–1000. doi:10.1161/ATVBAHA.110.207449. PMC   3081099 . PMID   21508345.
  12. 1 2 Hohjoh H, Inazumi T, Tsuchiya S, Sugimoto Y (2014). "Prostanoid receptors and acute inflammation in skin". Biochimie. 107 Pt A: 78–81. doi:10.1016/j.biochi.2014.08.010. PMID   25179301.
  13. Roy SJ, Parent A, Gallant MA, de Brum-Fernandes AJ, Stanková J, Parent JL (2010). "Characterization of C-terminal tail determinants involved in CRTH2 receptor trafficking: identification of a recycling motif". European Journal of Pharmacology. 630 (1–3): 10–8. doi:10.1016/j.ejphar.2009.12.022. PMID   20035740.
  14. Korbecki J, Baranowska-Bosiacka I, Gutowska I, Chlubek D (2014). "Cyclooxygenase pathways". Acta Biochimica Polonica. 61 (4): 639–49. doi: 10.18388/abp.2014_1825 . PMID   25343148.
  15. 1 2 Claar D, Hartert TV, Peebles RS (2015). "The role of prostaglandins in allergic lung inflammation and asthma". Expert Review of Respiratory Medicine. 9 (1): 55–72. doi:10.1586/17476348.2015.992783. PMC   4380345 . PMID   25541289.
  16. Matsuoka T, Narumiya S (2008). "The roles of prostanoids in infection and sickness behaviors". Journal of Infection and Chemotherapy. 14 (4): 270–8. doi:10.1007/s10156-008-0622-3. PMID   18709530. S2CID   207058745.
  17. Rossitto M, Ujjan S, Poulat F, Boizet-Bonhoure B (2015). "Multiple roles of the prostaglandin D2 signaling pathway in reproduction". Reproduction. 149 (1): R49–58. doi: 10.1530/REP-14-0381 . PMID   25269616.
  18. 1 2 Cornejo-García JA, Perkins JR, Jurado-Escobar R, García-Martín E, Agúndez JA, Viguera E, Pérez-Sánchez N, Blanca-López N (2016). "Pharmacogenomics of Prostaglandin and Leukotriene Receptors". Frontiers in Pharmacology. 7: 316. doi: 10.3389/fphar.2016.00316 . PMC   5030812 . PMID   27708579.
  19. Maeda Y, Hizawa N, Takahashi D, Fukui Y, Konno S, Nishimura M (2007). "Genetic impact of functional single nucleotide polymorphisms in the 3'-UTR region of the chemoattractant receptor expressed on Th2 cells (CRTH2) gene on asthma and atopy in a Japanese population". International Archives of Allergy and Immunology. 142 (1): 51–8. doi:10.1159/000095998. PMID   17016057. S2CID   24547755.
  20. "No items found - Gene - NCBI". www.ncbi.nlm.nih.gov.
  21. Campos Alberto E, Maclean E, Davidson C, Palikhe NS, Storie J, Tse C, Brenner D, Mayers I, Vliagoftis H, El-Sohemy A, Cameron L (2012). "The single nucleotide polymorphism CRTh2 rs533116 is associated with allergic asthma and increased expression of CRTh2". Allergy. 67 (11): 1357–64. doi:10.1111/all.12003. PMID   22947041. S2CID   10104511.
  22. Diamant Z, Sidharta PN, Singh D, O'Connor BJ, Zuiker R, Leaker BR, Silkey M, Dingemanse J (2014). "Setipiprant, a selective CRTH2 antagonist, reduces allergen-induced airway responses in allergic asthmatics". Clinical & Experimental Allergy. 44 (8): 1044–52. doi:10.1111/cea.12357. PMID   24964348. S2CID   5222512.
  23. Sidharta PN, Diamant Z, Dingemanse J (2014). "Single- and multiple-dose tolerability and pharmacokinetics of the CRTH2 antagonist setipiprant in healthy male subjects". Fundamental & Clinical Pharmacology. 28 (6): 690–9. doi:10.1111/fcp.12079. PMID   24734908. S2CID   8226504.
  24. Norman P (2014). "Update on the status of DP2 receptor antagonists; from proof of concept through clinical failures to promising new drugs". Expert Opinion on Investigational Drugs. 23 (1): 55–66. doi:10.1517/13543784.2013.839658. PMID   24073896. S2CID   19977989.
  25. Oliver ET, Sterba PM, Devine K, Vonakis BM, Saini SS (2016). "Altered expression of chemoattractant receptor-homologous molecule expressed on T(H)2 cells on blood basophils and eosinophils in patients with chronic spontaneous urticaria". The Journal of Allergy and Clinical Immunology. 137 (1): 304–6. doi: 10.1016/j.jaci.2015.06.004 . PMID   26194547.
  26. "Efficacy and Safety of Chemoattractant Receptor-homologous Molecule Expressed on T Helper Type 2 (CRTh2) Antagonist AZD1981 in Chronic Idiopathic Urticaria (CIU) Antihistamines - Full Text View - ClinicalTrials.gov". clinicaltrials.gov. 13 June 2017.
  27. Clinical trial number NCT00784732 for "A Study to Compare the Efficacy of QAV680 Against Placebo in Treating Seasonal Allergic Rhinitis in an Environmental Exposure Chamber" at ClinicalTrials.gov
  28. Clinical trial number NCT02660489 for "Effect of OC459 on the Response to Rhinovirus Challenge in Asthma" at ClinicalTrials.gov
  29. Garza LA, Liu Y, Yang Z, Alagesan B, Lawson JA, Norberg SM, Loy DE, Zhao T, Blatt HB, Stanton DC, Carrasco L, Ahluwalia G, Fischer SM, FitzGerald GA, Cotsarelis G (March 2012). "Prostaglandin D2 inhibits hair growth and is elevated in bald scalp of men with androgenetic alopecia". Science Translational Medicine. 4 (126): 126ra34. doi:10.1126/scitranslmed.3003122. PMC   3319975 . PMID   22440736.
  30. Mathiesen JM, Christopoulos A, Ulven T, Royer JF, Campillo M, Heinemann A, Pardo L, Kostenis E (April 2006). "On the mechanism of interaction of potent surmountable and insurmountable antagonists with the prostaglandin D2 receptor CRTH2". Molecular Pharmacology. 69 (4): 1441–53. doi:10.1124/mol.105.017681. PMID   16418339. S2CID   6326585.
  31. Clinical trial number 2A Study of Setipiprant Tablets in Androgenetic Alopecia in Males NCT02781311Phase 2A Study of Setipiprant Tablets in Androgenetic Alopecia in Males at ClinicalTrials.gov

Further reading

This article incorporates text from the United States National Library of Medicine, which is in the public domain.