Manganese homeostasis at the host-pathogen interface and in the host immune system

The intracellular parasite Toxoplasma gondii has long provided a tractable experimental system to investigate how the immune system deals with intracellular infections. This review highlights the advances in defining how this organism was first detected and the studies with T. gondii that contribute to our understanding of how the cytokine IFN-γ promotes control of vacuolar pathogens. In addition, the genetic tractability of this eukaryote organism has provided the foundation for studies into the diverse strategies that pathogens use to evade antimicrobial responses and now provides the opportunity to study the basis for latency. Thus, T. gondii remains a clinically relevant organism whose evolving interactions with the host immune system continue to teach lessons broadly relevant to host–pathogen interactions.

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An Evolutionary Arms Race Between Burkholderia pseudomallei and Host Immune System: What Do We Know?

Frontiers in Microbiology ◽

10.3389/fmicb.2020.612568 ◽

2021 ◽

Vol 11 ◽

Author(s):

Chalita Chomkatekaew ◽

Phumrapee Boonklang ◽

Apiwat Sangphukieo ◽

Claire Chewapreecha

Keyword(s):

Genetic Diversity ◽

Immune System ◽

Burkholderia Pseudomallei ◽

Host Population ◽

Ecological Niches ◽

Host Immune System ◽

Structural Variations ◽

Evolutionary Trajectory ◽

Human Host ◽

Host Pathogen

A better understanding of co-evolution between pathogens and hosts holds promise for better prevention and control strategies. This review will explore the interactions between Burkholderia pseudomallei, an environmental and opportunistic pathogen, and the human host immune system. B. pseudomallei causes “Melioidosis,” a rapidly fatal tropical infectious disease predicted to affect 165,000 cases annually worldwide, of which 89,000 are fatal. Genetic heterogeneities were reported in both B. pseudomallei and human host population, some of which may, at least in part, contribute to inter-individual differences in disease susceptibility. Here, we review (i) a multi-host—pathogen characteristic of the interaction; (ii) selection pressures acting on B. pseudomallei and human genomes with the former being driven by bacterial adaptation across ranges of ecological niches while the latter are driven by human encounter of broad ranges of pathogens; (iii) the mechanisms that generate genetic diversity in bacterial and host population particularly in sequences encoding proteins functioning in host—pathogen interaction; (iv) reported genetic and structural variations of proteins or molecules observed in B. pseudomallei—human host interactions and their implications in infection outcomes. Together, these predict bacterial and host evolutionary trajectory which continues to generate genetic diversity in bacterium and operates host immune selection at the molecular level.

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Cryptococcus neoformans Rim101 Is Associated with Cell Wall Remodeling and Evasion of the Host Immune Responses

mBio ◽

10.1128/mbio.00522-12 ◽

2013 ◽

Vol 4 (1) ◽

Cited By ~ 55

Author(s):

Teresa R. O'Meara ◽

Stephanie M. Holmer ◽

Kyla Selvig ◽

Fred Dietrich ◽

J. Andrew Alspaugh

Keyword(s):

Immune Response ◽

Cell Wall ◽

Transcription Factor ◽

Immune System ◽

Immune Responses ◽

Cryptococcus Neoformans ◽

Host Immune Response ◽

Host Immune System ◽

Content Type ◽

Host Pathogen

ABSTRACTInfectious microorganisms often play a role in modulating the immune responses of their infected hosts. We demonstrate thatCryptococcus neoformanssignals through the Rim101 transcription factor to regulate cell wall composition and the host-pathogen interface. In the absence of Rim101,C. neoformansexhibits an altered cell surface in response to host signals, generating an excessive and ineffective immune response that results in accelerated host death. This host immune response to therim101Δ mutant strain is characterized by increased neutrophil influx into the infected lungs and an altered pattern of host cytokine expression compared to the response to wild-type cryptococcal infection. To identify genes associated with the observed phenotypes, we performed whole-genome RNA sequencing experiments under capsule-inducing conditions. We defined the downstream regulon of the Rim101 transcription factor and determined potential cell wall processes involved in the capsule attachment defects and altered mechanisms of virulence in therim101Δ mutant. The cell wall generates structural stability for the cell and allows the attachment of surface molecules such as capsule polysaccharides. In turn, the capsule provides an effective mask for the immunogenic cell wall, shielding it from recognition by the host immune system.IMPORTANCECryptococcus neoformansis an opportunistic human pathogen that is a significant cause of death in immunocompromised individuals. There are two major causes of death due to this pathogen: meningitis due to uncontrolled fungal proliferation in the brain in the face of a weakened immune system and immune reconstitution inflammatory syndrome characterized by an overactive immune response to subclinical levels of the pathogen. In this study, we examined howC. neoformansuses the conserved Rim101 transcription factor to specifically remodel the host-pathogen interface, thus regulating the host immune response. These studies explored the complex ways in which successful microbial pathogens induce phenotypes that ensure their own survival while simultaneously controlling the nature and degree of the associated host response.

