k204 Maxatase

Description

Occupational

An occupational allergen, which may frequently induce hayfever, asthma and conjunctivitis in sensitised individuals.

Allergens

No allergens from this substance have yet been characterised. 

Environment

Allergen Exposure

Geographical distribution

Subtilisins are proteolytic enzymes of bacterial origin used in the manufacture of washing detergents. Maxatase is one of these enzymes; Alcalase, Esperase and Savinase are 3 others. These enzymes may also be found in various foods.

The enzymes are all produced using species of Bacillus. Maxatase and Alcalase (which have sometimes been considered virtually interchangeable) come from B. licheniformis, Esperase from an alkalophilic strain of a B. licheniformis, and Savinase from an alkalophilic strain of B. amyloliquefaciens (a mistaken attribution is often to B. subtilis). Alcalase and Maxatase are usually found in washing detergents recommended for use at 10 to 65°C and pH 7 to10.5. Savinase and Esperase may be used at up to pH 11 and 12, respectively.

Other enzymes used in washing detergents are the a-amylase enzymes, e.g., Termamyl, an enzyme also derived from B. licheniformis. This enzyme is also used in the production of glucose syrups. The a-amylase enzymes are particularly useful in dishwashing and de-starching detergents.

These enzymes are high-molecular-weight antigens and have been implicated in allergic rhinitis and asthma.

Potential Cross Reactivity

Clinical Experience

IgE-mediated reactions

Since the 1960s an increasing number of occupational allergies against natural and against modified recombinant enzymes has been reported. Subtilisins, enzymes frequently used in the manufacture of washing detergents, have been shown to cause allergic reactions, in particular airway sensitisation. Symptoms, results of skin prick tests, detection of specific IgE antibodies, and results of specific bronchoprovocation tests have confirmed an immunologic mechanism to these high-molecular-weight antigens (2-11). Those affected are mainly workers in the detergent industry rather than consumers (12-15).

Not all the enzymes are equipotent in their ability to induce allergic sensitisation. In guinea pig models, Termamyl was about 10-fold more potent than Alcalase/Maxatase, and the protease subtilisin B was shown to be less potent. Another protease, Savinase, was shown to be equivalent in potency to Alcalase/Maxatase. Prospective evaluation of skin-specific IgE tests of factory workers showed that sensitisations to Termamyl and Savinase were similar to sensitisations to Alcalase. The sensitisations to subtilisin B were weaker than those to Alcalase (16).

A close relationship has been described between bronchial hyperresponsiveness and the provocation dose of the enzyme. Researchers have reported that bronchopulmonary testing with solutions of the enzyme is highly sensitive and specific in confirming the diagnosis of occupational asthma due to these proteolytic enzymes (11).

In the majority of studies, sensitisation to Maxatase necessitated further avoidance of these enzymes. Contrary to these findings, in a study conducted over a 7-year period, only 3 respiratory adverse effects (all rhinitis) were reported, the authors stating that employees with positive skin prick tests can continue to work (16).

Specific IgE tests have been reported to be very useful in the diagnosis of sensitisation to these enzymes (12).

Other reactions

A 53-year-old woman developed respiratory symptoms while working with a cleaner containing subtilisins. Her symptoms intensified in the work environment and improved away from work. Computed tomography demonstrated alveolar and interstitial infiltrates with subsequent scarring. Pulmonary function showed a restrictive pattern with diminished diffusion capacity. Bronchoalveolar lavage showed lymphocytosis, and all cultures were negative. Precipitating antibodies to the enzyme were found in the patient's serum. These findings supported a diagnosis of extrinsic allergic alveolitis from the enzyme contained in the cleaner (17).