Effects of Bacterial Metabolites on the Immune System: Enemies and Friends

2021 ◽  
Vol 21 ◽  
Author(s):  
Zaaima Al-Jabri ◽  
Iman Al-Reesi ◽  
Nawal Al-Shizawi ◽  
Mohammed S. Al-Balushi ◽  
Ali A. Al-Jabri ◽  
...  
Keyword(s):  
Immune System ◽  
Immune Responses ◽  
Pathogenic Bacteria ◽  
Bacterial Metabolites

: Metabolites produced by bacteria can influence the immune system. These metabolites are produced by pathogenic bacteria as well as the friendly microbiota. This review sheds light on the major bacterial metabolites and their structures. It also describes the capacity of these molecules to stimulate and inhibit the immune responses in a way that affects their capacity to control different diseases.

Immunomodulatory Effect of “Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy” to Cure or Prevent Hospital Acquired (Nosocomial) Infections due to Clostridium difficile (C. diff), other Pathogenic Bacteria, and Autoimmune Diseases

2018 ◽  
Vol 11 (1) ◽  
pp. 3937-3949
Author(s):  
Malireddy S Reddy
Keyword(s):  
Immune System ◽  
Gastrointestinal Tract ◽  
Pathogenic Bacteria ◽  
Molecular Level ◽  
Host Immune System ◽  
Hospital Acquired Infections ◽  
The World ◽  
Probiotic Strains ◽  
The Individual ◽  
Hospital Acquired

The worldwide popularity of Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy to treat or prevent the hospital acquired infections (nosocomial infections) arose a great interest in the medical community around the world (Reddy and Reddy, 2016; 2017). The following questions were raised on this subject: Does Multiple Mixed Strain Probiotics directly inhibit the pathogenic bacteria (C. diff) in the gastrointestinal tract or indirectly through modulation of the host immune system or both? To be more specific, what is the exact and/or hypothetical mechanism at molecular level behind the breakthrough discovery of Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy?  To answer these questions, the specific immunomodulation regulatory functions of the individual Probiotic strains (on host) have beenresearched, investigated andoutlined in this article.  A detailed explanation(s) and hypotheses have been proposed outlining the possible cumulativedirect bacteriological and indirect immunomodulatory effects (at the molecular level) of the Multiple Mixed Strain Probiotics used in Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy to successfully treat C. diff infection.  A detailed scientific and research attempts were made to correlate the Probiotic induced immune activities in relation to the reduction of the symptoms associated with the hospital acquired Clostridium difficile infection during and after the Multiple Mixed Strain Probioitc Therapy.  Results of the clinical trials, microbiological tests on feces, and the clinical blood tests significantly revealed that the reasons for the success of Dr. Reddy’s Multiple Mixed Strain Probiotic Therapy are multifold. Presumably, it is predominantly due to the immunomodulatory effect they have exerted on the host immune system along with the direct inhibition of C. diff bacteria by multiple Probiotics, due to the production of bacteriocins, lactic acid and nutritional competency.In addition, the size of the individual cells of the Probiotic strains in the Multiple Mixed Strain Probiotics and their significant effect on immunomodulation has been thoroughly discussed. Results clearly proved that if Probiotics are absent in the GI tract during C. diff infection, the chances of patient survival is zero.  This is because of the excess immune stimulation and incurable damage to the epithelial cell barrier of the gastrointestinal tract caused by C. diff bacteria.  The results also revealed, without any doubt, as of to-datethe latest discovery of Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy is the best way to cure the deadly hospital acquired infections affecting millions of people around the world, with high degree of mortality.  This has been attested by several practicng medical professionals and scientists around the world (Reddy and Reddy, 2017).

scholarly journals The immune response of T cells and therapeutic targets related to regulating the levels of T helper cells after ischaemic stroke

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Tian-Yu Lei ◽  
Ying-Ze Ye ◽  
Xi-Qun Zhu ◽  
Daniel Smerin ◽  
Li-Juan Gu ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Immune System ◽  
Immune Responses ◽  
Ischaemic Stroke ◽  
Immune Cells ◽  
Tissue Injury ◽  
Recovery Period ◽  
Vital Functions ◽  
Anti Inflammatory

