scholarly journals Dual-Wavelength Photosensitive Nano-in-Micro Scaffold Regulates Innate and Adaptive Immune Responses for Osteogenesis

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Qin Zhao ◽  
Miusi Shi ◽  
Chengcheng Yin ◽  
Zifan Zhao ◽  
Jinglun Zhang ◽  
...  
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Immune Cells ◽  
Inflammatory Responses ◽  
Macrophage Polarization ◽  
T Cell Response ◽  
Dual Wavelength ◽  
M2 Macrophage ◽  
Adaptive Immune Responses ◽  
Adaptive Immune

AbstractThe immune response of a biomaterial determines its osteoinductive effect. Although the mechanisms by which some immune cells promote regeneration have been revealed, the biomaterial-induced immune response is a dynamic process involving multiple cells. Currently, it is challenging to accurately regulate the innate and adaptive immune responses to promote osteoinduction in biomaterials. Herein, we investigated the roles of macrophages and dendritic cells (DCs) during the osteoinduction of biphasic calcium phosphate (BCP) scaffolds. We found that osteoinductive BCP directed M2 macrophage polarization and inhibited DC maturation, resulting in low T cell response and efficient osteogenesis. Accordingly, a dual-targeting nano-in-micro scaffold (BCP loaded with gold nanocage, BCP-GNC) was designed to regulate the immune responses of macrophages and DCs. Through a dual-wavelength photosensitive switch, BCP-GNC releases interleukin-4 in the early stage of osteoinduction to target M2 macrophages and then releases dexamethasone in the later stage to target immature DCs, creating a desirable inflammatory environment for osteogenesis. This study demonstrates that biomaterials developed to have specific regulatory capacities for immune cells can be used to control the early inflammatory responses of implanted materials and induce osteogenesis.

scholarly journals Leptin’s and antigen-presenting cells’ functions in periodontitis – an overview / Leptin e as funções das células que apresentam antigénios na periodontite - uma visão geral

2021 ◽  
Vol 4 (2) ◽  
pp. 8011-8019
Author(s):  
Giovanna Ganem Favero ◽  
Isabela Lopes Martin ◽  
Fernanda Pereira da Silva Albino ◽  
Carlos Eduardo Fontana ◽  
Sérgio Luiz Pinheiro ◽  
...  
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Immune Responses ◽  
Inflammatory Responses ◽  
Antigen Presenting Cells ◽  
Adaptive Immune Responses ◽  
Adaptive Immune ◽  
Inflammatory Immune Response ◽  
Antigen Presenting ◽  
The Relationship

Leptin is a hormone synthesized predominantly by white adipose tissue. Its production levels are directly proportional to the total mass of this tissue in an individual’s body. Apart from its classic role in the regulation of hunger and satiety, it also plays an important part in scenarios involving innate and adaptive immune responses. It has been discovered that leptin levels are altered in a variety of inflammatory responses, such as periodontitis, a condition which derives from a persistent inflammatory immune response from a host facing bacterial infection. The initial trigger for this reaction is the recognition of the pathogens by antigen presenting cells, such as macrophages and dendritic cells, whose actions can be influenced by leptin. This review aims to present the relationship between leptin, dendritic cells and macrophages in the context of periodontal disease. Thus, we have assembled the most important findings related to leptin’s role in the modulation of the immune response carried out by these cells in periodontitis.

scholarly journals SARS-CoV-2 Serology Status Detected by Commercialized Platforms Distinguishes Previous Infection and Vaccination Adaptive Immune Responses

2021 ◽  
Author(s):  
Raymond T. Suhandynata ◽  
Nicholas J. Bevins ◽  
Jenny T. Tran ◽  
Deli Huang ◽  
Melissa A. Hoffman ◽  
...  
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Neutralizing Antibodies ◽  
Natural Infection ◽  
Adaptive Immune Response ◽  
Antibody Assay ◽  
Adaptive Immune Responses ◽  
Adaptive Immune ◽  
Previous Infection ◽  
A Cell

