Host poly(ADP-ribose) polymerases (PARPs) in acute and chronic bacterial infections

Protein ADP-ribosylation is a reversible post-translational modification, which alters protein activity, localization, interactome or stability, leading to perturbation of cell signaling. This review summarizes the emerging data indicating that host cell ADP-ribosylating enzymes, poly(ADP-ribose) polymerases (PARPs), influence the course of a bacterial infection, in parallel to ADP-ribosylating bacterial toxins. Host cell PARP targeting could be an efficient therapeutic approach to treat certain bacterial infections, possibly by repurposing the approved or clinical trial PARP inhibitors developed for cancer therapy.     

Understanding the role of SOCS signaling in neurodegenerative diseases: Current and emerging concepts

Suppressor of cytokine signaling proteins (SOCS) are a family of intracellular cytokine inducible proteins, consisting of eight members. They are involved in the complex control of the inflammatory response through their actions on various signaling pathways, including the JAK/STAT and NF-κB pathways. A series of studies has shown that SOCS proteins are involved in the regulation and progression of immune responses in microglia cells. The accumulated data suggest that modulation of SOCS expression could be a target for drug development aimed at controlling inflammation in the brain. This review focuses on the current understanding of SOCS proteins involvement in inflammation-based neurodegenerative diseases and their role as therapeutic targets in future approaches.     

MicroRNAs as mediators of insect host–pathogen interactions and immunity

Insects are the most successful group of animals on earth, owing this partly to their very effective immune responses to microbial invasion. These responses mainly include cellular and humoral responses as well as RNA interference (RNAi). Small non-coding RNAs (snRNAs) produced through RNAi are important molecules in the regulation of gene expression in almost all living organisms; contributing to important processes such as development, differentiation, immunity as well as host–microorganism interactions. The main snRNAs produced by the RNAi response include short interfering RNAs, microRNAs and piwi-interacting RNAs. In addition to the host snRNAs, some microorganisms encode snRNAs that affect the dynamics of host–pathogen interactions. In this review, we will discuss the latest developments in regards to the role of microRNA in insect host–pathogen interactions and provide some insights into this rapidly developing area of research.     

Microorganisms in the healthy upper reproductive tract: from denial to beneficial assignments for reproductive biology

Contrary to the traditional assumption of a sterile uterus, the number of studies characterizing microbial entities in the healthy upper reproductive tract (endometrial cavity, including follicular fluid and placenta) have been on the increase. Substantial data has been accumulated correlating microbial composition with fertility outcome. In this context, the presence of certain taxa was associated to an improved reproductive success. A summarization for the evidence of these molecular mechanisms through which bacteria may affect developmental processes during pregnancy is presented and discussed with special focus placed upon the immunological aspects.     

Impairment of the immune system in GH-overexpressing transgenic zebrafish (Danio rerio)

Growth hormone (GH) is an important regulator of immune functions in vertebrates, and it has been intensively reported a series of stimulatory actions of this hormone over on the immune system. Within aquaculture, overexpression of GH has been considered a promising alternative for promoting higher growth rates in organisms of commercial interest. Considering the various pleiotropic effects of GH, there are still few studies that aim to understand the consequences of the excess of GH on the physiological systems. In this context, our goal was to present the effects of the overexpression of GH on immune parameters using a model of zebrafish (Danio rerio) that overexpress this hormone. The results showed that GH transgenic zebrafish had 100% of mortality when immunosuppressed with dexamethasone, revealing a prior weakening of the immune system in this lineage. Morphometric analysis of thymus and head kidney revealed a reduction in the area of these structures in transgenic zebrafish. Moreover, the phenotypic expression of CD3 and CD4 thymocytes was also depreciated in transgenic zebrafish. Furthermore, a decrease was noted in the expression of genes RAG-1 (60%), IKAROS (50%), IL-1β (55%), CD4 (60%) and CD247 (40%), indicating that development parameters, of innate and acquired immunity, are being harmed. Based on these results, it can be concluded that the excess of GH impairs the immune functions in GH transgenic zebrafish, indicating that the maintenance of normal levels of this hormone is essential for the functioning of immunological activities.     

Ablastin: The phenomenon

A brief report is made of a conference held on the subject of ablastic immunity. Included are the background of the meeting, its organization, and its purpose, which was to summarize our knowledge of the subject and to consider future research plans. A list of some of the research problems discussed by the participants and possible experimental approaches for their resolution are presented. The report also serves as an introduction to a series of papers by the participants of the conference published concurrently.     

Immunologic aspects of human colostrum and milk—A misinterpretation

Interpretations of the demographic impact of Western diseases are frequently clouded by a failure to appreciate the complex nature of immune responses. It is commonly assumed that epidemic diseases are generally characterized by both transplacental and lacteal transmission of maternal antibodies. This is not, however, the case for viral diseases, such as measles, smallpox, and influenza–-all of which reached epidemic proportions during the post-Columbian era. In this paper I review the nature of the immune response for viral diseases, with emphasis upon measles, a disease that contributed heavily to the demise of native peoples. © 1994 Wiley-Liss, Inc.