AbstractThrough considerable effort in research and clinical studies, the immune system has been identified as a participant in the onset and progression of brain injury after ischaemic stroke. Due to the involvement of all types of immune cells, the roles of the immune system in stroke pathology and associated effects are complicated. Past research concentrated on the functions of monocytes and neutrophils in the pathogenesis of ischaemic stroke and tried to demonstrate the mechanisms of tissue injury and protection involving these immune cells. Within the past several years, an increasing number of studies have elucidated the vital functions of T cells in the innate and adaptive immune responses in both the acute and chronic phases of ischaemic stroke. Recently, the phenotypes of T cells with proinflammatory or anti-inflammatory function have been demonstrated in detail. T cells with distinctive phenotypes can also influence cerebral inflammation through various pathways, such as regulating the immune response, interacting with brain-resident immune cells and modulating neurogenesis and angiogenesis during different phases following stroke. In view of the limited treatment options available following stroke other than tissue plasminogen activator therapy, understanding the function of immune responses, especially T cell responses, in the post-stroke recovery period can provide a new therapeutic direction. Here, we discuss the different functions and temporal evolution of T cells with different phenotypes during the acute and chronic phases of ischaemic stroke. We suggest that modulating the balance between the proinflammatory and anti-inflammatory functions of T cells with distinct phenotypes may become a potential therapeutic approach that reduces the mortality and improves the functional outcomes and prognosis of patients suffering from ischaemic stroke.

Mathematical Interpretation of the Pharmacodynamics of Homoeopathic Medicines

2021 ◽  
Vol 34 (01) ◽  
pp. 003-016
Author(s):  
John Michel Warner
Keyword(s):  
Immune System ◽  
Immune Responses ◽  
Dose Response ◽  
Oral Route ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Force Line ◽  
Administration Routes ◽  
Medicinal Substances ◽  
Medicine Administration

AbstractAccording to Hahnemann, homoeopathic medicines must be great immune responses inducers. In crude states, these medicines pose severe threats to the immune system. So, the immune-system of an organism backfires against the molecules of the medicinal substances. The complex immune response mechanism activated by the medicinal molecules can handle any threats which are similar to the threats posed by the medicinal molecules. The intersectional operation of the two sets, medicine-induced immune responses and immune responses necessary to cure diseases, shows that any effective homoeopathic medicine, which is effective against any disease, can induce immune responses which are necessary to cure the specific disease. In this article, this mechanism has been exemplified by the action of Silicea in human body. Also, a neuroimmunological assessment of the route of medicine administration shows that the oral cavity and the nasal cavity are two administration-routes where the smallest doses (sometimes even few molecules) of a particular homoeopathic medicine induce the most effective and sufficient (in amount) purgatory immune responses. Administering the smallest unitary doses of Silicea in the oral route can make significant changes in the vital force line on the dose–response relationship graph. The dose–response relationship graph further implicates that the most effective dose of a medicine must be below the lethality threshold. If multiple doses of any medicine are administered at same intervals, the immune-system primarily engages with the medicinal molecules; but along the passage of time, the engagement line splits into two: one engages with the medicinal molecules and another engages with diseases. The immune system's engagement with the diseases increases along the passage of time, though the engagement with the medicinal molecules gradually falls with the administration of descending doses. Necessarily, I have shown through mathematical logic that the descending doses, though they seem to be funny, can effectively induce the most effective immune responses.

scholarly journals Gastric Microenvironment—A Partnership between Innate Immunity and Gastric Microbiota Tricks Helicobacter pylori

2021 ◽  
Vol 10 (15) ◽  
pp. 3258
Author(s):  
Cristina Oana Mărginean ◽  
Lorena Elena Meliț ◽  
Maria Oana Săsăran
Keyword(s):  
Helicobacter Pylori ◽  
Immune System ◽  
Pathogenic Bacteria ◽  
T Regulatory Cells ◽  
Inflammatory Responses ◽  
Mucosal Barrier ◽  
Pathogen Recognition ◽  
Microenvironmental Factors ◽  
H Pylori ◽  
Major Factors