AbstractBackgroundThe severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected over 110 million individuals and led to 2.5 million deaths worldwide. As more individuals are vaccinated, the clinical performance and utility of SARS-CoV-2 serology platforms needs to be evaluated.MethodsThe ability of four commercial SARS-CoV-2 serology platforms to detect previous infection or vaccination were evaluated using a cohort of 53 SARS-CoV-2 PCR-positive patients, 89 SARS-CoV-2-vaccinated healthcare workers (Pfizer or Moderna), and 127 SARS-CoV-2 negative patients. Serology results were compared to a cell based SARS-CoV-2 pseudovirus (PSV) neutralizing antibodies assay.ResultsThe Roche S-(spike) antibody and Diazyme neutralizing antibodies (NAbs) assays detected adaptive immune response in 100.0% and 90.1% of vaccinated individuals who received two-doses of vaccine (initial and booster), respectively. The Roche N-(nucleocapsid) antibody assay and Diazyme IgG assay did not detect adaptive immune response in vaccinated individuals. The Diazyme Nabs assay correlated with the PSV SARS-CoV-2 ID50 neutralization titers (R2= 0.70), while correlation of the Roche S-antibody assay was weaker (R2= 0.39). Median PSV SARS-CoV-2 ID50 titers more than doubled in vaccinated individuals who received two-doses of the Moderna vaccine (ID50: 597) compared to individuals that received a single dose (ID50: 284).ConclusionsThe Roche S-antibody and Diazyme NAbs assays robustly detected adaptive immune responses in SARS-CoV-2 vaccinated individuals and SARS-CoV-2 infected individuals. The Diazyme NAbs assay strongly correlates with the PSV SARS-CoV-2 NAbs in vaccinated individuals. Understanding the reactivity of commercially available serology platforms is important when distinguishing vaccination response versus natural infection.SummaryThe Roche S (spike protein)-antibody and Diazyme neutralizing-antibodies (NAbs) assays were evaluated for their clinical utility in the detection of SARS-CoV-2 related adaptive immune responses by testing SARS-CoV-2 PCR-confirmed patients, SARS-CoV-2-vaccinated individuals, and SARS-CoV-2-negative individuals. Commercial serology results were compared to results generated using a cell-based SARS-CoV-2 pseudovirus (PSV) NAbs assay and previously validated SARS-CoV-2 commercial serology assays (Roche N (nucleocapsid protein) antibody and Diazyme IgG). We demonstrate that the Roche S-antibody and Diazyme NAbs assays detected adaptive immune response in SARS-CoV-2 vaccinated individuals and the presence of SARS-CoV-2 PSV NAbs. The Roche S-antibody assay had an observed positive percent agreement (PPA) of 100% for individuals who received two doses of the Pfizer or Moderna vaccine. By contrast, the Roche N assay and Diazyme IgG assay did not detect vaccine adaptive immune responses. Our findings also indicate that the Diazyme NAbs assay correlates strongly with the levels of SARS-CoV-2 ID50 neutralization titers using the PSV Nab assay in vaccinated individuals.

Adaptive immunity

2020 ◽  
pp. 325-336
Author(s):  
Paul Klenerman
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Adaptive Immunity ◽  
Innate Immune Response ◽  
Molecular Basis ◽  
Adaptive Immune Response ◽  
Antigenic Specificity ◽  
Adaptive Immune Responses ◽  
Research Attention ◽  
Adaptive Immune

The adaptive immune response is distinguished from the innate immune response by two main features: its capacity to respond flexibly to new, previously unencountered antigens (antigenic specificity), and its enhanced capacity to respond to previously encountered antigens (immunological memory). These two features have provided the focus for much research attention, from the time of Jenner, through Pasteur onwards. Historically, innate and adaptive immune responses have often been treated as separate, with the latter being considered more ‘advanced’ because of its flexibility. It is now clear this not the case, and in recent years the molecular basis for these phenomena has become much better understood.

scholarly journals Mutations in a Highly Conserved Motif of nsp1β Protein Attenuate the Innate Immune Suppression Function of Porcine Reproductive and Respiratory Syndrome Virus

