Understanding eco-immunology of bacterial zoonoses and alternative therapeutics toward "One Health"

The current review identifies key bacterial zoonoses, the understanding of comparative immunology, evolutionary trade-offs between emerging bacterial pathogens and their dynamics on both arms of immunity. The several gaps in the literature limit our understanding of spread of prominent bacterial zoonotic diseases and the host-pathogen interactions that may change in response to environmental and social factors. Gaining a more comprehensive understanding of how anthropogenic activities affects the spread of emerging zoonotic diseases, is essential for predicting and mitigating future disease emergence through fine-tuning of surveillance and control measures with respect to different pathogens. This review highlights the urgent need to increase understanding of the comparative immunity of animal reservoirs, design of vaccines according to the homology in host-pathogen interactions, and the alternative strategies to counter the risk of bacterial pathogenic spillover to humans with eventual spread of zoonotic diseases.

Do Life History Traits Influence Patterns of Maternal Immune Elements in New World Blackbirds (Icteridae)?

Avian immunology developed originally by investigating domesticated poultry species (Galliformes), but in recent decades eco-immunological studies of wild bird species have revealed that avian immune systems are more diverse than initially assumed. This study compares six immunological elements in eggs of six species within the same family, the New World blackbirds (Icteridae),whose members differ most notably in two life history parameters, brood parasitism and body size. We measured the maternal immune investment of passive immune components in both yolk and albumen: lysozyme, ovotransferrin, and immunoglobulins (Igs), and LPS-specific Igs. We predicted that brood parasites would have higher levels of immune activity for both innate and adaptive immunity compared with non-brood parasites, and that increased body size could increase microbial exposure of larger animals, resulting in an increase in some adaptive immune responses, such as LPS-specific Igs. We found that brood parasites had significantly higher levels of Igs and lysozyme levels in albumen, but significantly lower levels of Igs in yolk compared with non-brood parasites. Igs in yolk scaled according to body size, with the smallest organisms (the brood parasites) having the lowest levels, and the largest organism (common grackle) having the highest. Our results confirm the findings of other studies of comparative immunity among species in a single taxon that (1) similarities in immune investment cannot be assumed among closely related species and (2) single measures of immune defense cannot be assumed to be indicators of a species’ overall immune strategy, as life history traits can differentially affect immune responses.

Molecular characterization and expression analysis of the NLR family CARD containing five transcripts in the pig

The NOD-like receptor (NLR) family caspase recruitment domain-containing 5 (NLRC5) is one of the newly discovered and largest NLR family members. The NLRC5 has recently received extensive attention because of its important role in regulating innate and adaptive immune responses. The NLRC5 in many vertebrates, such as humans, mice, cattle, and horses, has already been proven and studied. However, the NLRC5 gene characteristics of pigs remain unclear. Thus, we completely cloned the NLRC5 cDNA sequence of the pig using the rapid amplification of cDNA ends(RACE) technology. A characteristic and tissue expression analysis was also conducted on the pig sequence. The sequence analysis showed that the complete cDNA sequence of the NLRC5 of the pig is 6638 bp, and the open reading frame is 5538 bp which encoded 1846 amino acids. The protein prediction analysis indicates that the overall performance of the NLRC5 protein of the pig is hydrophilic and possesses a typical nucleotide binding and oligomerization domain(NBD) and 20 leucine-rich repeats(LRRs). The homology analysis result indicates that the NLRC5 transcript in pigs is highly homologous to cattle, sheep, macaques, and humans, and accounts for around 80%. The genetic evolutionary tree analysis shows that the NLRC5 transcript in pigs has the closest evolutionary relationship with cattle and sheep. Further tissue expression analysis shows that immune organ systems (e.g., lymph node and spleen) and mucosa organs (e.g., intestinal lymph node, stomach, and lungs) possess high expressions with NLRC5 mRNA. The result of this study indicates that the NLRC5 transcript in pigs is relatively conservative among mammals and may play a vital role in immune reaction, which provides a basis for further studies on the NLRC5 function in the pig immune system and the role in comparative immunity.