Article

A Specific Primed Immune Response in Drosophila Is Dependent on Phagocytes

Department of Microbiology and Immunology, Stanford University, Stanford, California, United States of America.
PLoS Pathogens (Impact Factor: 8.06). 04/2007; 3(3):e26. DOI: 10.1371/journal.ppat.0030026
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ABSTRACT Author Summary

Due to the common practice of vaccination and prominence of AIDS, people are already aware of the distinction between adaptive and innate immunity without realizing it. All organisms have an innate immune response, but only vertebrates possess T cells and the ability to produce antibodies. It has been a long-standing assumption that invertebrate immune systems are not adaptive and respond identically to multiple challenges. In this study, we demonstrate that the fly innate immune response adapts to repeated challenges; flies preinoculated with dead Streptococcus pneumoniae are protected against a second, otherwise-lethal dose. Although the underlying mechanisms are likely to be very different, this primed response is reminiscent to vaccine-induced protection in that it exhibits coarse specificity (dead S. pneumoniae only protects against itself), persists for the life of the fly and is dependent on phagocytic cells. This result prompts the obvious question of whether the innate immune system of vertebrates shares a similar biology. Such a finding is of particular interest since immunocompromised individuals only possess an innate immune system.

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    • "In some animals, pathogen challenge increases resistance to subsequent infections (a pattern referred to as immune priming, see Pham et al. 2007; Lawniczak et al. 2007; Roth et al. 2009); but, in other animals, it enhances aspects of physiology, often to the detriment of their ability to fight off subsequent live infections (Leroy et al. 2012; Papp et al. 2012; Ermolaeva et al. 2013). Although it is unknown whether the physiological benefits of pathogen challenges fulfill the characteristic pattern of hormesis (an inverted " U " dose–response relationship with beneficial effects at low doses and toxic effects at high doses), the finding that life-history traits can be improved by a single dose of pathogen challenge suggests that hormesis can be induced by host responses to pathogen challenge (Leroy et al. 2012; Papp et al. 2012; Ermolaeva et al. 2013). "
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    Evolution 05/2014; 68(8). DOI:10.1111/evo.12453 · 4.66 Impact Factor
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    • "As we used a B. bassiana strain isolated from our study site of F. selysi (Reber and Chapuisat 2012b), it is possible that the pathogen has co-evolved with its host and thus is able to evade the immune response in F. selysi, but not in L. niger (e.g., Schmid-Hempel 2009). Whatever the reason , immune priming is likely to depend on many factors such as host and pathogen species, host conditions, pathogen dose, and virulence (this study; Pham et al. 2007; Gonz alez-Tokman et al. 2010; Reber and Chapuisat 2012a "
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    Ecology and Evolution 05/2014; 4(10). DOI:10.1002/ece3.1070 · 1.66 Impact Factor
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    • "Although there have been more and more research on the immune priming of invertebrate, most of the previous studies have concentrated on the reduced mortality to evaluate the enhanced immune protection . It was demonstrated in Drosophila melanogaster Meigen (Diptera: Drosophilidae) that the protective effect of immune priming to Streptococcus pneumoniae infection depended on the phagocytes and Toll pathway (Pham et al. 2007). Recently, Roth and Kurtz (2009) demonstrated that phagocytic activity of the woodlouse Porcellio scaber Latreille (Isopoda: Porcellionidae ) was increased in a pathogen-speciÞc manner after priming. "
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