2016 ◽  
Vol 90 (7) ◽  
pp. 3584-3599 ◽  
Author(s):  
Yanhua Li ◽  
Duan-Liang Shyu ◽  
Pengcheng Shang ◽  
Jianfa Bai ◽  
Kang Ouyang ◽  
...  
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Innate Immune ◽  
Respiratory Syndrome Virus ◽  
Adaptive Immune Responses ◽  
Virus Growth ◽  
Conserved Motif ◽  
Adaptive Immune ◽  
Infected Cells ◽  
Growth Ability

ABSTRACTPorcine reproductive and respiratory syndrome virus (PRRSV) nonstructural protein 1β (nsp1β) is a multifunctional viral protein, which is involved in suppressing the host innate immune response and activating a unique −2/−1 programmed ribosomal frameshifting (PRF) signal for the expression of frameshifting products. In this study, site-directed mutagenesis analysis showed that the R128A or R129A mutation introduced into a highly conserved motif (123GKYLQRRLQ131) reduced the ability of nsp1β to suppress interferon beta (IFN-β) activation and also impaired nsp1β's function as a PRF transactivator. Three recombinant viruses, vR128A, vR129A, and vRR129AA, carrying single or double mutations in the GKYLQRRLQ motif were characterized. In comparison to the wild-type (WT) virus, vR128A and vR129A showed slightly reduced growth abilities, while the vRR129AA mutant had a significantly reduced growth ability in infected cells. Consistent with the attenuated growth phenotypein vitro, pigs infected with nsp1β mutants had lower levels of viremia than did WT virus-infected pigs. Compared to the WT virus in infected cells, all three mutated viruses stimulated high levels of IFN-α expression and exhibited a reduced ability to suppress the mRNA expression of selected interferon-stimulated genes (ISGs). In pigs infected with nsp1β mutants, IFN-α production was increased in the lungs at early time points postinfection, which was correlated with increased innate NK cell function. Furthermore, the augmented innate response was consistent with the increased production of IFN-γ in pigs infected with mutated viruses. These data demonstrate that residues R128 and R129 are critical for nsp1β function and that modifying these key residues in the GKYLQRRLQ motif attenuates virus growth ability and improves the innate and adaptive immune responses in infected animals.IMPORTANCEPRRSV infection induces poor antiviral innate IFN and cytokine responses, which results in weak adaptive immunity. One of the strategies in next-generation vaccine construction is to manipulate viral proteins/genetic elements involved in antagonizing the host immune response. PRRSV nsp1β was identified to be a strong innate immune antagonist. In this study, two basic amino acids, R128 and R129, in a highly conserved GKYLQRRLQ motif were determined to be critical for nsp1β function. Mutations introduced into these two residues attenuated virus growth and improved the innate and adaptive immune responses of infected animals. Technologies developed in this study could be broadly applied to current commercial PRRSV modified live-virus (MLV) vaccines and other candidate vaccines.

scholarly journals The colonic macrophage transcription factor RBP-J orchestrates intestinal immunity against bacterial pathogens

2020 ◽  
Vol 217 (4) ◽  
Author(s):  
Lan Kang ◽  
Xiang Zhang ◽  
Liangliang Ji ◽  
Tiantian Kou ◽  
Sinead M. Smith ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Immune Responses ◽  
Inflammatory Responses ◽  
Late Phase ◽  
Intestinal Immunity ◽  
Adaptive Immune Responses ◽  
Cell Lineages ◽  
Adaptive Immune ◽  
Intestinal Macrophage ◽  
Pathogen Clearance

Macrophages play pleiotropic roles in maintaining the balance between immune tolerance and inflammatory responses in the gut. Here, we identified transcription factor RBP-J as a crucial regulator of colonic macrophage–mediated immune responses against the enteric pathogen Citrobacter rodentium. In the immune response phase, RBP-J promoted pathogen clearance by enhancing intestinal macrophage-elicited Th17 cell immune responses, which was achieved by maintenance of C/EBPβ-dependent IL-6 production by overcoming miRNA-17∼92–mediated suppressive effects. RBP-J deficiency–associated phenotypes could be genetically corrected by further deleting miRNA-17∼92 in macrophages. In the late phase, noneradicated pathogens in RBP-J KO mice recruited abundant IL-1β–expressing CD64+Ly6C+ colonic macrophages and thereby promoted persistence of ILC3-derived IL-22 to compensate for the impaired innate and adaptive immune responses, leading to ultimate clearance of pathogens. These results demonstrated that colonic macrophage–intrinsic RBP-J dynamically orchestrates intestinal immunity against pathogen infections by interfacing with key immune cells of T and innate lymphoid cell lineages.

