Microorganisms

Review

29 pages, 8331 KiB

Open AccessReview

Natural Killer Cells and Cytotoxic T Cells: Complementary Partners against Microorganisms and Cancer

by Aristo Vojdani, Sadi Koksoy, Elroy Vojdani, Mark Engelman, Carina Benzvi and Aaron Lerner

Microorganisms 2024, 12(1), 230; https://doi.org/10.3390/microorganisms12010230 - 22 Jan 2024

Cited by 7 | Viewed by 4117

Natural killer (NK) cells and cytotoxic T (CD8⁺) cells are two of the most important types of immune cells in our body, protecting it from deadly invaders. While the NK cell is part of the innate immune system, the CD8⁺ [...] Read more.

Natural killer (NK) cells and cytotoxic T (CD8⁺) cells are two of the most important types of immune cells in our body, protecting it from deadly invaders. While the NK cell is part of the innate immune system, the CD8⁺ cell is one of the major components of adaptive immunity. Still, these two very different types of cells share the most important function of destroying pathogen-infected and tumorous cells by releasing cytotoxic granules that promote proteolytic cleavage of harmful cells, leading to apoptosis. In this review, we look not only at NK and CD8⁺ T cells but also pay particular attention to their different subpopulations, the immune defenders that include the CD56⁺CD16^dim, CD56^dimCD16⁺, CD57⁺, and CD57⁺CD16⁺ NK cells, the NKT, CD57⁺CD8⁺, and KIR⁺CD8⁺ T cells, and ILCs. We examine all these cells in relation to their role in the protection of the body against different microorganisms and cancer, with an emphasis on their mechanisms and their clinical importance. Overall, close collaboration between NK cells and CD8⁺ T cells may play an important role in immune function and disease pathogenesis. The knowledge of how these immune cells interact in defending the body against pathogens and cancers may help us find ways to optimize their defensive and healing capabilities with methods that can be clinically applied. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

► Show Figures

Figure 1

13 pages, 3130 KiB

Open AccessReview

Encystation and Stress Responses under the Control of Ubiquitin-like Proteins in Pathogenic Amoebae

by Ascel Samba-Louaka, Elisabeth Labruyère, Mariette Matondo, Marie Locard-Paulet, Jean-Christophe Olivo-Marin and Nancy Guillen

Microorganisms 2023, 11(11), 2670; https://doi.org/10.3390/microorganisms11112670 - 31 Oct 2023

Cited by 2 | Viewed by 1962

Abstract

Amoebae found in aquatic and terrestrial environments encompass various pathogenic species, including the parasite Entamoeba histolytica and the free-living Acanthamoeba castellanii. Both microorganisms pose significant threats to public health, capable of inducing life-threatening effects on humans. These amoebae exist in two cellular [...] Read more.

Amoebae found in aquatic and terrestrial environments encompass various pathogenic species, including the parasite Entamoeba histolytica and the free-living Acanthamoeba castellanii. Both microorganisms pose significant threats to public health, capable of inducing life-threatening effects on humans. These amoebae exist in two cellular forms: trophozoites and cysts. The trophozoite stage is the form used for growth and reproduction while the cyst stage is the resistant and disseminating form. Cysts occur after cellular metabolism slowdown due to nutritional deprivation or the appearance of environmental conditions unfavourable to the amoebae’s growth and division. The initiation of encystation is accompanied by the activation of stress responses, and scarce data indicate that encystation shares factors and mechanisms identified in stress responses occurring in trophozoites exposed to toxic compounds derived from human immune defence. Although some “omics” analyses have explored how amoebae respond to diverse stresses, these studies remain limited and rarely report post-translational modifications that would provide knowledge on the molecular mechanisms underlying amoebae-specific stress responses. In this review, we discuss ubiquitin-like proteins associated with encystation and cell survival during oxidative damage. We aim to shed light on the signalling pathways involved in amoebic defence mechanisms, with a focus on their potential clinical implications against pathogenic amoebae, addressing the pressing need for effective therapies. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

► Show Figures

Figure 1

13 pages, 287 KiB

Open AccessReview

Mind the Gap—A Perspective on Strategies for Protecting against Bacterial Infections during the Period from Infection to Eradication

by Yoav Gal, Hadar Marcus, Emanuelle Mamroud and Ronit Aloni-Grinstein

Microorganisms 2023, 11(7), 1701; https://doi.org/10.3390/microorganisms11071701 - 29 Jun 2023

Cited by 1 | Viewed by 1524

Abstract

The emergence of antibiotic-resistant bacteria is a pressing public health concern, highlighting the need for alternative approaches to control bacterial infections. Promising approaches include the development of therapeutic vaccines and the utilization of innate immune activation techniques, which may prove useful in conjunction [...] Read more.

