The integration of chromatin modifiers into specific regulatory networks is not fully understood. In this issue of Immunity, Austenaa et al. (2012) demonstrate a specific role for the histone methyltransferase MLL4 (Wbp7) in controlling the expression of critical molecules in the Toll-like receptor pathway.

Polymorphonuclear leukocytes (PMNs or neutrophils) are an essential component of the human innate immune system. Circulating neutrophils are rapidly recruited to sites of infection by host- and/or pathogen-derived components, which also prime these host cells for enhanced microbicidal activity. PMNs bind and ingest microorganisms by a process known as phagocytosis, which typically triggers prod...

The innate immune system is the only defense weapon that invertebrates have, and it is the fundamental defense mechanism for fish. The innate immune response is important in newly hatched flounders because it is closely involved in the initial feeding phase, which is why it is essential for survival during the juvenile period. The expression analysis of genes involved in the innate immune respo...

Studies in mammals uncovered important signaling roles of nitric oxide (NO), and contributions to innate immunity. Suggestions of conservation led us to explore the involvement of NO in Drosophila innate immunity. Inhibition of nitric oxide synthase (NOS) increased larval sensitivity to gram-negative bacterial infection, and abrogated induction of the antimicrobial peptide Diptericin. NOS was u...

The developmental environment can have lasting effects on posthatching phenotype in oviparous animals. Innate immune response is one important component of fitness in vertebrates because it provides a generalized defense against infection. In addition, because male vertebrates are at a higher risk of infection than females, males may benefit more from increased innate immunity than females. We ...

The innate immune response is evolutionary conserved among organisms. The complement system forms an important and efficient immune defense mechanism. It consists of plasma proteins that participate in microbial detection, which ultimately results in the production of various molecules with antimicrobial activity. Thioester-containing proteins (TEPs) are a superfamily of secreted effector prote...

Innate immunity is an evolutionarily ancient defense system that enables animals and plants to resist invading microorganisms. Recent studies have demonstrated the existence of innate immune responses in Caenorhabditis elegans.

During infections, the first reaction of the host against microbial pathogens is carried out by innate immune cells, which recognize conserved structures on pathogens, called pathogen-associated molecular patterns. Afterward, some of these innate cells can phagocytose and destroy the pathogens, secreting cytokines that would modulate the immune response to the challenge. This rapid response is ...

Interleukin (IL)-26 is released in response to bacterial endotoxin (LPS) in the bronchoalveolar space of humans in vivo and it may potentiate neutrophil chemotaxis by enhanced IL-26 receptor stimulation. However, the effects of extracellular IL-26 protein on the innate immune response in the lungs in vivo remain unknown. Here, we characterized these effects of IL-26 on a wide range of aspects o...

Despite the development of new treatments, the mortality due to invasive pulmonary aspergillosis remains above 50%, reaching 95% in certain situations. The battle against Aspergillus fumigatus involves several components of the pulmonary innate immune system: cells, mediators, and natural antifungal molecules involved in the recognition and elimination of the fungus, thereby preventing coloniza...