Resolution of an Infection with Leishmania braziliensis Confers Complete Protection to a Subsequent Challenge with Leishmania major in BALB/c Mice

Both Leishmania major and L. braziliensis induce cutaneous leishmaniasis in BALB/c mice. Whereas BALB/c mice die of infection with L. major, they cure an infection with L. braziliensis. We report here that after curing an infection with L. braziliensis, BALB/c mice are resistant to challenge with L. major. When challenged with L. major, L. braziliensis pre-treated BALB/c mice mounted a delayed-type hypersensitivity response to L. major and produced high amounts of interferon-g (IFN-g ) but low amounts of interleukin-4. The IFN-g produced by the L. braziliensis pre-infected mice was involved in the protection seen against L. major challenge since treating the mice with a neutralizing anti-IFN-g abrogated the protection. This suggests that cross-reactive antigen epitopes exist between L. braziliensis and L. major and that pre-infection with L. braziliensis primes BALB/c mice to epitopes on L. major that can elicit a protective Th1 response to the parasite.

M. Deffert [i. e. Henry Defert], président du T. C. F. [Touring-Club de France] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 56902

M. Deffert [i. e. Henry Defert], président du T. C. F. [Touring-Club de France] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 56901

M. Deffert [i. e. Henry Defert] président [du] T. C. F. [Touring-Club de France] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 56900

[M. Henry Defert président du Touring-Club de France] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 56899

Max Henry [boxeur] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 55120

Max Henry [boxeur] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 55119

Colonel Bermont [i. e. Pavel Rafalovich Bermondt-Avalov commandant des troupes russo-allemandes de la Baltique] avec les officiers de son état-major à Berlin : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57303

Major Empson sur AV, pesage de Paris-Nice [cycle-car, 1100 cmc, course Paris-Nice] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 57958

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.