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Contrived Tears with Tryptase

Contrived Tears with Tryptase (Artificial Tears) for your every need.

Our Contrived Tears with Tryptase have been developed from >15 components known to be present in tears, balancing protein, salt and pH alike, in line with accepted tear formulations and tear tryptase levels. [1-5] Our Contrived Tears with Tryptase are a low cost solution to your diagnostic testing, instrument calibration and research needs and are sold in 5, 10 and 20 ml volumes. The tear osmolarity of our normal healthy subject tears is 300 mOsms/L with a pH of 7.4 and a tryptase concentration of 2 ng/ml.

Our Contrived Tears with Tryptase Kit (artificial tears), features six 1 ml vials with differing tryptase levels. Our Contrived Tears with Tryptase have been developed from >15 components known to be present in tears, balancing protein, salt and pH alike, in line with accepted tear formulations and tryptase levels reported in the peer reviewed literature. [1-5] Our Contrived Tears with Tryptase Kit offers the same tear formulation as our Standard Tears (osmolarity - 300 mOsms/L), but with varying tryptase levels, reflecting both normal subject, 2 ng/ml tryptase, as well as higher levels of tryptase known to be present, 5, 10, 15, 20 and 25 ng/ml during allergic conjunctivitis. [1-5] Our Contrived Tears with Tryptase are a low cost solution to your diagnostic and research needs and are sold in 1 ml pre-made volumes of 2, 5, 10, 15, 20 and 25 ng/ml tryptase, with a tear osmolarity of 300 mOsms/L salt / protein, at pH 7.4.

Larger tear volumes are available on special request to This email address is being protected from spambots. You need JavaScript enabled to view it. .

All Ursa BioScience™ tear products are intended for research use only and are not intended for human or animal use

Tryptase in Tears

Tryptase is a trypsin-like neutral endoprotease that is released by human mast cell degranulation at inflammatory sites. Tryptase levels in various body fluids have been used as an indicator of mast cell activation with serum levels typically less than 11.5 ng/ml. An increased number of mast cells and elevated tryptase concentrations are known to exist in tears of patients with allergic conjunctivitis, including atopic keratoconjunctivitis (AKC) and vernal keratoconjunctivitis (VKC), with tryptase concentrations around ≈ 15±2 ng/ml [2, 4, 5], as compared to healthy patients / controls [2, 4, 5], ≈4 ± 3 ng/ml of tears.

Vernal keratoconjunctivitis (VKC) is an allergic chronic inflammatory disease, often characterized by recurrent symptoms of severe itching, photophobia, pain, lacrimation, and discharge. [6] It is more common in young males with an increased incidence between 11-13 years of age, VKC often being rarely observed in adults. Diagnosis is often based on typical signs and symptoms. Large papillae in the upper tarsal conjunctiva and corneoscleral junction are hallmark of VKC. Conjunctival biopsy reveals an increase in basophils, eosinophils, mast cells, plasma cells and lymphocytes that also appear in the smears. The tears show very high levels of histamine, tryptase, eotaxin and eosinophil cationic protein and increased adhesion molecules (VCAM-1) and leukotrienes (LTB4, LTC4). [7]

Atopic keratoconjunctivitis (AKC) is a chronic inflammatory disease affecting the eyelids and ocular surface, typically affecting young males with atopic disease. [7]

Mast Cells

Mast cells are allergic cells present in the mucous membranes of the eyes, nose, lungs and even in the skin. In an allergic response, an allergen stimulates the release of IgE antibodies, which bind to mast cells, in turn releasing compounds such as histamine and tryptase.

Allergic Conjunctivitis

Ocular Allergy (Allergic Conjunctivitis) is one of the most common ocular conditions encountered, estimated to affect 5-22 % of the population, depending on geography and age of the patients. [7] Seasonal Allergic conjunctivitis (SAC) and perineal allergic conjunctivitis (PAC) are the most commonly seen allergic conjunctivitis. Atopic keratoconjunctivitis (AKC), vernal keratoconjunctivitis (VKC), giant papillary conjunctivitis (GPC) and contact dermatitis conjunctivitis (CDC), are the remaining components of the disorder. GPC is typically caused by Micro trauma, sometimes seen with long use soft contact lenses, with CDC belonging to a non IgE mediated category of allergic reactions. [7]

Cited References

1. Bonini, S., et al., Vernal keratoconjunctivitis - a model of 5Q cytokine gene-cluster disease. International Archives of Allergy and Immunology, 1995. 107(1-3): p. 95-98.

2. Butrus, S.I., et al., The level of tryptase in human tears - an indicator of activation of conjunctival mast-cells. Ophthalmology, 1990. 97(12): p. 1678-1683.

3. Ebihara, N., et al., Tear chymase in vernal keratoconjunctivitis. Current Eye Research, 2004. 28(6): p. 417-420.

4. Magrini, L., et al., Tear tryptase levels and allergic conjunctivitis. Allergy, 1996. 51(8): p. 577-581.

5. Tabbara, K.F., Tear tryptase in vernal keratoconjunctivitis. Archives of Ophthalmology, 2001. 119(3): p. 338-342.

6. Buckley, R.J., Vernal keratoconjunctivitis. International Ophthalmology Clinics, 1988. 28(4): p. 303-308.

7. Chaudhary, B., Allergic Conjunctivitis– A Review. DOS Times, 2013. 19(4): p. 41-47



Tear Analytical  Services, such as Viscosity and  Osmolarity determination for your samples.

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