Local ocular anaphylaxis to papain enzyme contained in a contact lens cleansing solution

Cari p 1, a Novel Polygalacturonase Allergen From Papaya Acting as Respiratory and Food Sensitizer

Papaya has been reported to elicit IgE-mediated hypersensitivity via pollen inhalation and fruit consumption. Certain papaya sensitive patients with food allergy were found to experience recurrent respiratory distresses even after quitting the consumption of fruits. This observation prompted us to investigate the allergens commonly present in fruits and pollen grains of papaya. A discovery approach consisting of immunoproteomic detection followed by molecular characterization led to the identification of a novel papaya allergen designated as Cari p 1. This allergen was detected as a 56 kDa IgE-reactive protein from pollen as well as fruit proteome through serological analysis. The protein was identified as an endopolygalacturonase by tandem mass spectrometry. Full length Cari p 1 cDNA was isolated from papaya pollen, cloned in expression vector, and purified as recombinant allergen. The recombinant protein was monomeric and displayed pectinolytic activity. Recombinant Cari p 1 reacted with IgE-antibodies of all the papaya sensitized patient sera. In addition to IgE-reactivity, rCari p 1 displayed allergenic activity by stimulating histamine release from IgE-sensitized granulocytes. CD-spectroscopy of rCari p 1 revealed the presence of predominantly β-sheet characters. The melting curve of the allergen showed partial refolding from a fully denatured state indicating the possible presence of conformational IgE-epitopes characteristic of inhalant allergens in addition to the linear IgE-epitopes of food allergens. The expression of this allergen in papaya fruits was detected by immunoblot with anti-Cari p 1 rabbit IgG and reconfirmed by PCR. In an in vivo mouse model, rCari p 1 exhibited a comparable level of inflammatory responses in the lung and duodenum tissues explaining the dual role of Cari p 1 allergen in respiratory sensitization via pollen inhalation and sensitization of gut mucosa via fruit consumption. Purified rCari p 1 can be used a marker allergen for component-resolved molecular diagnosis. Further immunological studies on Cari p 1 are warranted to design immunotherapeutic vaccine for the clinical management of papaya allergy.

Papain Induced Occupational Asthma with Kiwi and Fig Allergy

Papain is a proteolytic enzyme which is widely used in food industry, pharmaceuticals, and cosmetics. Occupational and non-occupational papain allergies have previously been documented; however, there are limited publications about papain allergy with its relative fruit allergy. Here, we present a case of occupational, IgE-mediated papain allergy with kiwi fruit and fig fruit allergy. A 53-year-old man suffered from rhinitis for several years, with the onset of his symptoms coinciding with the time he started to work at a sausage processing plant where papain is often used as a meat tenderizer. He began to experience symptoms of chest tightness, shortness of breath and wheezing shortly after starting work 5 years ago. Furthermore, he experienced several episodes of oral itching, and tongue and oropharyngeal angioedema after injestion of kiwi fruit and fig fruit. The patient had a lifelong history of allergic conjunctivitis, allergic rhinitis, and childhood asthma. Specific IgE was positive to kiwi fruit, papain and chymopapain (2.95 kUA/L, >100 kUA/L, and 95.0 kUA/L, respectively). Similar bands at 10-15 kDa in blotting with papain and kiwi fruit extracts were found. This patient showed a potential association between papain allergy and sensitization to kiwi fruit. We also reviewed 13 patients with papain allergy published in the literature, with 85% (11/13) of the patients sensitized through the respiratory tract, and 40% (4/11) having atopy. Further studies should focus on the determination of cross-reactive allergens between papain and its fruit relatives, and the prevalence of food allergy in patients with papain allergy should be investigated in a relatively large cohort.

