title: Male-specific submaxillary gland protein, a lipocalin allergen of the golden hamster, differs from the lipocalin allergens of Siberian and Roborovski dwarf hamsters.
abstract: BACKGROUND
  An increasing number of asthma cases upon exposure to hamsters and anaphylactic reactions following hamster bites are being reported, but the allergens responsible are still poorly characterized. In the Golden hamster, male-specific submaxillary gland protein (MSP), a lipocalin expressed in a sex- and tissue-specific manner in the submaxillary and lacrimal glands, is secreted in the saliva, tears and urine. The purpose of this study was to determine if MSP is an allergen, to identify IgE-reactive proteins of different hamster species and to analyse potential cross-reactivities.
  
  
  METHODS
  Fur extracts were prepared from four hamster species. Hamster-allergic patients were selected based on a history of positive IgE-test to hamster epithelium. The IgE-reactivity of patients' sera was investigated by means of immunoblot and ELISA. IgE-reactive proteins in fur extracts and the submaxillary gland were identified using anti-MSP antibodies, Edman sequencing or mass spectrometry. MSP was purified from Golden hamster and recombinant MSP was expressed in E. coli.
  
  
  RESULTS
  Four patients had IgE-antibodies against 20.5-kDa and 24-kDa proteins of Golden hamster fur extract, which were identified as MSP. IgE-reactive MSP-like proteins were detected in European hamster fur extract. Three patient sera showed IgE-reactive bands at 17-21 kDa in Siberian and Roborovski hamster fur extracts. These proteins were identified as two closely related lipocalins. Immunoblot inhibition experiments showed that they are cross-reactive and are different from MSP.
  
  
  CONCLUSIONS
  MSP lipocalin of the Golden hamster was identified as an allergen, and it is different from the cross-reactive lipocalin allergens of Siberian and Roborovski hamsters. Our findings highlight the need for specific tools for the in vitro and in vivo diagnosis of allergy to different hamster species.
authors.affiliation: Departments of Infection and Immunity, Luxembourg Institute of Health, Luxembourg, Luxembourg.
authors.forename: Christiane
authors.initials: C
authors.lastname: Hilger
authors.forename: Ved P
authors.initials: VP
authors.lastname: Dubey
authors.forename: Delphine
authors.initials: D
authors.lastname: Lentz
authors.forename: Caroline
authors.initials: C
authors.lastname: Davril
authors.forename: Dominique
authors.initials: D
authors.lastname: Revets
authors.forename: Claude P
authors.initials: CP
authors.lastname: Muller
authors.forename: Claire
authors.initials: C
authors.lastname: Diederich
authors.forename: Hélène
authors.initials: H
authors.lastname: De La Barrière
authors.forename: Françoise
authors.initials: F
authors.lastname: Codreanu-Morel
authors.forename: Martine
authors.initials: M
authors.lastname: Morisset
authors.forename: Christiane
authors.initials: C
authors.lastname: Lehners
authors.forename: Prabir K
authors.initials: PK
authors.lastname: De
authors.forename: François
authors.initials: F
authors.lastname: Hentges
mesh_terms: D000328:Adult; D000485:Allergens / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D000818:Animals; D006224:Cricetinae; D003412:Cricetulus / Q000276:immunology; D003429:Cross Reactions; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006197:Hair / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D007073:Immunoglobulin E / Q000276:immunology; D054834:Lipocalins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D008297:Male; D008647:Mesocricetus / Q000276:immunology; D008875:Middle Aged; D017111:Phodopus / Q000276:immunology; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D012737:Sex Factors; D013045:Species Specificity; D013363:Submandibular Gland / Q000737:chemistry / Q000276:immunology*
chemical_list: D000485:Allergens; D054834:Lipocalins; D011994:Recombinant Proteins; D007073:Immunoglobulin E