Helicobacter pylori (H. pylori) carcinogenicity depends on three major factors: bacterial virulence constituents, environmental factors and host’s genetic susceptibility. The relationship between microenvironmental factors and H. pylori virulence factors are incontestable. H. pylori infection has a major impact on both gastric and colonic microbiota. The presence of non-H. pylori bacteria within the gastric ecosystem is particularly important since they might persistently act as an antigenic stimulus or establish a partnership with H. pylori in order to augment the subsequent inflammatory responses. The gastric ecosystem, i.e., microbiota composition in children with H. pylori infection is dominated by Streptoccocus, Neisseria, Rothia and Staphylococcus. The impairment of this ecosystem enhances growth and invasion of different pathogenic bacteria, further impairing the balance between the immune system and mucosal barrier. Moreover, altered microbiota due to H. pylori infection is involved in increasing the gastric T regulatory cells response in children. Since gastric homeostasis is defined by the partnership between commensal bacteria and host’s immune system, this review is focused on how pathogen recognition through toll-like receptors (TLRs—an essential class of pathogen recognition receptors—PRRs) on the surface of macrophages and dendritic cells impact the immune response in the setting of H. pylori infection. Further studies are required for delineate precise role of bacterial community features and of immune system components.

scholarly journals BAK1 Is Not a Target of the Pseudomonas syringae Effector AvrPto

2011 ◽  
Vol 24 (1) ◽  
pp. 100-107 ◽  
Author(s):  
Tingting Xiang ◽  
Na Zong ◽  
Jie Zhang ◽  
Jinfeng Chen ◽  
Mingsheng Chen ◽  
...  
Keyword(s):  
Cell Surface ◽  
Immune Responses ◽  
Pseudomonas Syringae ◽  
Plant Cell ◽  
Crucial Role ◽  
Pathogenic Bacteria ◽  
Effector Proteins ◽  
Receptor Like Kinase ◽  
Receptor Kinases ◽  
New Evidence

Plant cell surface-localized receptor kinases such as FLS2, EFR, and CERK1 play a crucial role in detecting invading pathogenic bacteria. Upon stimulation by bacterium-derived ligands, FLS2 and EFR interact with BAK1, a receptor-like kinase, to activate immune responses. A number of Pseudomonas syringae effector proteins are known to block immune responses mediated by these receptors. Previous reports suggested that both FLS2 and BAK1 could be targeted by the P. syringae effector AvrPto to inhibit plant defenses. Here, we provide new evidence further supporting that FLS2 but not BAK1 is targeted by AvrPto in plants. The AvrPto-FLS2 interaction prevented the phosphorylation of BIK1, a downstream component of the FLS2 pathway.

Probiotic alternatives to reduce gastrointestinal infections: the poultry experience

2005 ◽  
Vol 6 (1) ◽  
pp. 105-118 ◽  
Author(s):  
G. M. Nava ◽  
L. R. Bielke ◽  
T. R. Callaway ◽  
M. P Castañeda
Keyword(s):  
Immune Responses ◽  
Bacterial Communities ◽  
Pathogenic Bacteria ◽  
Therapeutic Interventions ◽  
Intestinal Lumen ◽  
Gastrointestinal Infections ◽  
Active Defense ◽  
Food Antigens ◽  
Host Health

AbstractThe intestinal mucosa represents the most active defense barrier against the continuous challenge of food antigens and pathogenic microorganisms present in the intestinal lumen. Protection against harmful agents is conferred by factors such as gastric acid, peristalsis, mucus, intestinal proteolysis, and the intestinal biota. The establishment of beneficial bacterial communities and metabolites from these complex ecosystems has varying consequences for host health. This hypothesis has led to the introduction of novel therapeutic interventions based on the consumption of beneficial bacterial cultures. Mechanisms by which probiotic bacteria affect the microecology of the gastrointestinal tract are not well understood, but at least three mechanisms of action have been proposed: production/presence of antibacterial substances (e.g., bacteriocins or colicins), modulation of immune responses and specific competition for adhesion receptors to intestinal epithelium. The rapid establishment of bacterial communities has been thought to be essential for the prevention of colonization by pathogenic bacteria. Some animal models suggest that the reduction in bacterial translocation in neonatal animals could be associated with an increase in intestinal bacterial communities and bacteriocin-like inhibitory substances produced by these species. This review emphasizes the role of the intestinal microbiota in the reduction of the gastrointestinal infections and draws heavily on studies in poultry.