scholarly journals Crosstalk between Dendritic Cells and Immune Modulatory Agents against Sepsis

Genes ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 323 ◽  
Author(s):  
Guoying Wang ◽  
Xianghui Li ◽  
Lei Zhang ◽  
Abualgasim Elgaili Abdalla ◽  
Tieshan Teng ◽  
...  
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Immune Responses ◽  
Critical Role ◽  
Innate Immune ◽  
Adaptive Immune Responses ◽  
Adaptive Immune ◽  
Th2 Responses ◽  
Novel Strategy

Dendritic cells (DCs) play a critical role in the immune system which sense pathogens and present their antigens to prime the adaptive immune responses. As the progression of sepsis occurs, DCs are capable of orchestrating the aberrant innate immune response by sustaining the Th1/Th2 responses that are essential for host survival. Hence, an in-depth understanding of the characteristics of DCs would have a beneficial effect in overcoming the obstacle occurring in sepsis. This paper focuses on the role of DCs in the progression of sepsis and we also discuss the reverse sepsis-induced immunosuppression through manipulating the DC function. In addition, we highlight some potent immunotherapies that could be used as a novel strategy in the early treatment of sepsis.

scholarly journals Differential Regulation of the Immune Response in the Spleen and Liver of Mice Infected withLeishmania donovani

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Rashmi Bankoti ◽  
Simona Stäger
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Host Defense ◽  
Defense Mechanisms ◽  
Leishmania Donovani ◽  
Differential Regulation ◽  
Therapeutic Interventions ◽  
Adaptive Immune Responses ◽  
Adaptive Immune ◽  
Novel Therapeutic

Immunity to pathogens requires generation of effective innate and adaptive immune responses.Leishmania donovanievades these host defense mechanisms to survive and persist in the host. A better understanding and identification of mechanisms thatL. donovaniemploys for its survival is critical for developing novel therapeutic interventions that specifically target the parasite. This paper will highlight some of the mechanisms that the parasite utilizes for its persistence and also discuss how the immune response is regulated.

scholarly journals Metal-induced delayed type hypersensitivity responses potentiate particle induced osteolysis in a sex and age dependent manner

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251885
Author(s):  
Lauryn Samelko ◽  
Marco Caicedo ◽  
Kyron McAllister ◽  
Joshua Jacobs ◽  
Nadim James Hallab
Keyword(s):  
Immune Responses ◽  
Nlrp3 Inflammasome ◽  
Inflammatory Responses ◽  
Delayed Type Hypersensitivity ◽  
Adaptive Immune Responses ◽  
Male And Female ◽  
Female Mice ◽  
Adaptive Immune ◽  
Caspase 1 ◽  
Deficient Mice

