Prostaglandin D₂-MOX ELISA Kit

Prostaglandin D₂ (PGD₂) is biosynthesized in the brain by a soluble, 26 kD glutathione-independent lipocalin-type PGD₂ synthase.¹ PGD₂ accumulates in the cerebrospinal fluid (CSF), where it induces physiologic sleep in rats and humans.² PGD₂ is also synthesized by mast cells and leukocytes by a cellular, myeloid-type, glutathione-dependent PGD synthase. This PGD₂ which is formed in the intracellular and vascular compartments is rapidly metabolized to 11β-PGF_2α.³ Thus, urinary measurements of PGD synthesis are most appropriately focused on the measurement of 11β-PGF_2α. Measurement of the parent eicosanoid PGD₂ is appropriate in the supernatants of cell cultures, where PGD₂ levels may reach several ng/ml, and in CSF, where concentrations of several hundred pg/ml have been measured.⁴ All studies of PGD₂ biosynthesis should take into consideration the chemical instability of PGD₂ and its rapid degradation in the presence of serum proteins such as albumin.⁵ PGD₂ also readily degrades in both acidic and basic media to give a variety of decomposition products. Similarly, antigenic protein conjugates of PGD₂, synthesized for the production of antisera, show considerable amounts of decomposition. Thus, the resulting antibody response is heterogeneous with poor specificity. This makes PGD₂ assay systems based on the parent compound unreliable and difficult to interpret. This PGD₂-MOX ELISA is based on the conversion of PGD₂ to a stable MOX derivative. Treatment of the sample with methoxylamine hydrochloride (MOX HCl) converts PGD₂ into PGD₂-MOX, preventing its further chemical degradation. The antiserum used in the assay was developed using conjugates of this derivative and is very specific for PGD₂-MOX. The assay has been validated against stable isotope dilution GC/MS. Measurements using both techniques on identical samples showed a correlation coefficient of 0.97.

Needed but not supplied: Please download the kit booklet to verify if UltraPure Water (Milli-Q or equivalent) or any other components are needed for this assay.

WARNING This product is not for human or veterinary use.

1. Urade, Y., Tanaka, T., Eguchi, N., et al. Structural and functional significance of cysteine residues of glutathione-independent prostaglandin D synthase. The Journal of Biological Chemisty 270(3), 1422-1428 (1995).

2. Satoh, S., Matsumura, H., Nakajima, T., et al. Promotion of sleep by prostaglandin D₂ in rats made insomniac by pretreatment with para-chlorophenylalanine. Neurosci. Res. 21(1), 41-50 (1995).

3. Roberts, L.J., II, and Sweetman, B.J. Metabolic fate of endogenously synthesized prostaglandin D₂ in a human female with mastocytosis. Prostaglandins 30(3), 383-400 (1985).

4. Ujihara, M., Urade, Y., Eguchi, N., et al. Prostaglandin D₂ formation and characterization of its synthetases in various tissues of adult rats. Arch. Biochem. Biophys. 260(2), 521-531 (1988).

5. Fitzpatrick, F.A., and Wynalda, M.A. Albumin-catalyzed metabolism of prostaglandin D₂. Identification of products formed in vitro. The Journal of Biological Chemisty 258(19), 11713-11718 (1983).

Johnsson, A.K., Choi, J.H., Rönnberg, E., et al. Selective inhibition of prostaglandin D₂ biosynthesis in human mast cells to overcome need for multiple receptor antagonists: Biochemical consequences. Clin. Exp. Allergy 51(4), 594-603 (2021).

Maric, J., Ravindran, A., Mazzurana, L., et al. Cytokine-induced endogenous production of prostaglandin D₂ is essential for human group 2 innate lymphoid cell activation. J. Allergy Clin. Immunol. 143(6), 2202-2214 (2019).

Fujimori, K., Aritake, K., Oishi, Y., et al. L-PGDS-produced PGD₂ in premature, but not in mature, adipocytes increases obesity and insulin resistance. Sci. Rep. 9(1), 1931 (2019).

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