Serological response (Western blot) to fractions of Mycobacterium tuberculosis sonicate antigen in tuberculosis patients and contacts.
OBJECTIVE
To assess the serological response to fractions of Mycobacterium tuberculosis sonicate antigen by Western blot analysis in patients with tuberculosis and contacts.


METHODS
We studied 71 individuals including 43 patients with active tuberculosis, 16 contacts and 12 healthy blood donors. For Western blot analysis, M. tuberculosis (H37Rv strain) sonicate antigen extract was fractionated by electrophoresis on polyacrylamide gel (SDS-PAGE).


RESULTS
We obtained antibody responses directed against four antigenic fractions with molecular weights of 71, 65, 26-38 and 19 kDa. Sixty per cent of pleural tuberculosis and 52.4% of smear-positive pulmonary tuberculosis had whole responses against all four fractions; there were no partial responses in these groups. For patients with smear-negative pulmonary tuberculosis whole responses were 17.6% and partial responses 41.2%. All contacts whose tuberculin tests converted from negative to positive (three cases) reacted exclusively against the 19 kDa fraction.


CONCLUSIONS
Western blot-positive results in patients with pleural and smear-positive pulmonary tuberculosis were characterised by a whole pattern against all four antigenic fractions, whereas patients with smear-negative pulmonary tuberculosis showed heterogeneous results. The exclusive response against the 19 kDa fraction observed in contacts with tuberculin conversion could help to identify candidates for preventive therapy.
Franco
J
J
Department of Pneumology, University Hospital Dr Peset, Valencia, Spain. jfs01v@nacom.es
Camarena
J J
JJ
Nogueira
J M
JM
Blanquer
R
R
Ruiz
M J
MJ
Marín
J
J
D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology* / Q000648:ultrastructure; D015153:Blotting, Western; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D012698:Serologic Tests; D013183:Sputum / Q000382:microbiology; D014373:Tuberculin; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis / Q000276:immunology* / Q000628:therapy
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D014373:Tuberculin