It is widely recognized that innate macrophage immune reactions to implant debris are central to the inflammatory responses that drive biologic implant failure over the long term. Less common, adaptive lymphocyte immune reactions to implant debris, such as delayed type hypersensitivity (DTH), can also affect implant performance. It is unknown which key patient factors, if any, mediate these adaptive immune responses that potentiate particle/macrophage mediated osteolysis. The objective of this investigation was to determine to what degree known adaptive immune responses to metal implant debris can affect particle-induced osteolysis (PIO); and if this pathomechanism is dependent on: 1) innate immune danger signaling, i.e., NLRP3 inflammasome activity, 2) sex, and/or 3) age. We used an established murine calvaria model of PIO using male and female wild-type C57BL/6 vs. Caspase-1 deficient mice as well as young (12–16 weeks old) vs. aged (18–24 months old) female and male C57BL/6 mice. After induction of metal-DTH, and Cobalt-alloy particle (ASTM F-75, 0.4um median diameter) calvaria challenge, bone resorption was assessed using quantitative micro-computed tomography (micro-CT) analysis and immune responses were assessed by measuring paw inflammation, lymphocyte transformation test (LTT) reactivity and adaptive immune cytokines IFN-gamma and IL-17 (ELISA). Younger aged C57BL/6 female mice exhibited the highest rate and severity of metal sensitivity lymphocyte responses that also translated into higher PIO compared to any other experimental group. The absence of inflammasome/caspase-1 activity significantly suppressed DTH metal-reactivity and osteolysis in both male and female Caspase-1 deficient mice. These murine model results indicate that young female mice are more predisposed to metal-DTH augmented inflammatory responses to wear debris, which is highly influenced by active NLRP3 inflammasome/caspase-1 danger signaling. If these results are clinically meaningful for orthopedic patients, then younger female individuals should be appropriately assessed and followed for DTH derived peri-implant complications.

scholarly journals COVID-19 and HIV-Associated Immune Reconstitution Inflammatory Syndrome: Emergence of Pathogen-Specific Immune Responses Adding Fuel to the Fire

2021 ◽  
Vol 12 ◽  
Author(s):  
Nabila Seddiki ◽  
Martyn French
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Immune Reconstitution Inflammatory Syndrome ◽  
Immune Reconstitution ◽  
Macrophage Activation ◽  
Adaptive Immune Response ◽  
T Cell Response ◽  
B Cell Differentiation ◽  
Adaptive Immune ◽  
Inflammatory Syndrome

Both coronavirus disease 2019 (COVID-19) and mycobacterial immune reconstitution inflammatory syndrome (IRIS) in patients with HIV-1 infection result from immunopathology that is characterized by increased production of multiple pro-inflammatory chemokines and cytokines associated with activation of myeloid cells (monocytes, macrophages and neutrophils). We propose that both conditions arise because innate immune responses generated in the absence of effective adaptive immune responses lead to monocyte/macrophage activation that is amplified by the emergence of a pathogen-specific adaptive immune response skewed towards monocyte/macrophage activating activity by the immunomodulatory effects of cytokines produced during the innate response, particularly interleukin-18. In mycobacterial IRIS, that disease-enhancing immune response is dominated by a Th1 CD4+ T cell response against mycobacterial antigens. By analogy, it is proposed that in severe COVID-19, amplification of monocyte/macrophage activation results from the effects of a SARS-CoV-2 spike protein antibody response with pro-inflammatory characteristics, including high proportions of IgG3 and IgA2 antibodies and afucosylation of IgG1 antibodies, that arises from B cell differentiation in an extra-follicular pathway promoted by activation of mucosa-associated invariant T cells. We suggest that therapy for the hyperinflammation underlying both COVID-19 and mycobacterial IRIS might be improved by targeting the immunomodulatory as well as the pro-inflammatory effects of the ‘cytokine storm’.

scholarly journals Lactate-Dependent Regulation of Immune Responses by Dendritic Cells and Macrophages

2021 ◽  
Vol 12 ◽  
Author(s):  
Indumathi Manoharan ◽  
Puttur D. Prasad ◽  
Muthusamy Thangaraju ◽  
Santhakumar Manicassamy
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Immune Cells ◽  
Adaptive Immune Responses ◽  
Effector Functions ◽  
Tissue Microenvironment ◽  
Adaptive Immune ◽  
Pathological Conditions ◽  
Recent Advances ◽  
Adaptive Immune Cells

For decades, lactate has been considered an innocuous bystander metabolite of cellular metabolism. However, emerging studies show that lactate acts as a complex immunomodulatory molecule that controls innate and adaptive immune cells’ effector functions. Thus, recent advances point to lactate as an essential and novel signaling molecule that shapes innate and adaptive immune responses in the intestine and systemic sites. Here, we review these recent advances in the context of the pleiotropic effects of lactate in regulating diverse functions of immune cells in the tissue microenvironment and under pathological conditions.

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