Allergy to proteases in medical laboratory technicians: A new occupational disease?

Safety evaluation of the food enzyme containing trypsin, chymotrypsin, α‐amylase and triacylglycerol lipase from porcine pancreas

The food enzyme complex, containing trypsin (EC 3.4.21.4), chymotrypsin (EC 3.4.21.1), α‐amylase (1,4‐α‐d‐glucan glucanohydrolase, EC 3.2.1.1) and triacylglycerol lipase (triacylglycerol acylhydrolase, EC 3.1.1.3), is obtained from porcine pancreas by American Laboratories, Inc., USA. The food enzyme is intended primarily for the hydrolysis of milk proteins to be used in foods for special medical or nutritional dietary management. ■■■■■ is extensively used in the manufacturing process, and residual amounts of the solvent remain in the food enzyme. The applicant estimates a typical range of ■■■■■ in the food enzyme to be 10,000–13,000 mg/kg. Directive 2009/32/EC sets a maximum residue level of 10 mg/kg for foods and food ingredients produced in the EU or imported into the EU. The use of ■■■■■ for the production of a food enzyme falls within the scope of Directive 2009/32/EC. Consequently, the food enzyme does not comply with the existing requirements within the EU governing residual amount of solvent.

Safety evaluation of food enzyme trypsin from porcine pancreas

The food enzyme trypsin (EC 3.4.21.4) is extracted from porcine pancreas by Novozymes A/S. The food enzyme is intended to be used for hydrolysis of whey proteins employed as ingredients in infant formulae, follow‐on formulae and in food for special medical purposes. Based on maximum use levels and the maximum permitted protein content in infant formula, dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be 32 mg TOS/kg body weight (bw) per day for infants. The Panel considered that this value covers all population groups consuming these formulae. In the toxicological evaluation, clinical studies with pancreatic enzymes were considered. Hypersensitivity to the pharmaceuticals was identified as the major side effect. However, allergic reactions to porcine pancreatic enzymes in hydrolysed foods have not been reported. The Panel considered that a risk of allergic sensitisation to this food enzyme after consumption of products prepared by hydrolysis of milk could not be excluded in infants but considered the likelihood to be low. Based on the origin of the food enzyme from edible parts of animals, the data provided by the applicant and supported by the evaluation of clinical studies based on pancreatic enzymes and the estimated dietary exposure, the Panel concluded that the trypsin from porcine pancreas does not give rise to safety concern under the intended conditions of use.

Safety evaluation of a food enzyme containing trypsin and chymotrypsin from porcine pancreas

The food enzyme is a serine protease complex containing trypsin (EC 3.4.21.4) and chymotrypsin (EC 3.4.21.1) obtained from porcine pancreas by Paninkret Chem.‐Pharm. Werk GmbH. The food enzyme is currently only used in protein processing to hydrolyse milk proteins. Milk protein hydrolysates and peptides are mainly used in formulae intended to have reduced allergenicity. Based on the recommended use level and the high consumption of formulae in very young babies, dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be 180 mg TOS/kg body weight (bw) per day for infants and toddlers. Toxicological evaluation was based on the available clinical studies with pancreatic enzymes. Hypersensitivity to the product was identified as the major side effect. However, the intact enzymes are inactivated during preparation of food products; therefore, the Panel considered that the likelihood of adverse effects of the intact enzyme to occur is low. The Panel considered that a risk of allergic sensitisation to these protein hydrolysates after consumption cannot be excluded, but the likelihood of occurrence was considered to be low. Based on the origin of the food enzyme from edible parts of animals, the data provided and the evaluation of clinical studies with pancreatic enzymes and the estimated dietary exposure, the Panel concluded that the food enzyme does not give rise to safety concerns when used in the production of infant formulae based on milk protein hydrolysates.

Safety evaluation of a food enzyme containing trypsin and chymotrypsin from porcine pancreas

The food enzyme is a serine protease complex, containing trypsin (EC 3.4.21.4) and chymotrypsin (EC 3.4.21.1), obtained from porcine pancreas by Neova Technologies Inc. The serine protease complex is intended to be used for hydrolysis of whey proteins employed as ingredients of infant formulae and follow-on formulae. Based on maximum use levels and the maximum permitted protein content in infant formulae, dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be 18 mg TOS/kg body weight (bw) per day for infants. In the toxicological evaluation, clinical studies with pharmaceutical preparations containing pancreatic enzymes were considered. Hypersensitivity to the pharmaceuticals was identified as the major side effect. However, allergic reactions to porcine pancreatic enzymes in hydrolysed foods have not been reported. The Panel considered that a risk of allergic sensitisation to this food enzyme after consumption of products prepared by hydrolysis of milk cannot be excluded in infants, but considers the likelihood to be low. Based on the origin of the food enzyme from edible parts of animals, the data provided by the applicant, supported by the evaluation of clinical studies with pharmaceutical preparations based on pancreatic enzymes, the Panel concluded that the porcine pancreatic enzymes do not give rise to safety concern under the intended conditions of use.