scholarly journals Design and Encapsulation of Immunomodulators onto Gold Nanoparticles in Cancer Immunotherapy

2021 ◽  
Vol 22 (15) ◽  
pp. 8037
Author(s):  
Akshita Chauhan ◽  
Tabassum Khan ◽  
Abdelwahab Omri
Keyword(s):  
Immune System ◽  
Immune Responses ◽  
Cancer Immunotherapy ◽  
Cytotoxic T Lymphocytes ◽  
Recent Progress ◽  
Checkpoint Inhibitors ◽  
Drug Clearance ◽  
Cell Permeability ◽  
Plasmonic Effect ◽  
Cancer Immunotherapeutic

The aim of cancer immunotherapy is to reactivate autoimmune responses to combat cancer cells. To stimulate the immune system, immunomodulators, such as adjuvants, cytokines, vaccines, and checkpoint inhibitors, are extensively designed and studied. Immunomodulators have several drawbacks, such as drug instability, limited half-life, rapid drug clearance, and uncontrolled immune responses when used directly in cancer immunotherapy. Several strategies have been used to overcome these limitations. A simple and effective approach is the loading of immunomodulators onto gold-based nanoparticles (GNPs). As gold is highly biocompatible, GNPs can be administered intravenously, which aids in increasing cancer cell permeability and retention time. Various gold nanoplatforms, including nanospheres, nanoshells, nanorods, nanocages, and nanostars have been effectively used in cancer immunotherapy. Gold nanostars (GNS) are one of the most promising GNP platforms because of their unusual star-shaped geometry, which significantly increases light absorption and provides high photon-to-heat conversion efficiency due to the plasmonic effect. As a result, GNPs are a useful vehicle for delivering antigens and adjuvants that support the immune system in killing tumor cells by facilitating or activating cytotoxic T lymphocytes. This review represents recent progress in encapsulating immunomodulators into GNPs for utility in a cancer immunotherapeutic regimen.

Osteomyelitis

1995 ◽  
Vol 16 (10) ◽  
pp. 380-384
Author(s):  
Dennis R. Roy
Keyword(s):  
Immune System ◽  
Growth Plate ◽  
Pathogenic Bacteria ◽  
Chicken Pox ◽  
Hematogenous Osteomyelitis ◽  
Acute Hematogenous Osteomyelitis ◽  
Intercurrent Illness ◽  
Direct Inoculation ◽  
Focus Of Infection ◽  
Childhood Infection

Osteomyelitis, defined as an inflammation of bone generally caused by a pyogenic organism, is a common disorder of childhood. Infection most commonly is caused by blood-borne bacteria that localize in the metaphysis. Trauma or surgery also may result in direct inoculation or implantation of bacteria into the bone, or an adjacent focus of infection might extend directly to the bone, resulting in osteomyelitis. The etiology of acute hematogenous osteomyelitis is not understood completely. Bacteremia in childhood occurs frequently, if not daily; thus, the presence of bacteria alone may not explain why infection begins. Recent trauma coincidental with a bacteremia has been postulated. The presence of an intercurrent illness (ie, chicken pox) or infection may introduce a larger number of organisms or different pathogenic bacteria into the system or alter the immune system, making the host more susceptible. An understanding of the anatomy of bone and the pathogenesis of osteomyelitis is essential to appreciate the protean manifestations of the disorder. Pathogenesis In acute hematogenous osteomyelitis, infection is localized in the metapahysis. The circulation of the bone predisposes this region to the infection. Epiphyseal and metaphyseaal blood supplies generally are separate. The blood supply to the metaaphysis originagtes when the nutrient arteries send small terminala branches that end at the growth plate.

