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Dominant B cell epitope region of a vespid allergen antigen 5
S140 Abstracts
J ALLERGY CLIN IMMUNOL FEBRUARY 2004
SUNDAY 459
Dominant B Cell Epitope Region of a Vespid Allergen Antigen 5
T. P. King; The Rockefeller University, New York, NY. RATIONALE: Tests with a hybrid PV1-39, containing residues 1-39 of Vv5 from yellow jacket (Vespula vulgaris) and residues 40-204 of Pa5 from paper wasp (Polistes annularis), suggest the N-terminal region to be immunodominant. This region was studied further with hybrids PV1-18 and 18-39. METHODS: Hybrids were prepared by expression in yeast. Their antigenicity was tested by binding of Vv5-specific mouse monoclonal (mc) and polyclonal (pc) Abs, immunogencity by stimulation of Vv5-specific Ab responses in mice, and allergenicity by up-regulation of cell surface marker CD203c from basophils of yellow jacket-sensitive patients. RESULTS: Two Vv5-specific mcAbs showed binding of PV1-39 and 1839 but not PV1-18, and a third mcAb showed the opposite. Hybrid antigenicity with pcAb, and hybrid immunogencity, were in the order of Vv5 > PV1-39 > PV1-18 ~ 18-39. Allergenicity data from a single patient showed a similar order and tests with additional patients are being made. CONCLUSIONS: The data with mcAbs suggest the presence of at least two adjacent epitope regions in PV-1-39. Each epitope region alone is less efficient than the bivalent PV1-39 to bind Vv5-specific pcAb as well as to stimulate such a response. The findings are relevant in the design of hybrids, with reduced allergenicity but retaining immnogenicity of natural allergen, for possible use as vaccines. Funding: ALK-Abello
J ALLERGY CLIN IMMUNOL FEBRUARY 2004
SUNDAY 459
Dominant B Cell Epitope Region of a Vespid Allergen Antigen 5
T. P. King; The Rockefeller University, New York, NY. RATIONALE: Tests with a hybrid PV1-39, containing residues 1-39 of Vv5 from yellow jacket (Vespula vulgaris) and residues 40-204 of Pa5 from paper wasp (Polistes annularis), suggest the N-terminal region to be immunodominant. This region was studied further with hybrids PV1-18 and 18-39. METHODS: Hybrids were prepared by expression in yeast. Their antigenicity was tested by binding of Vv5-specific mouse monoclonal (mc) and polyclonal (pc) Abs, immunogencity by stimulation of Vv5-specific Ab responses in mice, and allergenicity by up-regulation of cell surface marker CD203c from basophils of yellow jacket-sensitive patients. RESULTS: Two Vv5-specific mcAbs showed binding of PV1-39 and 1839 but not PV1-18, and a third mcAb showed the opposite. Hybrid antigenicity with pcAb, and hybrid immunogencity, were in the order of Vv5 > PV1-39 > PV1-18 ~ 18-39. Allergenicity data from a single patient showed a similar order and tests with additional patients are being made. CONCLUSIONS: The data with mcAbs suggest the presence of at least two adjacent epitope regions in PV-1-39. Each epitope region alone is less efficient than the bivalent PV1-39 to bind Vv5-specific pcAb as well as to stimulate such a response. The findings are relevant in the design of hybrids, with reduced allergenicity but retaining immnogenicity of natural allergen, for possible use as vaccines. Funding: ALK-Abello