The emergence of antibiotic-resistant bacteria is a pressing public health concern, highlighting the need for alternative approaches to control bacterial infections. Promising approaches include the development of therapeutic vaccines and the utilization of innate immune activation techniques, which may prove useful in conjunction with antibiotics, as well as other antibacterial modalities. However, innate activation should be fast and self- or actively- contained to prevent detrimental consequences. TLR ligand adjuvants are effective at rapidly activating, within minutes to hours, the innate immune system by inducing cytokine production and other signaling molecules that bolster the host’s immune response. Neutrophils serve as the first line of defense against invading pathogens by capturing and destroying them through various mechanisms, such as phagocytosis, intracellular degradation, and the formation of NETs. Nutritional immunity is another host defense mechanism that limits the availability of essential metals, such as iron, from invading bacterial pathogens. Thus, iron starvation has been proposed as a potential antibacterial strategy. In this review, we focus on approaches that have the potential to enhance rapid and precise antibacterial responses, bridging the gap between the onset of infection and the elimination of bacteria, hence limiting the infection by antibiotic-resistant bacteria. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

21 pages, 1567 KiB

Open AccessReview

The Neonatal Immune System and Respiratory Pathogens

by Colleen J. Sedney and Eric T. Harvill

Microorganisms 2023, 11(6), 1597; https://doi.org/10.3390/microorganisms11061597 - 16 Jun 2023

Cited by 2 | Viewed by 3879

Abstract

Neonates are more susceptible to some pathogens, particularly those that cause infection in the respiratory tract. This is often attributed to an incompletely developed immune system, but recent work demonstrates effective neonatal immune responses to some infection. The emerging view is that neonates [...] Read more.

Neonates are more susceptible to some pathogens, particularly those that cause infection in the respiratory tract. This is often attributed to an incompletely developed immune system, but recent work demonstrates effective neonatal immune responses to some infection. The emerging view is that neonates have a distinctly different immune response that is well-adapted to deal with unique immunological challenges of the transition from a relatively sterile uterus to a microbe-rich world, tending to suppress potentially dangerous inflammatory responses. Problematically, few animal models allow a mechanistic examination of the roles and effects of various immune functions in this critical transition period. This limits our understanding of neonatal immunity, and therefore our ability to rationally design and develop vaccines and therapeutics to best protect newborns. This review summarizes what is known of the neonatal immune system, focusing on protection against respiratory pathogens and describes challenges of various animal models. Highlighting recent advances in the mouse model, we identify knowledge gaps to be addressed. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

► Show Figures

Figure 1

13 pages, 326 KiB

Open AccessReview

Severe Combined Immunodeficiency—Classification, Microbiology Association and Treatment

by Angel A. Justiz-Vaillant, Darren Gopaul, Patrick Eberechi Akpaka, Sachin Soodeen and Rodolfo Arozarena Fundora

Microorganisms 2023, 11(6), 1589; https://doi.org/10.3390/microorganisms11061589 - 15 Jun 2023

Cited by 7 | Viewed by 2794

Abstract

Severe combined immunodeficiency (SCID) is a primary inherited immunodeficiency disease that presents before the age of three months and can be fatal. It is usually due to opportunistic infections caused by bacteria, viruses, fungi, and protozoa resulting in a decrease in number and [...] Read more.

Severe combined immunodeficiency (SCID) is a primary inherited immunodeficiency disease that presents before the age of three months and can be fatal. It is usually due to opportunistic infections caused by bacteria, viruses, fungi, and protozoa resulting in a decrease in number and impairment in the function of T and B cells. Autosomal, X-linked, and sporadic forms exist. Evidence of recurrent opportunistic infections and lymphopenia very early in life should prompt immunological investigation and suspicion of this rare disorder. Adequate stem cell transplantation is the treatment of choice. This review aimed to provide a comprehensive approach to the microorganisms associated with severe combined immunodeficiency (SCID) and its management. We describe SCID as a syndrome and summarize the different microorganisms that affect children and how they can be investigated and treated. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

24 pages, 903 KiB

Open AccessReview

Microbiota Regulates Pancreatic Cancer Carcinogenesis through Altered Immune Response

by Yihan Chai, Zhengze Huang, Xuqiu Shen, Tianyu Lin, Yiyin Zhang, Xu Feng, Qijiang Mao and Yuelong Liang

Microorganisms 2023, 11(5), 1240; https://doi.org/10.3390/microorganisms11051240 - 8 May 2023

Cited by 10 | Viewed by 3738

Abstract

The microbiota is present in many parts of the human body and plays essential roles. The most typical case is the occurrence and development of cancer. Pancreatic cancer (PC), one of the most aggressive and lethal types of cancer, has recently attracted the [...] Read more.

