Timothy grass

Grass variety that is widely distributed in Northern and Central Europe. Timothy grass has a significant allergological relevance.

For Phleum pratense, 13 allergens have been identified by molecular biology:

• Phl p 1 beta-expansin (major allergen)
• Phl p 2 Grass group II/III
• Phl p 4 Berberine bridge enzymes
• Phl p 5 (protein family unknown) Major allergen, marker allergen for sensitisation to timothy grass and other grasses of the Pooideae subfamily (rye, meadow meadow grass, ryegrass)
• Phl p 6 (protein family unknown)
• Phl p 7 Polcalcin
• Phl p 11 Ole e 1-type protein family (Ole e 1-related protein)
• Phl p 12 Profilin
• Phl p 13 Polygalacturonase

The main allergens (including Phl p 1) belong to the beta-expansions, proteins that play a role in ripening processes in fruits by softening the plant cell wall. There are experimental indications that the β expansinsins could possibly be novel cysteine proteases. It is assumed that the proteolytic activity of Phl p 1, similar to that shown for Der p 1 (see below house dust mite), is important for the sensitization and manifestation of the allergy.Phl p 1 is an important cross-reactive major allergen and has a sequence identity of about 85-95% with other members of the subfamily of the Pooideae.