Cell-Penetrating Peptide-Mediated Nanovaccine Delivery

2021 ◽  
Vol 22 ◽  
Author(s):  
Jizong Jiang
Keyword(s):  
Immune System ◽  
Immune Responses ◽  
Cell Penetrating Peptide ◽  
Antigen Delivery ◽  
Efficient Manner ◽  
Antigen Uptake ◽  
Cell Penetrating ◽  
The Stability ◽  
Antigen Presenting

Abstract: Vaccination with small antigens, such as proteins, peptides, or nucleic acids, is used to activate the immune system and trigger the protective immune responses against a pathogen. Currently, nanovaccines are undergoing development instead of conventional vaccines. The size of nanovaccines is in the range of 10–500 nm, which enables them to be readily taken up by cells and exhibit improved safety profiles. However, low-level immune responses, as the removal of redundant pathogens, trigger counter-effective activation of the immune system invalidly and present a challenging obstacle to antigen recognition and its uptake via antigen-presenting cells (APCs). In addition, toxicity can be substantial. To overcome these problems, a variety of cell-penetrating peptide (CPP)-mediated vaccine delivery systems based on nanotechnology have been proposed, most of which are designed to improve the stability of antigens in vivo and their delivery into immune cells. CPPs are particularly attractive components of antigen delivery. Thus, the unique translocation property of CPPs ensures that they remain an attractive carrier with the capacity to deliver cargo in an efficient manner for the application of drugs, gene transfer, protein, and DNA/RNA vaccination delivery. CPP-mediated nanovaccines can enhance antigen uptake, processing, and presentation by APCs, which are the fundamental steps in initiating an immune response. This review describes the different types of CPP-based nanovaccines delivery strategies.

scholarly journals Phospholipase A2Inhibitors Synthesized by Two Entomopathogenic Bacteria, Xenorhabdus nematophila and Photorhabdus temperata subsp. temperata

2012 ◽  
Vol 78 (11) ◽  
pp. 3816-3823 ◽  
Author(s):  
Samyeol Seo ◽  
Sunghong Lee ◽  
Yongpyo Hong ◽  
Yonggyun Kim
Keyword(s):  
Immune Responses ◽  
Diamondback Moth ◽  
Culture Broth ◽  
Xenorhabdus Nematophila ◽  
Phenoloxidase Activity ◽  
Bacterial Metabolites ◽  
Content Type ◽  
Entomopathogenic Bacteria ◽  
Inhibitory Activities ◽  
Photorhabdus Temperata

ABSTRACTThe entomopathogenic bacteriaXenorhabdus nematophilaandPhotorhabdus temperatasubsp.temperatasuppress insect immune responses by inhibiting the catalytic activity of phospholipase A2(PLA2), which results in preventing biosynthesis of immune-mediating eicosanoids. This study identified PLA2inhibitors derived from culture broths of these two bacteria. BothX. nematophilaandP. temperatasubsp.temperataculture broths possessed significant PLA2-inhibitory activities. Fractionation of these bacterial metabolites in the culture broths using organic solvent and subsequent chromatography purified seven potent PLA2inhibitors, three of which (benzylideneacetone [BZA], proline-tyrosine [PY], and acetylated phenylalanine-glycine-valine [FGV]) were reported in a previous study. Four other compounds (indole, oxindole,cis-cyclo-PY, andp-hydroxyphenyl propionic acid) were identified and shown to significantly inhibit PLA2.X. nematophilaculture broth contained these seven compounds, whileP. temperatasubsp.temperataculture broth contained three compounds (BZA, acetylated FGV, andcis-cyclo-PY). BZA was detected in the largest amount among these PLA2compounds in both bacterial culture broths. All seven bacterial metabolites also showed significant inhibitory activities against immune responses, such as phenoloxidase activity and hemocytic nodulation; BZA was the most potent. Finally, this study characterized these seven compounds for their insecticidal activities against the diamondback moth,Plutella xylostella. Even though these compounds showed relatively low toxicities to larvae, they significantly enhanced the pathogenicity ofBacillus thuringiensis. This study reports bacterial-origin PLA2inhibitors, which would be applicable for developing novel insecticides.

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