Olopatadine inhibits TNFalpha release from human conjunctival mast cells.

PubMed ID: 10831003

Author(s): Cook EB, Stahl JL, Barney NP, Graziano FM. Olopatadine inhibits TNFalpha release from human conjunctival mast cells. Ann Allergy Asthma Immunol. 2000 May;84(5):504-8. PMID 10831003

Journal: Annals Of Allergy, Asthma & Immunology : Official Publication Of The American College Of Allergy, Asthma, & Immunology, Volume 84, Issue 5, May 2000

BACKGROUND Tumor necrosis factor-alpha (TNFalpha) release likely plays a crucial role in allergic ocular inflammation via increasing ICAM-1 on epithelial cells and triggering other proinflammatory events. The immediate and prolonged release of TNFalpha from human conjunctival mast cells in response to allergen challenge is potentially an important target for therapeutic intervention, yet the effect of ocular anti-allergic agents on this process has not been examined. Olopatadine (Patanol) is a clinically effective dual-action ophthalmic anti-allergic agent that has been shown to inhibit mast cell histamine, tryptase, and PGD2 release in vitro and promote decreased H1 receptor binding activity in vitro and functional H1 receptor antagonism in vivo.

OBJECTIVE To investigate the effect of olopatadine on TNFalpha release from anti-IgE antibody challenged purified human conjunctival mast cells.

METHODS Human conjunctival mast cells were purified (>95%) from cadaveric tissues using a procedure combining enzymatic digestion and Percoll gradient centrifugation. These cells were incubated with olopatadine for 30 minutes then challenged with anti-IgE antibody for 90 minutes. Supernatants were analyzed for TNFalpha.

RESULTS Purified human conjunctival mast cells responded to anti-IgE antibody challenge with TNFalpha release in a concentration dependent manner (optimum concentration was 10 microg/mL). Olopatadine pre-incubation resulted in a dose-dependent decrease in anti-IgE antibody mediated TNFalpha release (IC50 = 13.1 microM). At a concentration of 3 mM olopatadine reduced TNFalpha release to the level of unchallenged controls.

CONCLUSION Olopatadine inhibited anti-IgE antibody-mediated release of TNFalpha from human conjunctival mast cells. This effect could contribute to the long duration of anti-allergic activity reported for the drug.