Carbohydrate Immune Adjuvants in Subunit Vaccines

Modern subunit vaccines are composed of antigens and a delivery system and/or adjuvant (immune stimulator) that triggers the desired immune responses. Adjuvants mimic pathogen-associated molecular patterns (PAMPs) that are typically associated with infections. Carbohydrates displayed on the surface of pathogens are often recognized as PAMPs by receptors on antigen-presenting cells (APCs). Consequently, carbohydrates and their analogues have been used as adjuvants and delivery systems to promote antigen transport to APCs. Carbohydrates are biocompatible, usually nontoxic, biodegradable, and some are mucoadhesive. As such, carbohydrates and their derivatives have been intensively explored for the development of new adjuvants. This review assesses the immunological functions of carbohydrate ligands and their ability to enhance systemic and mucosal immune responses against co-administered antigens. The role of carbohydrate-based adjuvants/delivery systems in the development of subunit vaccines is discussed in detail.

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Modulation of Immune Responses by Exosomes Derived from Antigen-Presenting Cells

Clinical Medicine Insights Pathology ◽

10.4137/cpath.s39925 ◽

2016 ◽

Vol 9s1 ◽

pp. CPath.S39925 ◽

Cited By ~ 14

Author(s):

Botros B. Shenoda ◽

Seena K. Ajit

Keyword(s):

Immune Response ◽

Immune Responses ◽

Antigen Presenting Cells ◽

Protective Role ◽

Cell Responses ◽

Therapeutic Benefits ◽

Peptide Complexes ◽

Non Coding Rnas ◽

Antigen Presenting

Exosome-mediated signaling is important in mediating the inflammatory response. To exert their biological or pathophysiological functions in the recipient cells, exosomes deliver a diverse array of biomacromolecules including long and short coding and non-coding RNAs, proteins, and lipids. Exosomes secreted by antigen-presenting cells can confer therapeutic benefits by attenuating or stimulating the immune response. Exosomes play a crucial role in carrying and presenting functional major histocompatibility peptide complexes to modulate antigen-specific T cell responses. Exosomes from Dendritic Cells (DCs) can activate T and B cells and have been explored for their immunostimulatory properties in cancer therapy. The immunosuppressive properties of exosomes derived from macrophages and DCs can reduce inflammation in animal models for several inflammatory disorders. This review focuses on the protective role of exosomes in attenuating inflammation or augmenting immune response, emphasizing studies on exosomes derived from DCs and macrophages.

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Could Antigen Presenting Cells Represent a Protective Element during SARS-CoV-2 Infection in Children?

Pathogens ◽

10.3390/pathogens10040476 ◽

2021 ◽

Vol 10 (4) ◽

pp. 476

Author(s):

Rita Lauro ◽

Natasha Irrera ◽

Ali H. Eid ◽

Alessandra Bitto

Keyword(s):

Immune Responses ◽

Immune Cells ◽

Molecular Mechanisms ◽

Antigen Presenting Cells ◽

Immune Responsiveness ◽

Protective Element ◽

Adults And Children ◽

Antigen Presenting ◽

Two Populations

Antigen Presenting Cells (APC) are immune cells that recognize, process, and present antigens to lymphocytes. APCs are among the earliest immune responders against an antigen. Thus, in patients with COVID-19, a disease caused by the newly reported SARS-CoV-2 virus, the role of APCs becomes increasingly important. In this paper, we dissect the role of these cells in the fight against SARS-CoV-2. Interestingly, this virus appears to cause a higher mortality among adults than children. This may suggest that the immune system, particularly APCs, of children may be different from that of adults, which may then explain differences in immune responses between these two populations, evident as different pathological outcome. However, the underlying molecular mechanisms that differentiate juvenile from other APCs are not well understood. Whether juvenile APCs are one reason why children are less susceptible to SARS-CoV-2 requires much attention. The goal of this review is to examine the role of APCs, both in adults and children. The molecular mechanisms governing APCs, especially against SARS-CoV-2, may explain the differential immune responsiveness in the two populations.

