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Quantification of Intracellular Growth Inside Macrophages is a Fast and Reliable Method for Assessing the Virulence of Leishmania Parasites
Published on: March 16, 2018
Susceptibility to infectious diseases: Leishmania as a paradigm
R M Locksley1, S Pingel, D Lacy
1Howard Hughes Medical Institute, University of California, San Francisco 94143-0654, USA. locksley@medicine.ucsf.edu
Abstract:
The diverse response of individuals within populations to infectious pathogens remains poorly understood, although genetic determinants undoubtedly contribute in substantial ways to the outcome of infection. In a mouse model of infection with the intramacrophage protozoan Leishmania major, susceptibility correlates both with aberrant helper T cell differentiation biased towards the production of interleukin 4 and with the presence of an endogenous CD4 T cell repertoire that recognizes an immunodominant parasite antigen with high frequency. In the setting of the particular ecological niche occupied by Leishmania, this combination of otherwise unrelated factors synergizes to result in exquisite susceptibility to this single pathogen, without seemingly compromising host defenses against other agents. Similar paradigms could underlie susceptibility to other pathogenic organisms.
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