Protein sequence analysis and mapping of IgE and IgG epitopes of an allergenic 98-kDa Dermatophagoides farinae paramyosin, Der f 11.
BACKGROUND
A 98-kDa mite paramyosin (Der f 11) from Dermatophagoides farinae (Df) is highly allergenic, and its cDNA (Df642) has been cloned. This paper describes the sequence characteristics and the mapping of the immunodominant human IgE and IgG epitopes of Der f 11.


METHODS
The protein sequence analysis was performed with a combination of FASTA, GCG, and CLUSTAL W computing packages. The whole cDNA insert and its PCR-derived DNA fragments were generated and expressed in E. coli. These overlapping recombinant peptides (F1 to F5) were used for B-cell epitope mapping with 18 mite-allergic sera by dot immunoassays.


RESULTS
Df642 cDNA encodes a partial sequence that contains the 2nd to 26th 28-residue repeats and lacks the N-terminus and the C-terminus. The sequence identity of Der f 11 with other known paramyosins is 34-60%. The dominant IgE epitopes are located in peptides F1 and F4, whereas the dominant IgG epitopes are located in peptides F1 and F2. These peptides are more reactive than whole rDf642.


CONCLUSIONS
Mite paramyosin is very similar to other known paramyosins. The human IgE and IgG epitopes are scattered throughout the entire molecule. Data also indicate the presence of unique IgE and IgG epitopes in Der f 11.
Tsai
L C
LC
Department of Medical Research, Veterans General Hospital, Taipei, Taiwan.
Chao
P L
PL
Hung
M W
MW
Sun
Y C
YC
Kuo
I C
IC
Chua
K Y
KY
Liaw
S H
SH
Chua
K Y
KY
Kuo
I C
IC
D000485:Allergens / Q000235:genetics* / Q000276:immunology; D000818:Animals; D000915:Antibody Affinity; D039741:Antigens, Dermatophagoides; D001483:Base Sequence; D000939:Epitopes / Q000235:genetics* / Q000276:immunology; D006023:Glycoproteins / Q000235:genetics / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000235:genetics*; D007074:Immunoglobulin G / Q000235:genetics* / Q000276:immunology; D008925:Mites / Q000235:genetics / Q000276:immunology; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein; D014335:Tropomyosin / Q000235:genetics* / Q000276:immunology
D000485:Allergens; D039741:Antigens, Dermatophagoides; D000939:Epitopes; D006023:Glycoproteins; D007074:Immunoglobulin G; D014335:Tropomyosin; D007073:Immunoglobulin E