SETTING: Rural northern Malawi, where vaccination with BCG Glaxo (1077) provides protection against leprosy but not against pulmonary tuberculosis. OBJECTIVE: To evaluate the patterns of responsiveness to purified protein derivative of Mycobacterium tuberculosis (PPD) in terms of delayed type hypersensitivity (DTH) and interferon-gamma (IFN-gamma) production. DESIGN: IFN-gamma was measured in 6 day whole blood cultures diluted 1 in 10, stimulated with PPD RT48, and the results compared to the DTH response to PPD RT23. A total of 633 individuals aged 12 to 28 years, without prior BCG vaccination, were recruited. RESULTS: Overall, 63% of subjects made a positive IFN-gamma response (defined as >62 pg/ml), and 37% gave a DTH induration of >5 mm. A strong correlation between skin test and IFN-gamma responses was observed, although with interesting exceptions: 13/270 individuals with zero DTH showed IFN-gamma responses >500 pg/ml, and 7/53 individuals with >10 mm induration showed IFN-gamma responses < or = 62 pg/ml. The prevalence of skin test responsiveness increased with age, and was higher among older males than females; age-sex patterns were less clear for IFN-gamma production. CONCLUSION: The 6 day IFN-gamma response to PPD correlates well with Mantoux skin test induration. The discordant individuals may represent important subsets in terms of protective immunity and risk of clinical tuberculosis.
SETTING: Rural northern Malawi, where vaccination with BCG Glaxo (1077) provides protection against leprosy but not against pulmonary tuberculosis. OBJECTIVE: To evaluate the patterns of responsiveness to purified protein derivative of Mycobacterium tuberculosis (PPD) in terms of delayed type hypersensitivity (DTH) and interferon-gamma (IFN-gamma) production. DESIGN: IFN-gamma was measured in 6 day whole blood cultures diluted 1 in 10, stimulated with PPD RT48, and the results compared to the DTH response to PPD RT23. A total of 633 individuals aged 12 to 28 years, without prior BCG vaccination, were recruited. RESULTS: Overall, 63% of subjects made a positive IFN-gamma response (defined as >62 pg/ml), and 37% gave a DTH induration of >5 mm. A strong correlation between skin test and IFN-gamma responses was observed, although with interesting exceptions: 13/270 individuals with zero DTH showed IFN-gamma responses >500 pg/ml, and 7/53 individuals with >10 mm induration showed IFN-gamma responses < or = 62 pg/ml. The prevalence of skin test responsiveness increased with age, and was higher among older males than females; age-sex patterns were less clear for IFN-gamma production. CONCLUSION: The 6 day IFN-gamma response to PPD correlates well with Mantoux skin test induration. The discordant individuals may represent important subsets in terms of protective immunity and risk of clinical tuberculosis.
Authors: S A Sharpe; H McShane; M J Dennis; R J Basaraba; F Gleeson; G Hall; A McIntyre; K Gooch; S Clark; N E R Beveridge; E Nuth; A White; A Marriott; S Dowall; A V S Hill; A Williams; P D Marsh Journal: Clin Vaccine Immunol Date: 2010-06-09
Authors: Lerisa Govender; Brian Abel; E Jane Hughes; Thomas J Scriba; Benjamin M N Kagina; Marwou de Kock; Gerhard Walzl; Gillian Black; Ida Rosenkrands; Gregory D Hussey; Hassan Mahomed; Peter Andersen; Willem A Hanekom Journal: Vaccine Date: 2010-10-23 Impact factor: 3.641
Authors: S M B Jeronimo; A K B Holst; S E Jamieson; R Francis; D R A Martins; F L Bezerra; N A Ettinger; E T Nascimento; G R Monteiro; H G Lacerda; E N Miller; H J Cordell; P Duggal; T H Beaty; J M Blackwell; M E Wilson Journal: Genes Immun Date: 2007-08-23 Impact factor: 2.676
Authors: Rosemary E Weir; Gillian F Black; Hazel M Dockrell; Sian Floyd; Paul E M Fine; Steven D Chaguluka; Sally Stenson; Elizabeth King; Bernadette Nazareth; David K Warndorff; Bagrey Ngwira; Amelia C Crampin; Lorren Mwaungulu; Lifted Sichali; Elizabeth Jarman; Linda Donovan; Jenefer M Blackwell Journal: Infect Immun Date: 2004-03 Impact factor: 3.441