Papain Degrades Tight Junction Proteins of Human Keratinocytes In Vitro and Sensitizes C57BL/6 Mice via the Skin Independent of its Enzymatic Activity or TLR4 Activation

Papain is commonly used in food, pharmaceutical, textile, and cosmetic industries and is known to induce occupational allergic asthma. We have previously shown that the papain-like cysteine protease Dermatophagoides pteronyssinus 1 from house dust mite exhibits percutaneous sensitization potential. We aimed here to investigate the potential of papain itself in epicutaneous sensitization. The effects of papain on tight junction (TJ) proteins were tested in vitro in human primary keratinocytes. Using C57BL/6 wild-type and Toll-like receptor 4 (TLR4)-deficient mice, we analyzed the sensitization potential of papain, its effects on the skin barrier, and immune cell recruitment. Our results show that papain affects the skin barrier by increasing transepidermal water loss, degrading TJ proteins and inducing vasodilation. When topically applied, papain exhibited a high epicutaneous inflammatory potential by recruiting neutrophils, mast cells, and CD3-positive cells and by induction of a TH2-biased antibody response. However, its high potency for specific sensitization via the skin was TLR4 independent and, in spite of its capacity to degrade epidermal TJ proteins, does not rely on its enzymatic function. From our data, we conclude that papain has all features to act as a strong allergen via the skin.

Development of allergic antibody to an enzyme in a body lotion: results of an 18-month clinical study

Use of enzymes in cosmetic products is novel and the safety of these products is not well understood. The safety of a prototype enzyme-containing body moisturizer lotion was tested via measures of skin compatibility and potential to induce protease-specific IgE antibody in a clinical study. Female, atopic subjects (n = 1,100) used body lotion containing 100 ppm protease (Y217L BPN') for 5 consecutive days per month, for 18 months. Regular lotion was used the remaining days of each month. Skin evaluation and skin prick tests (SPT) were conducted every 3 months. Measures of skin hydration were made in a subset of subjects at 3-month intervals: skin biopsies occurred at baseline and at the first 3-month timepoint. Serum from SPT positive subjects was tested for specific IgE in an immunoCAP assay. Clinical evaluation and histopathology showed no skin irritation and increased hydration of the skin over time. Three of 864 subjects completing the study developed IgE antibody to the enzyme: 1 subject after 6 months product use and 2 subjects after 15 months product use. A fourth subject was found with IgE antibody 3 months after study termination. None had allergic symptoms associated with product use. Intermittent exposure to a low level of protease enzyme in a body lotion led to the development of specific IgE antibody in 0.46% of subjects. While this study showed favorable skin compatibility of the protease containing lotion, the occurrence of allergic antibody to the enzyme was unacceptable for product commercialization.

The role of regulatory T cells in allergy

Atopic diseases are characterized by Th2 and IgE responses to common environmental and food antigens. In vivo, IgE production depends on interactions between allergen-specific B lymphocytes and Th2 lymphocytes. IgE levels are extremely low in normal individuals, suggesting that IgE production is under strong regulation. One of the reasons behind the lack of atopy in healthy individuals is the activity of regulatory T cells, which prevent naïve T helper cell precursors from acquiring a differentiated Th2 phenotype. In addition to naturally occurring regulatory T cells, atopy can be prevented by allergen-specific tolerant/regulatory cells induced through mucosal stimulation, and by mechanisms that directly suppress Iepsilon sterile transcript production on activated B lymphocytes. This article reviews the recent progress on thymic-derived as well as peripherally induced regulatory T cells as they relate to atopy. The latter discussion also includes regulatory T cells that arise through immunotherapy.

Anaphylactoid reaction to chymopapain

Chymopapain is a proteolytic enzyme used in the chemonucleolysis of the herniated nucleus pulposus of lumbar intervertebral discs. It causes rapid hydrolysis of the noncollagenous polypeptides that maintain the tertiary structure of the chondromucoprotein of the nucleus pulposus. We report here an anaphylactoid reaction after the intervertebral injection of chymopapain.

Contact lens intolerance; allergic conjunctivitis?

20 patients complaining of contact lens intolerance were patch tested to a contact lens solution and a contact lens components battery. Contact urticaria testing was also carried out. 8 patients had positive delayed reactions on patch testing, 6 patients had positive contact urticaria reactions, and 9 patients had no reactions. These results are discussed and possible alternative diagnoses for the 9 undiagnosed patients are proposed.

