Silk allergy

Allergic reaction to proteins(glycoproteins) in silk products. The sensitizing silk proteins can appear both as inhaled type I instant type allergens and as type IV contact allergens (Vandevenne A et al. 2015), whereby contact allergic reactions are of less importance. For example, bronchial allergic asthma has been reported twice as a frequent reaction to wild silk bed and pillow fillings.

In the case of silk allergy, multiple sources are possible, e.g. the components of the pupation material of the silkworm (Bombyx mori), scale material of silk moths, larval excrement (Suzuki M et al. 1995) and sericin, a structure-giving glycoprotein of natural silk. Sericin is regarded as the main allergen when triggering inhalative type I allergies. Sericin also leads to type IV sensitization (Koller DY et al. 2007). There is cross-reactivity between natural silk, silkworm cocoon/larva and silkworm scales.

Silk proteins are highly potent aerogenic allergens (Häcki M et al.1992). Already in children (Wen et al.1990) they can lead to allergic rhinoconjunctivitis, bronchial asthma and hypersensitivity pneumonitis.

In countries such as China and Japan, where silk factories are operated on an industrial scale, occupational sensitisation to silk proteins is also observed (Goossens A et al. 1998).

Allergic reactions of the delayed type to surgical silk sutures with granuloma formation were observed in the past; they are rare today, since surgical sutures made of braided silk threads no longer play a role.

Note: Patients with atopic dermatitis find silk materials on their skin pleasant and hardly irritating. Especially this atopic clientele is at risk of developing "silk protein dermatitis". Often responsible for this is sericin, a natural component of the silk thread. The solution to this problem situation is sericin-free silk fabrics, which have been proven to be suitable for atopics (Koller DY et al. 2007)

Prick or scratch test with native material, RAST (Ph.: silk remnants/wild side, natural silk/raw silk)

Silk in daily use: Silk-containing materials are used as clothing, bed linen (also as filling material in pillows) or as furniture covers.

Silk proteins in cosmetic formulations:

• Serica powder: Silk powder is used as an additive in cosmetic products. Use as cosmetic ingredient
• Capryloyl silk amino acids: amino acid, silk, reaction products with octanoyl chloride. Cosmetic function: hair conditioning, surfactant, cleansing
• Hydrolyzed silk: Silk protein hydrolysates. Function: antistatic, hair conditioning, moisturizing, skin care
• MEA-hydrolyzed silk: silk protein hydrolysates, products with 2-aminoethanol. Function: skin caring, hair conditioning
• Palmitoyl silk amino acids: amino acids of silk, reaction products with hexydecanoyl chloride. Function: hair conditioning, cleansing
• Sericin: fibrous glycoprotein which is a component of silk protein obtained from the silkworm cocoons Function: moisturizing, skin care, hair conditioning, smoothing
• Serica powder: Powdered silk. Function: antistatic, skin caring, hair conditioning, smoothing
• Silk amino acids: silk protein hydrolysates. Function: moisturizing, hair conditioning, skin care
• Silk worm lipids: fats from silkworms. Function: Skin caring
• Steardimonium hydroxypropyl hydrolyzed silk: Function: antistatic

1. Goossens A et al (1998) Occupational dermatitis in a silk-screen maker. Contact dermatitis 39:40-42.
2. Häcki M et al (1992) Wild silk: a strong inhalation allergen. Dtsch Med Weekly 107:166-169.
3. Inoue A eet al. (21997) Textile dermatitis from silk. Contact Dermatitis 37:185.
4. Koller DY et al (2007) Action of a silk fabric treated with AEGIS in children with atopic dermatitis: a 3-month trial.Pediatric Allergy Immunol 18:335-338.
5. Kurosaki et al (1999): Fibroin allergy. IgE mediated hypersensitivity to silk suture materials. Nihon Ika Daigaku Zasshi 66: 41-44
6. Makatsori M et al (2014) Silk contact anaphylaxis. Contact dermatitis 71:314-315.
7. Niinimäki A et al. (1998) Contact urticaria from protein hydrolysates in hair conditioners. Allergy 53:1078-1082.
8. Vandevenne A et al. (2015) Immunological contact urticaria caused by a silk shirt in an atopic patient. Contact dermatitis 72:240-241.
9. Wen et al (1990): Silk-induced asthma in children: a report of 64 cases. Ann Allergy 65, 375-378 (1990)
10. Suzuki M et al (1995) Causative allergens of allergic rhinitis in Japan with special reference to silkworm moth allergen. Allergy 50:23-27.