BACKGROUND: Allergenic components from Blomia tropicalis are important triggers of allergies in the tropics. OBJECTIVE: We sought to identify and characterize a novel allergen, Blo t 21, from B tropicalis. METHODS: Blo t 21 was initially identified from an expressed sequence tag database generated from a B tropicalis cDNA library. Allergenicity of this antigen was examined by means of skin prick testing, ELISA, and IgE immuno-dot blotting. We evaluated whether Blo t 21 and Blo t 5 were cross-reactive by using IgE inhibition ELISAs. RESULTS: Blo t 21, a 129-amino-acid protein sharing 39% identity with Blo t 5, is a product of a single-copy gene. It has an alpha-helical secondary structure and localizes to midgut and hindgut contents of B tropicalis, as well as fecal particles. Positive responses to Blo t 21 were shown in 93% (40/43) by means of ELISA and 95% (41/43) by means of skin prick testing when assayed in 43 adult patients with ongoing persistent allergic rhinitis. However, sera of 494 consecutive individuals attending outpatient allergy clinics over 1(1/2) years showed 57.9% (286/494) had positive responses to Blo t 21. Although the majority (>75%) of sensitized individuals were cosensitized to both Blo t 5 and Blo t 21, these 2 allergens had a low-to-moderate degree of cross-reactivity. CONCLUSION: Blo t 21 is a major allergen in B tropicalis that is not highly cross-reactive to Blo t 5, despite sharing some sequence and structural identity. CLINICAL IMPLICATIONS: Blo t 21, representing a new group of allergens, is an important B tropicalis allergen.
BACKGROUND: Allergenic components from Blomia tropicalis are important triggers of allergies in the tropics. OBJECTIVE: We sought to identify and characterize a novel allergen, Blo t 21, from B tropicalis. METHODS: Blo t 21 was initially identified from an expressed sequence tag database generated from a B tropicalis cDNA library. Allergenicity of this antigen was examined by means of skin prick testing, ELISA, and IgE immuno-dot blotting. We evaluated whether Blo t 21 and Blo t 5 were cross-reactive by using IgE inhibition ELISAs. RESULTS: Blo t 21, a 129-amino-acid protein sharing 39% identity with Blo t 5, is a product of a single-copy gene. It has an alpha-helical secondary structure and localizes to midgut and hindgut contents of B tropicalis, as well as fecal particles. Positive responses to Blo t 21 were shown in 93% (40/43) by means of ELISA and 95% (41/43) by means of skin prick testing when assayed in 43 adult patients with ongoing persistent allergic rhinitis. However, sera of 494 consecutive individuals attending outpatientallergy clinics over 1(1/2) years showed 57.9% (286/494) had positive responses to Blo t 21. Although the majority (>75%) of sensitized individuals were cosensitized to both Blo t 5 and Blo t 21, these 2 allergens had a low-to-moderate degree of cross-reactivity. CONCLUSION: Blo t 21 is a major allergen in B tropicalis that is not highly cross-reactive to Blo t 5, despite sharing some sequence and structural identity. CLINICAL IMPLICATIONS: Blo t 21, representing a new group of allergens, is an important B tropicalis allergen.
Authors: Luis Caraballo; Josefina Zakzuk; Bee Wah Lee; Nathalie Acevedo; Jian Yi Soh; Mario Sánchez-Borges; Elham Hossny; Elizabeth García; Nelson Rosario; Ignacio Ansotegui; Leonardo Puerta; Jorge Sánchez; Victoria Cardona Journal: World Allergy Organ J Date: 2016-06-27 Impact factor: 4.084
Authors: Sze Lei Pang; Kok Lian Ho; Jitka Waterman; Aik Hong Teh; Fook Tim Chew; Chyan Leong Ng Journal: Acta Crystallogr F Struct Biol Commun Date: 2015-10-23 Impact factor: 1.056
Authors: Kellyanne dos Anjos Carvalho; Osvaldo Pompílio de Melo-Neto; Franklin Barbalho Magalhães; João Carlos Marques Ponte; Filipe Adriano Borba Felipe; Mariese Conceição Alves dos Santos; Givaneide dos Santos Lima; Álvaro Augusto Cruz; Carina Silva Pinheiro; Lain Carlos Pontes-de-Carvalho; Neuza Maria Alcantara-Neves Journal: BMC Immunol Date: 2013-02-27 Impact factor: 3.615