Immunoscreening of Schistosoma japonicum egg cDNA library.
OBJECTIVE
To screen and identify genes encoding vaccine candidates and molecules with diagnostic potential from S. japonicum (S. j) egg cDNA library.


METHODS
S. j egg cDNA library was screened by sera from SEA-immunized rabbits. Positive clones were identified after three rounds of screening and were excised automatically in vivo with helper phage. Products of PCR were used to detect insert sizes by agarose gel electrophoresis. DNA samples were obtained by purification using mini-prep kit. Automatic sequencing was carried out and the sequence data were analysed using GCG software.


RESULTS
Twelve clones were identified as positive and the inserts were around 1.2 kb in size. Compared with DNA sequences in GenBank, eight clones were homologous to a 70 kDa S. j heatshock protein(S. j HsP70). C18 exhibited 97.8% homology with S. j23. C22 and C23 shared 82.4% and 89.5% homology with S. j calreticulin, respectively. C12 was homologous to S. mansoni(S. m.) immunophilin.


CONCLUSIONS
This paper first reported the results of immunoscreening S. j egg cDNA library by anti-SEA sera. Twelve positive clones were found to be related to protective immunity and/or immunodiagnosis of schistosomiasis.
Zhou
J
J
Department of Parasitology, Hunan Medical University, Changsha 410078.
Yi
X
X
Zeng
Q
Q
Zhang
S
S
Cai
C
C
D000818:Animals; D000947:Antigens, Helminth / Q000235:genetics; D018509:DNA, Helminth / Q000235:genetics; D015723:Gene Library; D017238:Genes, Helminth; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics; D015801:Helminth Proteins; D008565:Membrane Proteins / Q000235:genetics; D010063:Ovum; D012549:Schistosoma japonicum / Q000235:genetics* / Q000276:immunology; D012689:Sequence Homology, Nucleic Acid
D000947:Antigens, Helminth; D018509:DNA, Helminth; D018840:HSP70 Heat-Shock Proteins; D015801:Helminth Proteins; D008565:Membrane Proteins; C072633:Sj23 antigen, Schistosoma japonicum