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The Role of Dendritic and Endothelial Cells in Cardiorenal Syndrome

Cardiorenal Medicine ◽

10.1159/000485937 ◽

2018 ◽

Vol 8 (2) ◽

pp. 92-104 ◽

Cited By ~ 6

Author(s):

Grazia Maria Virzì ◽

Jun Zhang ◽

Federico Nalesso ◽

Claudio Ronco ◽

Peter A. McCullough

Keyword(s):

Endothelial Cells ◽

Immune Responses ◽

Antigen Presenting Cells ◽

Cardiorenal Syndrome ◽

Novel Therapies ◽

Adaptive Immune Responses ◽

Adaptive Immune ◽

Prevention And Treatment ◽

Antigen Presenting

Backgrounds: Dendritic cells (DCs) are antigen-presenting cells that play a central role in innate and adaptive immune responses; however, the cross talk between cardiac and renal DCs in cardiorenal syndrome (CRS) has not yet been fully elucidated. In this setting, endothelial cells (ECs) also contribute to immune responses. Summary: DC and EC activation and dysfunction have a central role in the pathogenesis of CRS. Regarding immune responses in CRS, it is unknown whether ECs may serve as antigen-presenting cells or act synergistically with DCs to actively participate in innate and adaptive immune responses. This review first focuses on the burden of concomitant heart and renal DCs in the context of CRS; it examines what is known of DCs in animal models, and proposes a central role for DCs in all types of CRS. Second, this review briefly describes the role of ECs in the context of CRS. Key Messages: Understanding the role of DCs and ECs in immune response could lead to the development of novel therapies for the prevention and treatment of CRS.

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Parasitic Infections: A Role for C-Type Lectins Receptors

BioMed Research International ◽

10.1155/2013/456352 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 25

Author(s):

Alicia Vázquez-Mendoza ◽

Julio César Carrero ◽

Miriam Rodriguez-Sosa

Keyword(s):

Dendritic Cells ◽

Immune Responses ◽

Innate Immune ◽

Parasitic Infections ◽

Dependent Manner ◽

Innate Immune Responses ◽

Parasite Infections ◽

Antigen Presenting ◽

Molecular Patterns

Antigen-presenting cells (APCs) sense the microenvironment through several types of receptors that recognize pathogen-associated molecular patterns. In particular, C-type lectins receptors (CLRs), which are expressed by distinct subsets of dendritic cells (DCs) and macrophages (MØs), recognize and internalize specific carbohydrate antigens in a Ca2+-dependent manner. The targeting of these receptors is becoming an efficient strategy for parasite recognition. However, relatively little is known about how CLRs are involved in both pathogen recognition and the internalization of parasites. The role of CLRs in parasite infections is an area of considerable interest because this research will impact our understanding of the initiation of innate immune responses, which influences the outcome of specific immune responses. This paper attempts to summarize our understanding of the effects of parasites’ interactions with CLRs.

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Dual role of antigen-presenting cells during Ebola virus infection

10.26226/morressier.5991c407d462b80292388b8b ◽

2017 ◽

Author(s):

Emily Nelson

Keyword(s):

Virus Infection ◽

Ebola Virus ◽

Antigen Presenting Cells ◽

Dual Role ◽

Antigen Presenting ◽

Ebola Virus Infection

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The Role of Macrophages in the Host’s Defense against Sporothrix schenckii

Pathogens ◽

10.3390/pathogens10070905 ◽

2021 ◽

Vol 10 (7) ◽

pp. 905

Author(s):

Estela Ruiz-Baca ◽

Armando Pérez-Torres ◽

Yolanda Romo-Lozano ◽

Daniel Cervantes-García ◽

Carlos A. Alba-Fierro ◽

...

Keyword(s):

Immune Responses ◽

Macrophage Polarization ◽

Sporothrix Schenckii ◽

Macrophage Cell ◽

Cell Recruitment ◽

Host Pathogen Interaction ◽

Interaction Processes ◽

Host Pathogen ◽

Molecular Patterns

The role of immune cells associated with sporotrichosis caused by Sporothrix schenckii is not yet fully clarified. Macrophages through pattern recognition receptors (PRRs) can recognize pathogen-associated molecular patterns (PAMPs) of Sporothrix, engulf it, activate respiratory burst, and secrete pro-inflammatory or anti-inflammatory biological mediators to control infection. It is important to consider that the characteristics associated with S. schenckii and/or the host may influence macrophage polarization (M1/M2), cell recruitment, and the type of immune response (1, 2, and 17). Currently, with the use of new monocyte-macrophage cell lines, it is possible to evaluate different host–pathogen interaction processes, which allows for the proposal of new mechanisms in human sporotrichosis. Therefore, in order to contribute to the understanding of these host–pathogen interactions, the aim of this review is to summarize and discuss the immune responses induced by macrophage-S. schenckii interactions, as well as the PRRs and PAMPs involved during the recognition of S. schenckii that favor the immune evasion by the fungus.

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