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Glycomaterials for probing host–pathogen interactions and the immune response

Experimental Biology and Medicine ◽

10.1177/1535370216647811 ◽

2016 ◽

Vol 241 (10) ◽

pp. 1042-1053 ◽

Cited By ~ 3

Author(s):

Mia L Huang ◽

Christopher J Fisher ◽

Kamil Godula

Keyword(s):

Immune Response ◽

Immune System ◽

Cell Surface ◽

Host Response ◽

Host Immune Response ◽

Host Cells ◽

Host Immune System ◽

Host Pathogen Interactions ◽

Host Pathogen ◽

Functional Complexity

The initial engagement of host cells by pathogens is often mediated by glycan structures presented on the cell surface. Various components of the glycocalyx can be targeted by pathogens for adhesion to facilitate infection. Glycans also play integral roles in the modulation of the host immune response to infection. Therefore, understanding the parameters that define glycan interactions with both pathogens and the various components of the host immune system can aid in the development of strategies to prevent, interrupt, or manage infection. Glycomaterials provide a unique and powerful tool with which to interrogate the compositional and functional complexity of the glycocalyx. The objective of this review is to highlight some key contributions from this area of research in deciphering the mechanisms of pathogenesis and the associated host response.

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When the Going Gets Rough: The Significance of Brucella Lipopolysaccharide Phenotype in Host–Pathogen Interactions

Frontiers in Microbiology ◽

10.3389/fmicb.2021.713157 ◽

2021 ◽

Vol 12 ◽

Author(s):

Lauren W. Stranahan ◽

Angela M. Arenas-Gamboa

Keyword(s):

Immune System ◽

Outer Membrane ◽

Vaccine Development ◽

Outer Membrane Proteins ◽

Host Cells ◽

Host Immune System ◽

Host Pathogen Interactions ◽

Zoonotic Infections ◽

Host Pathogen

Brucella is a facultatively intracellular bacterial pathogen and the cause of worldwide zoonotic infections, infamous for its ability to evade the immune system and persist chronically within host cells. Despite the frequent association with attenuation in other Gram-negative bacteria, a rough lipopolysaccharide phenotype is retained by Brucella canis and Brucella ovis, which remain fully virulent in their natural canine and ovine hosts, respectively. While these natural rough strains lack the O-polysaccharide they, like their smooth counterparts, are able to evade and manipulate the host immune system by exhibiting low endotoxic activity, resisting destruction by complement and antimicrobial peptides, entering and trafficking within host cells along a similar pathway, and interfering with MHC-II antigen presentation. B. canis and B. ovis appear to have compensated for their roughness by alterations to their outer membrane, especially in regards to outer membrane proteins. B. canis, in particular, also shows evidence of being less proinflammatory in vivo, suggesting that the rough phenotype may be associated with an enhanced level of stealth that could allow these pathogens to persist for longer periods of time undetected. Nevertheless, much additional work is required to understand the correlates of immune protection against the natural rough Brucella spp., a critical step toward development of much-needed vaccines. This review will highlight the significance of rough lipopolysaccharide in the context of both natural disease and host–pathogen interactions with an emphasis on natural rough Brucella spp. and the implications for vaccine development.

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Role of Vasavaleha in the management of Covid19

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v11ispl1.2710 ◽

2020 ◽

Vol 11 (SPL1) ◽

pp. 259-261

Author(s):

Aamir Khan ◽

Rajni K. Gurmule

Keyword(s):

Immune System ◽

Human Body ◽

Respiratory Diseases ◽

Spreading Rate ◽

Host Immune System ◽

Shortness Of Breath ◽

Antitussive Effect ◽

Corona Viruses ◽

Very High

Vasavaleha is one of the best medicine given for respiratory diseases. Corona viruses typically affect the respiratory system, causing symptoms such as coughing, fever and shortness of breath. It also affects host immune system of human body. Spreading rate of this disease is very high. Whole world is seeking for the treatment which can uproots this diseases. There in no vaccine available till date against this pandemic disease. Ayurveda mainly focuses on prevention of diseases alongwith its total cure. Rajyakshma Vyadhi is MadhyamMarga Roga as per Ayurveda. It shows many symptoms such as Kasa, Shwasa etc. By overall view of Covid 19, shows its resemblance with Rajyakshma Vyadhi described in Ayurveda. Vasavaleha is a Kalpa which is described in Rogadhikara of Rajyakshma. It shows Kasahara, Shwashara properties. It consists of Vasa, Pipalli, Madhu and Goghrita. These components shows actions like bronchodilation, antitussive effect and many more other actions. Pipalli shows important Rasayana effect. So in present review, we have tried to focus on role of Vasavaleha in the management of Covid 19. This can be used as preventive as well as adjuvant medication in treating Covid 19. There is need of further clinical research to rule of exact action of Vasavaleha against Covid 19.

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