Safety evaluation of a food enzyme containing trypsin, chymotrypsin, elastase and carboxypeptidase from porcine pancreas

The food enzyme is a protease complex, containing trypsin (EC 3.4.21.4), chymotrypsin (EC 3.4.21.1), pancreatic elastase (EC 3.4.21.36) and carboxypeptidase B (EC 3.4.17.2), obtained from porcine pancreas by Neova Technologies Inc. The food enzyme is intended to be used for hydrolysis of whey proteins employed as ingredients of infant formulae, follow-on formulae and in food for special medical purposes (tube feeding). Based on maximum use levels and the maximum permitted protein content in infant formula, dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be 36 mg TOS/kg body weight (bw) per day for infants. The Panel estimates that this value covers all population groups. In the toxicological evaluation, clinical studies with pharmaceutical preparations containing pancreatic enzymes were considered. Hypersensitivity to the pharmaceuticals was identified as the major side effect. However, the intact enzymes are removed during preparation of food products; therefore, the Panel considers that the likelihood of adverse effects of the intact enzyme to occur is small. Low molecular weight peptides derived from the enzyme are still likely to be present in the protein hydrolysate. The Panel considered that a risk of allergic sensitisation to these peptides after consumption of products prepared by hydrolysis of milk, cannot be excluded in infants, but the likelihood to occur is considered to be low. Based on the origin of the food enzyme from edible parts of animals, the data provided by the applicant, supported by the evaluation of clinical studies with pharmaceutical preparations based on pancreatic enzymes, the Panel concluded that the porcine pancreatic enzymes do not give rise to safety concern under the intended conditions of use.

Sensitization to Empynase(pronase B) in exposed hospital personnel and identification of the Empynase allergen

BACKGROUND

Empynase is a proteolytic enzyme that is widely used as an anti-inflammatory drug in Korea. We evaluated the prevalence of sensitization to Empynase in association with respiratory allergy symptoms in exposed hospital personnel, and identified the IgE-binding components in the Empynase extract, using sera with high levels of specific IgE antibodies.

METHODS

A total of 154 hospital personnel (135 nurses and 19 pharmacists) who worked in a university hospital and 123 unexposed healthy control subjects were enrolled. A questionnaire was administered that addressed demographics, job category, history of atopic diseases, diverse symptoms including nasal and lower respiratory symptoms, and the association of symptoms with work. Skin prick tests (SPTs) to common aeroallergens and Empynase extract were performed. Empynase-specific IgE antibody was detected by ELISA, and ELISA inhibition tests were conducted. IgE-binding components were identified by SDS-PAGE and IgE immunoblotting.

RESULTS

Forty-two subjects (27.3%) complained of work-related respiratory symptoms (WRRS). Five nurses (3.7%) and one pharmacist (5.3%) had work-related asthma symptoms, and 34 nurses (25.2%) and six pharmacists (31.6%) had work-related rhinitis symptoms. The prevalence of sensitization to Empynase on SPTs was 20.1%, and tended to be higher in pharmacists (31.6%) than in nurses (18.5%). It was estimated that 3.9-8.4% of hospital personnel had WRRS attributable to Empynase. The duration of exposure was longer in positive SPT responders than in negative responders (51.9+/-27.5 vs. 39.2+/-27.3 months, respectively; P<0.05), and the prevalence of Empynase-positive SPTs was significantly higher in subjects with asthma than in those without asthma (57.1% vs. 18.4%, respectively; P<0.05). The levels of Empynase-specific IgE antibodies were significantly higher in pharmacists (76.1+/-83.4 OD units) and nurses (56.3+/-103.0 OD units) than in normal controls (39.8+/-12.7 OD units; P<0.05). Seven subjects (two pharmacists and five nurses) had high serum levels of Empynase-specific IgE antibodies; six of these subjects had WRRS. ELISA inhibition tests were performed with the sera of these six subjects, revealing significant inhibition only with the addition of Empynase. Four strongly staining protein bands (sizes: 36, 33, 16, and 10 kDa) from Empynase extract were observed to bind to the IgE antibodies of sensitized subjects. Conclusion Exposure to Empynase powder may cause rhinitis and asthma in hospital personnel, and the pathogenic mechanism appears to be IgE mediated.

Occupational asthma related to mouse allergen exposure and rhinoconjunctivitis due to collagenase inhalation in a laboratory technician

We describe the case of a 27-year-old patient working in a research laboratory, who developed occupational asthma to mouse proteins and presented symptoms of rhinoconjunctivitis caused by manipulation of collagenase. Specific inhalation challenge confirmed the diagnosis of occupational asthma to mouse proteins, whereas specific challenge with collagenase only evoked symptoms of rhinitis and conjunctivitis. SDS-PAGE and Western blot analysis for collagenase showed that the patient's IgE antibodies bound specifically to a protein with a molecular weight of 92 kDa. Hence, this was an unusual case of double sensitization. The sensitization to collagenase presented in this report may represent a new occupational disease in technicians working in medical or research laboratories.