Timothy grass, belonging to the family of grasses, is an undemanding plant that grows almost everywhere except in areas of permafrost. It is cultivated as fodder for livestock in rural areas.
The proteins present in Timothy grass pollen are often the main cause (trigger) of pollen allergies, not only to other grasses of the same family (ryegrass, oats, timothy grass, meadow fescue, and rye) but also to birch, alder, olive, and weed pollens.
For individuals with multiple allergies, it is important to correctly identify the primary allergen responsible for the onset of the allergy. For example, the proteins in birch and Timothy grass can induce a strong cross-reaction in the body. Therefore, before starting treatment, it is crucial to precisely determine the main responsible protein.
For more accurate results, it is advisable to use one of the molecular diagnostic methods for allergies. One of the most common methods is ImmunoCap, which provides results indicating major and minor allergenic proteins (e.g., major and minor proteins of birch and Timothy grass). A comprehensive analysis called AllergoChip can also be performed.
Timothy grass pollen is a primary allergen that triggers allergic reactions in sensitive individuals from early June to August.
Timothy grass pollen is a complex allergen comprising approximately 28 allergenic proteins, including Phl p 1, Phl p 4, Phl p 5, Phl p 6, Phl p 7, and Phl p 12.
Let’s get to know them better.
Phl p 1 – the major protein, is the primary allergen of Timothy grass. The reaction to this protein is detected in 95% of patients with allergies to various grass pollens.
Structurally, this protein is similar to proteins in ryegrass (Poa p 1), meadow fescue (Lol p 1), rice (Ory s 1), Bermuda grass (Cyn d 1), Canary grass (Pha a 1), and corn (Zea m 1).
Be cautious if the tests show a reaction to both the major protein of Timothy grass and the major protein of cats (uteroglobin). In such cases, there is a high risk of developing asthma.
Phl p 2 – sensitivity to this protein can cause an immune response to proteins in meadow fescue (Lol p 2, Lol p 3), and hedgehogs (Dac g 3).
Phl p 5 – the major protein of Timothy grass. Phl p 5 is one of the most aggressive allergenic proteins of Timothy grass, triggering symptoms of allergic rhinitis and bronchial asthma. Structurally, this protein is similar to proteins in ryegrass (Poa p 5), velvet grass (Hol l 5), Canary grass (Pha a 5), meadow fescue (Lol p 5), and barley (Hor v 5).
Phl p 6 – this protein shares structural similarities with proteins in ryegrass (Poa p 5), meadow fescue (Lol p 5), Canary grass (Pha a 5), and velvet grass (Hol l 5).
Phl p 7 – profilin, a minor protein of Timothy grass pollen. It is involved in cross-reactions with many plants (birch, alder, olive, weed pollens, and others) but is not associated with cross-reactivity to food.
Phl p 7, a minor allergen of timothy grass pollen, shares a similar protein structure with allergenic proteins found in alder (Aln g 4), mugwort (Che a 3), birch (Bet v 4), olive (Ole e 3, Ole e 8), lilac (Syr v 3), ragweed (Amb a 9, Amb a 10), plantain (Cyn d 7), timothy grass (Phl p 7), mugwort (Art v 5), and juniper (Jun o 4).
Phl p 12, known as profilin, is a minor allergen of timothy grass pollen. Profilin proteins in timothy grass have a similar structure to profilins found in various plants, plant-derived food products, and latex.
Phl p 12 shares structural similarities with allergens from rubber tree latex (Hev b 8), peach (Pru p 4), lychee (Lit c 1), apple (Mal d 4), bell pepper (Cap a 2), pineapple (Ana c 1), date palm (Pho d 2), hazelnut (Cor a 2), pear (Pyr c 4), soybean (Gly m 3), banana (Mus a 1), rice (Ory s 12), corn (Zea m 12), tomato (Lyc e 1), plantain (Cyn d 12), peanut (Ara h 5), cherry (Pru av 1), sorrel (Sal k 4), melon (Cuc m 2), olive (Ole e 2), orange (Cit s 2), barley (Hor v 12), wheat (Tri a 12), amaranth (Ama r 2), carrot (Dau c 4), celery (Api g 4), birch (Bet v 2), mugwort (Art v 4), ragweed (Amb a 8), sunflower (Hel a 2), and mugwort (Che a 2).
Allergen-specific immunotherapy (ASIT), particularly when there is a reaction to the major proteins of timothy grass pollen (Phl p 1, Phl p 5), can be an effective treatment option.