Experimental sensitization to subtilisin. II. Production of specific antibodies following inhalation exposure of guinea pigs

We have previously reported the development of pulmonary sensitivity in guinea pigs exposed for 5 consecutive days to bacterial subtilisin in concentrations ranging from 1.9 to 15.0 mg proteolytic enzyme/m3. Animals exposed to lesser concentrations of 0.0083 and 0.041 mg/m3 failed to demonstrate this sensitivity. In the same study, animals exposed for 11 weeks to a subtilisin concentration of 0.00068 mg/m3 followed by 6 weeks to 0.0051 mg/m3 failed to demonstrate pulmonary sensitivity. We report here the antibody response in these animals. Both an enzyme-linked immunosorbent assay and a latex agglutination assay were developed for antibody detection. A concentration-related antibody response was detected in animals which had received acute subtilisin exposures of 0.0083 to 1.9 mg/m3. Antibody titers were not increased further upon exposure to higher subtilisin concentrations. A single 3-hr exposure to 1.9 mg/m3 resulted in the same antibody response as that produced following 5 days of exposure to the same concentration. The cumulative 17-week exposure of 1.12 mg/m3 X hr subtilisin resulted in 36% (9 of 25) of the animals producing significant levels of IgG or IgM antibodies. None of these animals demonstrated pulmonary sensitivity. These results indicate that the circulating antibody titer reflected antigen exposure levels and occurred at exposures below those necessary for production of pulmonary sensitivity.

Prospective evaluation of chymopapain sensitivity in patients undergoing chemonucleolysis

Immediate anaphylactic reactions after intradiscal chymopapain (CP) injection may occur in 1% of patients undergoing chemonucleolysis (CN). Skin prick testing to CP (10 mg/ml), a prescreening history, and CP serum-specific IgE determinations by the RAST method were performed in order to identify patients presensitized to CP before CN. Follow-up repeat CP skin testing and serum-specific IgE were done 2 to 6 weeks after CN to detect CP IgE-mediated sensitization resulting from the injection. Three of 84 patients who exhibited positive skin tests to CP before CN did not receive CP injections. Only one of the three patients (33%) was detected with elevated CP serum-specific IgE before CN. No immediate severe anaphylactic reactions caused by CP injection were encountered in the remaining 81 patients with negative CP skin tests and RASTs before CN. Eight (10%) nonlife-threatening immediate and late reactions were associated with conversion from negative skin tests and RASTs before CN to positive skin tests or RASTs after CN. Overall, 19 of 52 (37%) patients who returned for follow-up testing developed cutaneous sensitization to CP after CN. Despite the fact that RAST values after CN in these patients were significantly higher (p less than 0.002) than those with negative skin tests after CN, the sensitivity of the RAST was only 72% for identifying patients who developed positive CP skin tests after CN. This study demonstrated that CP skin testing is essential for prescreening patients because it was more sensitive than RAST for identification of CP sensitivity both before and after CN. Late allergic reactions and cutaneous sensitization to CP were common sequelae of CN.

[Allergy to chymopapain: value of predictive tests before chemonucleolysis]

It is possible to treat vertebral disc hernias by chemonucleolysis because of the enzymatic properties of chymopapain extracted from Carica papaya. But, 1% of the general population would seem to have a latent sensitivity to this protein, and would thus be at risk of presenting life-threatening anaphylactic shock. Recent clinical studies have identified different risk factors: atopy, previous food and drug allergies. A case is here reported of a 35 year old woman with a history of urticaria following anti-tetanus serum and penicillin injections, who frequently ate exotic fruit, and who was intolerant to alcohol. HBDT and prick tests confirmed both drug allergies. A prick test to chymopapain 1 mg X ml-1 gave a borderline result; the HBDT was positive, with 45% degranulation. Both these tests had been previously assessed by a study of 20 volunteers in good general health: negative prick tests in all 20, and negative HBDT in 19 out of the 20, with chymopapain concentrations ranging from 10 micrograms X ml-1 to 1 micrograms X ml-1. The one volunteer with a positive HBDT probably had latent sensitivity to the enzyme. The great sensitivity of both prick tests and HBDT in detecting IgE specific for food proteins is recalled. It is suggested that a routine predictive immuno-allergological assessment be carried out, with prick tests to the standard airbone allergens (to find a possible atopy), and a prick-test with 1 mg X ml-1 chymopapain, and a HBDT to the enzyme. A sample of serum should be kept for possible RAST and FAST carried out later.(ABSTRACT TRUNCATED AT 250 WORDS)