Premium
Lack of serological specificity of recombinant heat shock protein of Leishmania donovani
Author(s) -
ARORA SUNIL K,
MELBY PETER C,
SEHGAL SHOBHA
Publication year - 1995
Publication title -
immunology and cell biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.999
H-Index - 104
eISSN - 1440-1711
pISSN - 0818-9641
DOI - 10.1038/icb.1995.69
Subject(s) - recombinant dna , biology , complementary dna , microbiology and biotechnology , serology , cdna library , virology , leishmania donovani , antigen , antibody , visceral leishmaniasis , gene , leishmaniasis , genetics
Summary In order to identify a specific recombinant antigen of Leishmania donovani with potential use for diagnosis, a cDNA library was constructed in lambda ZAP II expression vector. On screening the cDNA library using pooled sera from Indian patients with kala azar, 20 antibody reactive clones were identified. These were subcloned into pBluescript phagemid by an in vivo excision procedure. The molecular weights of the expressed recombinant proteins varied from 15 to 70 kDa and the cDNA insert sizes varied from 0.5 kb to the largest size of approximately 2.0 kb which was designated as the E2b clone. The nucleotide sequencing revealed that 50% of the clones had sequence homology to the heat shock protein gene of L. donovani. The serological studies conducted with the kala azar positive sera and sera from healthy laboratory workers using the recombinant protein from the E2b clone and having sequence homology to Ldhsp 70, indicated that although all the kala azar sera were positive, 12 of 20 healthy individuals also showed antibodies against the recombinant hsp70, indicating that this antigen is not suitable for serological diagnosis of kala azar.