Early treatment during a primary malaria infection modifies the development of cross immunity
Por:
Legorreta-Herrera M., Ventura-Ayala M.L., Licona-Chávez R.N., Soto-Cruz I., Hernández-Clemente F.F.
Publicada:
1 ene 2004
Resumen:
We have used a murine model to study the kinetics of cross-protection when a primary infection is halted at different times. We analysed how parasitaemia is modified during a second infection with the homologous parasite, a heterologous parasite, or a mixture of the two. In addition, possible mechanisms involved in cross-protection were analysed. Results show that treatment with pyrimethamine on day 5 during a primary infection with P. chabaudi AS (non-lethal), prevents the generation of cross-protection to a new challenge with lethal P. yoelii 17XL. In contrast, when treatment is on day 7, mice survive a P. yoelii infection. Differences between both groups suggest that in order for 'preimmune' mice to survive a lethal challenge, a predominantly TH2-type response is required, with a higher mRNA expression level of IL-4 and IL-10, and a lower mRNA expression of IFN-?. This work shows that an early treatment of a malaria infection produced by a non-lethal parasite drives the immune response towards a loss of cross-protection to further infections, in particular with more virulent parasites. This finding should be taken into account for the development of effective malaria vaccines.
Filiaciones:
Legorreta-Herrera M.:
Lab. de Immunología Molecular, Fac. de Estudios Superiores Zaragoza, Univ. Nac. Autónomia de Mex., Iztapalapa, Mexico
Lab. de Immunología Molecular, FES Zaragoza, UNAM, Batalla 5 Mayo esq. Fuerte de Loreto, Ejercito Oriente 09320, Itzapalapa, Mexico
Ventura-Ayala M.L.:
Lab. de Immunología Molecular, Fac. de Estudios Superiores Zaragoza, Univ. Nac. Autónomia de Mex., Iztapalapa, Mexico
Licona-Chávez R.N.:
Lab. de Immunología Molecular, Fac. de Estudios Superiores Zaragoza, Univ. Nac. Autónomia de Mex., Iztapalapa, Mexico
Soto-Cruz I.:
Lab. de Immunología Molecular, Fac. de Estudios Superiores Zaragoza, Univ. Nac. Autónomia de Mex., Iztapalapa, Mexico
Hernández-Clemente F.F.:
Lab. de Immunología Molecular, Fac. de Estudios Superiores Zaragoza, Univ. Nac. Autónomia de Mex., Iztapalapa, Mexico
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