02638nas a2200421 4500000000100000008004100001260001300042653002400055653002600079653002400105653002300129653001800152653002300170653001900193653002100212653001100233653002400244653002400268653002500292653002600317653002800343653002100371653002500392653003100417653001800448100002100466700002200487700001200509700001300521700001500534700001600549700001400565245009600579300001100675490000700686520150900693022001402202 1993 d c1993 Nov10aAmino Acid Sequence10aAntibodies, Bacterial10aAntigens, Bacterial10aBacterial Proteins10aBase Sequence10aCloning, Molecular10aDNA, Bacterial10aGenes, Bacterial10aHumans10aIn Vitro Techniques10aLeprosy, Borderline10aLeprosy, lepromatous10aLymphocyte Activation10aMolecular Sequence Data10aMolecular Weight10aMycobacterium leprae10aMycobacterium tuberculosis10aT-Lymphocytes1 aRinke de Wit T F1 aClark-Curtiss J E1 aAbebe F1 aKolk A H1 aJanson A A1 aAgterveld M1 aThole J E00aA Mycobacterium leprae-specific gene encoding an immunologically recognized 45 kDa protein. a829-380 v103 a
By screening a Mycobacterium leprae lambda gt11 expression library with a serum from an Ethiopian lepromatous leprosy (LL) patient a clone was isolated (LL4) belonging to hybridization group III of a panel of previously isolated M. leprae clones. Members of this hybridization group encode a serologically recognized 45 kDa protein. The complete DNA sequences of the partially overlapping clones LL4 and L1 (hybridization group III) are presented and these revealed the presence of an open reading frame (ORF) predicting a protein with a molecular size of 42,448 Da. Southern hybridizations on total genomic DNA of M. leprae, Mycobacterium tuberculosis and eight atypical mycobacteria showed that the LL4 DNA fragment is specific for M. leprae DNA even under low-stringency conditions. The M. leprae specificity of LL4 DNA was further confirmed by the polymerase chain reaction using four different sets of primers. Western blotting analyses showed that the M. leprae 45 kDa protein is frequently recognized by antibodies from leprosy patients and that this recognition is specific since no antibodies could be detected in sera of tuberculosis patients. T-cell proliferation assays also demonstrated T-cell recognition by leprosy patients and healthy contacts of the M. leprae 45 kDa protein. The specificity of the LL4 DNA region and the 45 kDa antigen that is encoded by hybridization group III could provide unique tools for the development of M. leprae-specific immunological and DNA reagents.
a0950-382X