Missing in action —The meaning of cell death in tissue damage and inflammation
Summary
Billions of cells die every day in higher organisms as part of the normal process of tissue homeostasis. During special conditions like in development, acute infections, mechanical injuries, and immunity, cell death is a common denominator and it exerts profound effects in the outcome of these scenarios. To prevent the accumulation of aged, superfluous, infected, damaged and dead cells, professional phagocytes act in a rapid and efficient manner to clear the battle field and avoid spread of the destruction. Neutrophils are the most abundant effector immune cells that extravasate into tissues and can turn injured ti...
Source: Immunological Reviews - October 13, 2017 Category: Allergy & Immunology Authors: Luis E. Mu ñoz, Moritz Leppkes, Tobias A. Fuchs, Markus Hoffmann, Martin Herrmann Tags: INVITED REVIEW Source Type: research
Death begets a new beginning
Summary
Cell death is a perpetual feature of tissue microenvironments; each day under homeostatic conditions, billions of cells die and must be swiftly cleared by phagocytes. However, cell death is not limited to this natural turnover—apoptotic cell death can be induced by infection, inflammation, or severe tissue injury. Phagocytosis of apoptotic cells is thus coupled to specific functions, from the induction of growth factors that can stimulate the replacement of dead cells to the promotion of tissue repair or tissue remodeling in the affected site. In this review, we outline the mechanisms by which phagocytes sense ap...
Source: Immunological Reviews - October 13, 2017 Category: Allergy & Immunology Authors: Lidia Bosurgi, Lindsey D. Hughes, Carla V. Rothlin, Sourav Ghosh Tags: INVITED REVIEW Source Type: research
Death, danger & immunity: Fundamental mechanisms linking pathogenic or iatrogenic cell death events to immune responses
(Source: Immunological Reviews)
Source: Immunological Reviews - October 13, 2017 Category: Allergy & Immunology Authors: Guido Kroemer Tags: INTRODUCTION Source Type: research
Issue Information
(Source: Immunological Reviews)
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Tags: ISSUE INFORMATION Source Type: research
Competing forces maintain the Hydra metaorganism
Summary
Our conventional view of multicellular organisms often overlooks the fact that they are metaorganisms. They consist of a host, which is comprised of both a community of self‐replicating cells that can compete as well as cooperate and a community of associated microorganisms. This newly discovered complexity raises a profound challenge: How to maintain such a multicellular association that includes independently replicating units and even different genotypes? Here, we identify competing forces acting at the host tissue level, the host‐microbe interface, and within the microbial community as key factors to mainta...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Peter Deines, Tim Lachnit, Thomas C. G. Bosch Tags: INVITED REVIEW Source Type: research
A bacteriophages journey through the human body
Summary
The human body is colonized by a diverse collective of microorganisms, including bacteria, fungi, protozoa and viruses. The smallest entity of this microbial conglomerate are the bacterial viruses. Bacteriophages, or phages for short, exert significant selective pressure on their bacterial hosts, undoubtedly influencing the human microbiome and its impact on our health and well‐being. Phages colonize all niches of the body, including the skin, oral cavity, lungs, gut, and urinary tract. As such our bodies are frequently and continuously exposed to diverse collections of phages. Despite the prevalence of phages th...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Jeremy J. Barr Tags: INVITED REVIEW Source Type: research
The intestinal microbiota: Antibiotics, colonization resistance, and enteric pathogens
Summary
The human gastrointestinal tract hosts a diverse network of microorganisms, collectively known as the microbiota that plays an important role in health and disease. For instance, the intestinal microbiota can prevent invading microbes from colonizing the gastrointestinal tract, a phenomenon known as colonization resistance. Perturbations to the microbiota, such as antibiotic administration, can alter microbial composition and result in the loss of colonization resistance. Consequently, the host may be rendered susceptible to colonization by a pathogen. This is a particularly relevant concern in the hospital setting...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Sohn Kim, April Covington, Eric G. Pamer Tags: INVITED REVIEW Source Type: research
Gut microbiota: Role in pathogen colonization, immune responses, and inflammatory disease
Summary
