Use of histamine H4 receptor antagonist for the treatment of inflammatory responses

A method of identifying compounds that modulate mammalian histamine H4 receptor protein activity, comprising:

• a) combining a putative modulator compound of mammalian histamine H4 receptor protein activity with mammalian histamine H4 receptor protein and a known histamine receptor H4 ligand;
• and
• b) measuring an effect of the modulator on the protein function or its ability to bind the ligand, wherein said effect is inhibition, activation, antagonist, agonist or reverse agonist activity,
• wherein said modulator compound is a modulator of polymorphonuclear leukocyte activation.

A method of identifying compounds that modulate mammalian histamine H4 receptor protein activity, comprising:

• a) combining a putative modulator compound of mammalian histamine H4 receptor protein activity with mammalian histamine H4 receptor protein and a known histamine receptor H4 ligand;
• and
• b) measuring an effect of the modulator on the protein function or its ability to bind the ligand, wherein said effect is inhibition, activation, antagonist, agonist or reverse agonist activity,
• wherein said modulator compound has is a modulator of mast cell activation.