Rev Med Inst Mex Seguro Soc
September 2024
With the increase in the number of people with advanced age (> 60 years) worldwide, it is necessary to understand the processes that lead to healthy aging. Cellular senescence, immunosenescence and inflammaging are part of the natural process of aging and are associated with age-related diseases. Cellular senescence is characterized by the arrest of the cell cycle in the G1 phase.
View Article and Find Full Text PDFHumans are exposed every day to innumerable external stimuli, both environmental and microbial. Immunological memory recalls each specific stimulus and mounts a secondary response that is faster and of a larger magnitude than the primary response; this process constitutes the basis for vaccine development. The COVID-19 pandemic offers a unique opportunity to study the development of immune memory against an emergent microorganism.
View Article and Find Full Text PDFPathogenic bacteria have several mechanisms to evade the host's immune response and achieve an efficient infection. Bacterial extracellular vesicles (EVs) are a relevant cellular communication mechanism, since they can interact with other bacterial cells and with host cells. In this review, we focus on the EVs produced by some World Health Organization (WHO) priority Gram-negative and Gram-positive pathogenic bacteria; by spore-producing bacteria; by (a bacteria with a complex cell wall); and by (a bacteria without lipopolysaccharide).
View Article and Find Full Text PDFBackground: Upper respiratory tract infections (URIs) are very common in the pediatric population. Most of these infections are mild, but due to their chronicity they affect quality of life (QoL), in addition to high costs for medical care. The use of bacterial extracts (BE) that stimulate general immunity can reduce its frequency and improve the QoL of the patient.
View Article and Find Full Text PDFJ Leukoc Biol
June 2023
Tuberculosis remains one of the leading public health problems in the world. The mechanisms that lead to the activation of the immune response against Mycobacterium tuberculosis have been extensively studied, with a focus on the role of cytokines as the main signals for immune cell communication. However, less is known about the role of other signals, such as extracellular vesicles, in the communication between immune cells, particularly during the activation of the adaptive immune response.
View Article and Find Full Text PDFChagas disease is caused by and represents a major public health problem, which is endemic in Latin America and emerging in the rest of the world. The two drugs that are currently available for its treatment, Benznidazole and Nifurtimox, are partially effective in the chronic phase of the disease. In this study, we designed and synthesized the benzyl ester of N-isopropyl oxamic acid (B-NIPOx), which is a non-polar molecule that crosses cell membranes.
View Article and Find Full Text PDFThe clinical presentation of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), ranges between mild respiratory symptoms and a severe disease that shares many of the features of sepsis. Sepsis is a deregulated response to infection that causes life-threatening organ failure. During sepsis, the intestinal epithelial cells are affected, causing an increase in intestinal permeability and allowing microbial translocation from the intestine to the circulation, which exacerbates the inflammatory response.
View Article and Find Full Text PDFMembranes (Basel)
June 2022
Liposomes are artificial models of cellular membranes that are used as delivery systems for genes, drugs and protein antigens. We have previously used them to study the antigenic properties of their phospholipids. Here, we used them to induce the production of IgG anti-non-bilayer phospholipid arrangements (NPAs) antibodies in mice; these antibodies cause cell lysis and trigger a lupus-like disease in mice.
View Article and Find Full Text PDFMicrobiol Immunol
October 2022
Most individuals infected with Mycobacterium tuberculosis (Mtb) have latent tuberculosis (TB), which can be diagnosed with tests (such as the QuantiFERON-TB Gold test [QFT]) that detect the production of IFN-γ by memory T cells in response to the Mtb-specific antigens 6 kDa early secretory antigenic target EsxA (Rv3875) (ESAT-6), 10 kDa culture filtrate antigen EsxB (Rv3874) (CFP-10), and Mtb antigen of 7.7 kDa (Rv2654c) (TB7.7).
View Article and Find Full Text PDFAcute systemic inflammation can lead to life-threatening organ dysfunction. In patients with sepsis, systemic inflammation is triggered in response to infection, but in other patients, a systemic inflammatory response syndrome (SIRS) is triggered by non-infectious events. IL-6 is a major mediator of inflammation, including systemic inflammatory responses.
View Article and Find Full Text PDFNon-bilayer phospholipids arrangements (NPAs) are transient molecular associations different from lipid bilayers. When they become stable, they can trigger a disease in mice resembling human lupus, which is mainly characterized by the production of anti-NPA IgG antibodies. NPAs are stabilized on liposomes or cell bilayers by the drugs procainamide or chlorpromazine, which produce drug-induced lupus in humans.
View Article and Find Full Text PDFValproic acid (VPA) is a drug commonly used for epileptic seizure control. Recently, it has been shown that VPA alters the activation of several immune cells, including Natural Killer (NK) cells, which play an important role in the containment of viruses and intracellular bacteria. Although VPA can increase susceptibility to extracellular pathogens, it is unknown whether the suppressor effect of VPA could affect the course of intracellular bacterial infection.
View Article and Find Full Text PDFMast cell activation through the high-affinity IgE receptor (FcεRI) plays a central role in allergic reactions. FcεRI-mediated activation triggers multiple signaling pathways leading to degranulation and synthesis of different inflammatory mediators. IgE-mediated mast cell activation can be modulated by different molecules, including several drugs.
