IRBP (1-20) (human, rat) (trifluoroacetate salt)

Interphotoreceptor retinoid-binding protein (1-20) (IRBP_1-20) is a dodecapeptide fragment of IRBP, also known as retinoid-binding protein 3, which is involved in pigment regeneration by transporting retinol and retinal from photoreceptor cells to the retinal pigment epithelium.^1,2 IRBP_1-20 has been used to induce autoimmune uveoretinitis in C57BL/6 mice, which bear the H-2^b haplotype.² IRBP_1-20 (3 µM) increases the levels of IL-4, IL-5, and IL-6 secreted from primary mouse spleen lymphocytes. Immunization and rechallenge with IRBP_1-20 increases ear swelling, ocular blood vessel inflammation, immune cell infiltration, and photoreceptor layer damage, as well as retinal detachment, in IFN-γ-deficient mice.