The intestinal tract of mammals is colonized by a large number of microorganisms including trillions of bacteria that are referred to collectively as the gut microbiota. These indigenous microorganisms have co‐evolved with the host in a symbiotic relationship. In addition to metabolic benefits, symbiotic bacteria provide the host with several functions that promote immune homeostasis, immune responses, and protection against pathogen colonization. The ability of symbiotic bacteria to inhibit pathogen colonization is mediated via several mechanisms including direct killing, competition for limited nutrients, and e...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Joseph M. Pickard, Melody Y. Zeng, Roberta Caruso, Gabriel N úñez Tags: INVITED REVIEW Source Type: research
Host ‐microbiota interactions and adaptive immunity
Summary
All mucosal surfaces are colonized with a vast number of microbes, which are essential for stimulating and regulating the immune system. While intrinsic and innate mechanisms exist to promote a strong barrier between the microbiota and the host to ensure compartmentalization, the microbiota is also able to induce robust adaptive immunity. In this review, we discuss the interplay between the microbiota and the adaptive immune system, with a focus on the induction of mucosal and systemic antibody responses and newly defined roles of maternal antibodies. We also highlight recent studies that aim to decipher microbial ...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Kathy D. McCoy, Francesca Ronchi, Markus B. Geuking Tags: INVITED REVIEW Source Type: research
Building conventions for unconventional lymphocytes
Summary
Falling between the classical characteristics of innate immune cells and adaptive T and B cells are a group of lymphocytes termed “unconventional.” These cells express antigen‐specific T or B cell receptors, but behave with innate characteristics. Well‐known members of this group include the gamma‐delta T cell and the Natural Killer T cell. Recent literature has greatly expanded scientific knowledge of unconventional lymphocytes, but key questions remain unresolved in the field, including why these cells have been maintained concurrently with conventional innate and adaptive immune cells. Here, we summari...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Lesley Pasman, Dennis L. Kasper Tags: INVITED REVIEW Source Type: research
Interplay of innate lymphoid cells and the microbiota
Summary
Innate lymphoid cells (ILC) are a recently identified group of innate lymphocytes that are preferentially located at barrier surfaces. Barrier surfaces are in direct contact with complex microbial ecosystems, collectively referred to as the microbiota. It is now believed that the interplay of the microbiota with host components (i.e. epithelial cells and immune cells) promotes host fitness by regulating organ homeostasis, metabolism, and host defense against pathogens. In this review, we will give an overview of this multifaceted interplay between ILC and components of the microbiota. (Source: Immunological Reviews)
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Liudmila Britanova, Andreas Diefenbach Tags: INVITED REVIEW Source Type: research
Interactions between bile salts, gut microbiota, and hepatic innate immunity
Summary
Bile salts are the water‐soluble end products of hepatic cholesterol catabolism that are released into the duodenum and solubilize lipids due to their amphipathic structure. Bile salts also act as endogenous ligands for dedicated nuclear receptors that exert a plethora of biological processes, mostly related to metabolism. Bile salts are actively reclaimed in the distal part of the small intestine, released into the portal system, and subsequently extracted by the liver. This enterohepatic cycle is critically dependent on dedicated bile salt transporters. In the intestinal lumen, bile salts exert direct antimicro...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Kristin Schubert, Steven W.M. Olde Damink, Martin Bergen, Frank G. Schaap Tags: INVITED REVIEW Source Type: research
Deciphering interactions between the gut microbiota and the immune system via microbial cultivation and minimal microbiomes
Summary
The community of microorganisms in the mammalian gastrointestinal tract, referred to as the gut microbiota, influences host physiology and immunity. The last decade of microbiome research has provided significant advancements for the field and highlighted the importance of gut microbes to states of both health and disease. Novel molecular techniques have unraveled the tremendous diversity of intestinal symbionts that potentially influence the host, many proof‐of‐concept studies have demonstrated causative roles of gut microbial communities in various pathologies, and microbiome‐based approaches are beginning ...
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Thomas Clavel, Jo ão Carlos Gomes‐Neto, Ilias Lagkouvardos, Amanda E. Ramer‐Tait Tags: INVITED REVIEW Source Type: research
Correlation, consequence, and functionality in microbiome ‐immune interplay
(Source: Immunological Reviews)
Source: Immunological Reviews - August 30, 2017 Category: Allergy & Immunology Authors: Oliver Pabst Tags: INTRODUCTION Source Type: research
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(Source: Immunological Reviews)
Source: Immunological Reviews - June 29, 2017 Category: Allergy & Immunology Tags: ISSUE INFORMATION Source Type: research