View Article and Find Full Text PDFinfections remain a challenging health issue, causing significant morbidity and mortality worldwide. Current vaccines against typhoid fever display moderate efficacy whilst no licensed vaccines are available for paratyphoid fever or invasive non-typhoidal salmonellosis. Therefore, there is an urgent need to develop high efficacy broad-spectrum vaccines that can protect against typhoidal and non-typhoidal .
View Article and Find Full Text PDFInt J Nanomedicine
February 2020
Background: Tuberculosis is the leading cause of death by an infectious microorganism worldwide. Conventional treatment lasts at least six months and has adverse effects; therefore, it is important to find therapeutic alternatives that reduce the bacterial load and may reduce the treatment duration. The immune response against tuberculosis can be modulated by several mechanisms, including extracellular vesicles (EVs), which are nano-sized membrane-bound structures that constitute an efficient communication mechanism among immune cells.
View Article and Find Full Text PDFMol Immunol
July 2019
Salmonella enterica serovar Typhimurium (S. Typhimurium) changes the structure of its lipopolysaccharide (LPS) in response to the environment. The two main LPS variants found in S.
View Article and Find Full Text PDFArch Med Res
October 2018
Introduction: Cell damage in Acute Pancreatitis (AP) lead to release of cytokines and HMGB1 and Hsp70. While Hsp70 plays a role in cytoprotection, when released to extracellular milieu constitutes, as HMGB1, a danger signal and trigger pro-inflammatory responses. These molecules seem to be related to the clinical progression; but because no evidence exists about them as molecular network in AP development, we quantify HSP70, HMGB1, and cytokines in patients with AP and search for correlations with severity and prognosis.
View Article and Find Full Text PDFTuberculosis is one of the leading causes of mortality worldwide, it is caused by Mycobacterium tuberculosis (Mtb), a bacteria that employs several strategies to evade the host immune response. For instance, Mtb interferes with the overexpression of class II transactivator (CIITA) in macrophages exposed to IFN-γ by inhibiting histone acetylation at its promoter, which can be reverted by the histone deacetylase inhibitor (HDACi) sodium butyrate. In this work, we evaluated whether a different HDACi, valproic acid (VPA), could revert the inhibition of gene expression induced by Mtb.
View Article and Find Full Text PDFSepsis, one of the leading causes of death in intensive care units, is caused by a dysregulated host response to infection that leads to life-threatening organ dysfunction. The proinflammatory and anti-inflammatory responses activated by the infecting microorganism become systemic, and the sustained anti-inflammatory response induces a state of immunosuppression that is characterized by decreased expression of HLA-DR on monocytes, T cell apoptosis, and reduced production of TNF-α by monocytes and macrophages in response to TLR ligands. Innate lymphoid cells (ILCs) are lymphocytes that lack Ag-specific receptors and lineage-specific markers; they express HLA-DR and are activated by cytokines and by direct recognition of microbial molecules.
View Article and Find Full Text PDFFront Immunol
April 2019
Tuberculosis is an infectious disease caused by (Mtb). In the lungs, macrophages and neutrophils are the first immune cells that have contact with the infecting mycobacteria. Neutrophils are phagocytic cells that kill microorganisms through several mechanisms, which include the lytic enzymes and antimicrobial peptides that are found in their lysosomes, and the production of reactive oxygen species.
View Article and Find Full Text PDFInnate lymphoid cells (ILCs) are lymphocytes lacking antigen recognition receptors and become activated in response to cytokines and through microbe-associated molecular pattern (MAMP) receptors. ILCs are found mainly in mucosal tissues and participate in the immune response against infections and in chronic inflammatory conditions. ILCs are divided in ILC-1, ILC-2 and ILC-3, and these cells have analogue functions to those of immune adaptive response lymphocytes Th1, Th2 and Th17.
View Article and Find Full Text PDFBackground: The presence of digestive fistula involves chronic inflammation and fibrosis. It has been reported that ω3-polyunsaturated fatty acids stimulate the resolution of inflammation.
Aim: Determine if the administration of oral ω3 reduces fistula output and the time required for fistula closure.
Anti-lipid IgG antibodies are produced in some mycobacterial infections and in certain autoimmune diseases [such as anti-phospholipid syndrome, systemic lupus erythematosus (SLE)]. However, few studies have addressed the B cell responses underlying the production of these immunoglobulins. Anti-lipid IgG antibodies are consistently found in a murine model resembling human lupus induced by chlorpromazine-stabilized non-bilayer phospholipid arrangements (NPA).
View Article and Find Full Text PDFObjective: In the spondyloarthritides (SpA), increased numbers of CD4+ T cells express killer cell immunoglobulin-like receptor 3DL2 (KIR-3DL2). The aim of this study was to determine the factors that induce KIR-3DL2 expression, and to characterize the relationship between HLA-B27 and the phenotype and function of KIR-3DL2-expressing CD4+ T cells in SpA.
Methods: In total, 34 B27+ patients with SpA, 28 age- and sex-matched healthy controls (20 B27- and 8 B27+), and 9 patients with rheumatoid arthritis were studied.