Defense peptides secreted by helminth pathogens: antimicrobial and/or immunomodulator molecules?

Host defense peptides (HDPs) are an evolutionarily conserved component of the innate immune response found in all living species. They possess antimicrobial activities against a broad range of organisms including bacteria, fungi, eukaryotic parasites, and viruses. HDPs also have the ability to enhance immune responses by acting as immunomodulators. We discovered a new family of HDPs derived from pathogenic helminth (worms) that cause enormous disease in animals and humans worldwide. The discovery of these peptides was based on their similar biochemical and functional characteristics to the human defense peptide LL-37. We propose that these new peptides modulate the immune response via molecular mimicry of mammalian HDPs thus providing a mechanism behind the anti-inflammatory properties of helminth infections.

Innate host defense functions of secretory leucoprotease inhibitor

Chronic lung diseases such as cystic fibrosis and emphysema are characterized by a protease burden, an infective process and a dominant proinflammatory profile. Secretory leucoprotease inhibitor (SLPI) is a prominent innate immune protein of the respiratory tract, possessing serine protease inhibitor activity, antibacterial activity, and anti-inflammatory/immunomodulatory activity. In the course of this review, the authors highlight the findings from a range of studies that illustrate the multiple functions of SLPI and its role in the resolution of the immune response.

Exploring the Transcriptome of Atlantic Salmon (Salmo salar) Skin, a Major Defense Organ

The skin of fish is the first line of defense against pathogens and parasites. The skin transcriptome of the Atlantic salmon is poorly characterized, and currently only 2,089 expressed sequence tags (ESTs) out of a total of half a million sequences are generated from skin-derived cDNA libraries. The primary aim of this study was to enhance the transcriptomic knowledge of salmon skin by using next-generation sequencing (NGS) technology, namely the Roche-454 platform. An equimolar mixture of high-quality RNA from skin and epidermal samples of salmon reared in either freshwater or seawater was used for 454-sequencing. This technique yielded over 600,000 reads, which were assembled into 34,696 isotigs using Newbler. Of these isotigs, 12 % had not been sequenced in Atlantic salmon, hence representing previously unreported salmon mRNAs that can potentially be skin-specific. Many full-length genes have been acquired, representing numerous biological processes. Mucin proteins are the main structural component of mucus and we examined in greater detail the sequences we obtained for these genes. Several isotigs exhibited homology to mammalian mucins (MUC2, MUC5AC and MUC5B). Mucin mRNAs are generally > 10 kbp and contain large repetitive units, which pose a challenge towards full-length sequence discovery. To date, we have not unearthed any full-length salmon mucin genes with this dataset, but have both N- and C-terminal regions of a mucin type 5. This highlights the fact that, while NGS is indeed a formidable tool for sequence data mining of non-model species, it must be complemented with additional experimental and bioinformatic work to characterize some mRNA sequences with complex features.

The overlap between war and crime: unpacking Foucault and Agamben’s studies within the context of the war on terror

This article will consider the current convergence between war and crime by unpacking Foucault’s analysis of power and Agamben’s elaboration on the conjunction between the banning of a life and the constitution of the polity. It will show that these perspectives link together crime and war as mechanisms that contribute to the governance of the population by legitimating authority and their use of force through the military and the police while excluding part of the population. It will expose how these convergences highlight the problem of the political in the constitution of the social order at the global level. In the current contingency, crime and war are strongly implicated in the crucial political function of calling people to share their similarities and differences, and yet are not the best mechanisms for dealing with the sharing of a world in common.