Cloning and sequence analysis of genes encoding Fasciola hepatica immunodominant antigens.
Fasciola hepatica lambdagt11 cDNA expression library was immuno-screened with IPAb, two clones were isolated and identified as Fhlambda400 Fhlambda800. Both clones were sequenced, FhA400 contained 305 translated bases encoding 11.509 kDa and designated as SFh12, while Fhlambda800 contained 311 translated bases encoding protein of 11.058 kDa designated as SFh11. The DNA sequence homology search of Fhlambda400 revealed a relatively high degree of identity with F. hepatica amoebapore-like protein mRNA (GenBank accession No. AF286903). However, Fhlambda800 revealed the highest similarity with F. hepatica tegumental antigen (T1) mRNA (GenBank accession No. AF153056). The protein homology search of SFh12 gave 100% identity with amoebapore-like protein (APLP), while SFh-\11 showed 75% identity with F. hepatica tegumenttal antigen (TA). The biochemical analysis of the deduced proteins was identified; in addition the predicted T- & B-cell epitopes have been also evaluated. However, histological localization of identified antigens was achieved using the IPAb in an indirect immunoflorescent antibody assay (IFA). Results revealed that the IPAb labeled the outer glycocalyx in a characteristic, pattern, which proved that the identified antigens were tegumental in origin and that infected Fasciola subjects induced antibodies directed mainly against tegumental components.
Mohamed
Mona M
MM
Department of Zoology, Faculty of Science, Cairo University, Cairo, Egypt. monamos@hotmail.com
Al-Sherbiny
Maged M
MM
Araf
Abla A Sh
AA
Elmamlouk
Tahani H
TH
D000595:Amino Acid Sequence; D000818:Animals; D000947:Antigens, Helminth / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D003001:Cloning, Molecular; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D018985:Epitopes, B-Lymphocyte / Q000235:genetics / Q000276:immunology; D018984:Epitopes, T-Lymphocyte / Q000235:genetics / Q000276:immunology; D005210:Fasciola hepatica / Q000235:genetics* / Q000276:immunology*; D017238:Genes, Helminth / Q000235:genetics*; D016056:Immunodominant Epitopes / Q000235:genetics* / Q000276:immunology; D008969:Molecular Sequence Data; D016415:Sequence Alignment
D000947:Antigens, Helminth; D018509:DNA, Helminth; D018985:Epitopes, B-Lymphocyte; D018984:Epitopes, T-Lymphocyte; D016056:Immunodominant Epitopes