The microbiota is present in many parts of the human body and plays essential roles. The most typical case is the occurrence and development of cancer. Pancreatic cancer (PC), one of the most aggressive and lethal types of cancer, has recently attracted the attention of researchers. Recent research has revealed that the microbiota regulates PC carcinogenesis via an altered immune response. Specifically, the microbiota, in several sites, including the oral cavity, gastrointestinal tract, and pancreatic tissue, along with the numerous small molecules and metabolites it produces, influences cancer progression and treatment by activating oncogenic signaling, enhancing oncogenic metabolic pathways, altering cancer cell proliferation, and triggering chronic inflammation that suppresses tumor immunity. Diagnostics and treatments based on or in combination with the microbiota offer novel insights to improve efficiency compared with existing therapies. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

► Show Figures

Figure 1

15 pages, 1658 KiB

Open AccessReview

A Review of the Bacterial Phosphoproteomes of Beneficial Microbes

by Sooa Lim

Microorganisms 2023, 11(4), 931; https://doi.org/10.3390/microorganisms11040931 - 3 Apr 2023

Cited by 2 | Viewed by 2261

Abstract

The number and variety of protein post-translational modifications (PTMs) found and characterized in bacteria over the past ten years have increased dramatically. Compared to eukaryotic proteins, most post-translational protein changes in bacteria affect relatively few proteins because the majority of modified proteins exhibit [...] Read more.

The number and variety of protein post-translational modifications (PTMs) found and characterized in bacteria over the past ten years have increased dramatically. Compared to eukaryotic proteins, most post-translational protein changes in bacteria affect relatively few proteins because the majority of modified proteins exhibit substoichiometric modification levels, which makes structural and functional analyses challenging. In addition, the number of modified enzymes in bacterial species differs widely, and degrees of proteome modification depend on environmental conditions. Nevertheless, evidence suggests that protein PTMs play essential roles in various cellular processes, including nitrogen metabolism, protein synthesis and turnover, the cell cycle, dormancy, spore germination, sporulation, persistence, and virulence. Additional investigations on protein post-translational changes will undoubtedly close knowledge gaps in bacterial physiology and create new means of treating infectious diseases. Here, we describe the role of the post-translation phosphorylation of major bacterial proteins and review the progress of research on phosphorylated proteins depending on bacterial species. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

► Show Figures

Figure 1

17 pages, 353 KiB

Open AccessReview

Candida spp. DNA Extraction in the Age of Molecular Diagnosis

by Smaranda Ioana Codreanu and Cristina Nicoleta Ciurea

Microorganisms 2023, 11(4), 818; https://doi.org/10.3390/microorganisms11040818 - 23 Mar 2023

Cited by 4 | Viewed by 2821

Abstract

The standard procedure for the detection of candidemia is blood culture, a method that might require 3–5 days for a positive result. Compared with culturing, molecular diagnosis techniques can provide faster diagnosis. The current paper aimed to present the main strengths and constraints [...] Read more.

The standard procedure for the detection of candidemia is blood culture, a method that might require 3–5 days for a positive result. Compared with culturing, molecular diagnosis techniques can provide faster diagnosis. The current paper aimed to present the main strengths and constraints of current molecular techniques for Candida spp. DNA extraction, analyzing their efficiency from a time, price, and ease of usage point of view. A comprehensive search was conducted using the PubMed NIH database for peer-reviewed full-text articles published before October 2022. The studies provided adequate data on the diagnosis of the infection with the Candida spp. DNA extraction is a relevant step in yielding pure qualitative DNA to be amplified in molecular diagnostic techniques. The most used fungal DNA extraction strategies are: mechanical (bead beating, ultrasonication, steel-bullet beating), enzymatic (proteinase K, lysozyme, lyticase), and chemical extraction (formic acid, liquid nitrogen, ammonium chloride). More clinical studies are needed to formulate adequate guidelines for fungal DNA extraction as the current paper highlighted discrepancies in the reported outcome. Full article

(This article belongs to the Special Issue Latest Review Papers in Molecular Microbiology and Immunology 2023)

Journal Menu

Journal Browser

Latest Review Papers in Molecular Microbiology and Immunology 2023

Share This Special Issue

Special Issue Editor

Special Issue Information

Benefits of Publishing in a Special Issue

Published Papers (8 papers)

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI