The skin, as the first physical barrier for invading pathogens, also serves as an immunologically active organ. Breaching the skin barrier is thus essential for pathogens to enter the body. The skin contains various immune responsive cells that initiate both the innate and adaptive immune response upon invasion. Activated immune cells help to regulate cytokine response and their differentiation to promote or suppress the crucial immune response against invading pathogens. Human herpes simplex viruses (HHSVs) are the oldest pathogen that can escape immune surveillance of the human host by a well-developed escape mechanism within ganglia, as their evolutionary strategy. In primary infection, a non-specific defense of the host initiates the response against the invading virion. The initial direct antiviral action of the host is regulated by activated macrophages, via the release of cytokines like tumor necrosis factor (TNF), and type-1 interferon (IFN-1). The host-derived cytokines including IFN-12, TNF, and IFN-1 in turn induce natural killer (NK) cells to release IFN-γ. Their positive feedback with synergistic interactions collectively releases nitric oxide (NO) and reactive oxygen species (ROS) against the invading virus. Simultaneously, the combination of cytokines, macrophages, and other cells activates the immune system to eliminate the pathogen. However, the virus has also evolved various mechanisms to counter the host defense strategies. This review will highlight virus-mediated skin infections, especially by HSV, and portray a detailed role of virus-induced cytokines in host-immunity to challenge the invading virion during mucocutaneous HSV infection. Further, this review will discuss the viral-interference on host defense to provide a simplistic overview of the complications of cutaneous HSV infection.

Rheumatoid arthritis (RA) is a complex autoimmune disorder characterized by a spectrum of hypersensitivity reactions, encompassing Type II, Type III, and Type IV responses. Firstly, RA is marked by Type II hypersensitivity reactions driven by autoantibodies, such as rheumatoid factor (RF) and anti-(cyclic) citrullinated protein antibodies (ACPAs). These autoantibodies serve not only as serological markers for RA but also actively participate in inflammation, bone erosion, and clinical outcomes, with concurrent activation of the complement system involving C1q, C3, and C5 components specifically linked to RA progression and bone damage. Secondly, RA exhibits traits of Type III hypersensitivity, marked by the formation of immune complexes inciting inflammatory reactions. Immunoglobulin G (IgG) autoantibodies like RF and ACPA play pivotal roles in immune complex formation and the ensuing inflammatory responses. RA also demonstrates Type IV hypersensitivity propelled by CD4⁺ T cells, encompassing T helper 1 (Th1) and Th17 subsets. Th1 cells release interferon (IFN)-γ, promoting proinflammatory cytokines, while Th17 cells secrete IL-17, IL-22, and granulocyte-macrophage colony-stimulating factor (GM-CSF), contributing to synovial inflammation, bone and cartilage damage, and angiogenesis. RA concurrently exhibits features of Type II, Type III, and Type IV hypersensitivity. It is crucial to comprehend the presence and complex interplay of hypersensitivity responses and specific immune cell subsets in RA to create precise and efficient therapeutic approaches for the management of this incapacitating autoimmune condition. Thus, in this review, we aim to provide a comprehensive overview of the hypersensitivity features of RA.

As the most severe novel infectious disease in this century, coronavirus disease 2019 (COVID-19) faces tremendous challenges due to the hysteresis of drugs and vaccine development. Elucidating the panoramic mechanism of coronavirus-host immune interaction is a strategy for disease surveillance, diagnosis, treatment, prevention, and immunity assessment of COVID-19. A robust carbon nanotube (CNT)-based photic vaccine technology contributes to address the core scientific issues of these challenges. This perspective states the latest prevention and control strategy of CNT-based photic vaccine and its broad-spectrum resistance to high transmissible and pathogenic variants. Furthermore, this perspective covers the potential immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) under the CNT-based photic vaccine intervention and finally evaluates its efficacy and the underlying interactive mechanisms. In the future, findings of the highly efficient and conservative T cell epitopes depending on an intelligent chem-physical modulation would provide a promising basis for the development of next generation vaccines. Ideally, these next generation vaccines are prone to be with the function of dynamic allostery responding to the chem-physical changing and present the allosteric epitopes which are affinity to the viral variation.

Testicular sperm maturation is critical for establishing male fertility. Spermatozoa undergo remodeling of sperm proteins and changes in lipid and ribonucleic acid composition during transport in the epididymal ducts, which play an important role in sperm maturation. The anatomy, epithelial cell types, physiological functions, and epigenetic inheritance of the epididymis are explored, and recent findings in epididymal research are analyzed. Suggesting possible directions for future research on the epididymis. Using the keywords “epididymis”, “sperm”, and “sperm maturation”, a search of the epididymis was performed through databases and official websites of journals related to reproduction. The epididymis was searched in databases and on the official websites of journals related to reproduction. This review introduces the characteristics of the epididymis, as well as the biological functions of cell types such as principal cells, clear cells, and basal cells, providing a detailed description of the overall physiological functions of the epididymis. It highlights current research hotspots in the field of epididymis, including single-cell analysis, epigenetics, and extracellular vesicles, aiming to offer a comprehensive understanding for beginners. The review emphasizes the importance of the epididymis, its impact on sperm maturation and subsequent embryo development, and how it advances research on epididymal diseases while providing new directions for the study and treatment strategies of infertility.

Dendritic cells (DCs) are part of the specific and innate immune system and present antigens for lymphocytes but also regulate the actions of cells of the innate immune system such as eosinophilic and neutrophilic granulocytes. There are several types of DCs, which might have opposite functions: some enhance an immune reaction, and others activate regulatory T (Treg) lymphocytes and thus can induce tolerance towards an antigen. Normally DCs migrate to regional lymph nodes and there they present modified antigens to cells of the immune system, however, in disease this might not function, resulting in the accumulation of DCs. The role of DCs in lung disease has not gotten much attention in the past, as investigations were predominantly focused on lymphocytes, macrophages, and granulocytes. Only in the last decades, DCs been more recognized. Several investigations are focusing on their role in immunotherapy in lung cancer, another focus is on inflammatory disorders including infections and allergies. In this review, non-tumor and non-infectious lung diseases with a focus on smoking-induced, autoimmune, and allergic diseases are discussed.

Repeated inoculation with messenger RNA (mRNA) vaccines elicits immunoglobulin G4 (IgG4) antibody production. Such an increase in the concentration of specific and non-specific IgG4 antibodies allows the growth of some types of cancer by blocking the activation of effector immune cells. This work proposes the hypothesis that cancer growth may be indirectly promoted by increased concentrations of non-specific IgG4 antibodies by the following mechanisms: 1) IgG4 antibodies can bind to anti-tumor IgG1 antibodies and block their interaction with receptors located on effector cells, thus preventing the destruction of cancer cells, 2) IgG4 can interact with fragment crystallizable gamma receptor IIb (FcγRIIB) inhibitory receptors, thus reducing effector functions of innate immune cells, and 3) targeting of specific epitopes by IgG4 could be oncogenic by inducing the production of a microenvironment that can promote cancer development. This article reviews the supporting literature and suggests several experimental protocols to evaluate this hypothesis in the context of repeated inoculation with mRNA vaccines. Additionally, this work proposes some management options aimed at reducing the unfavorable molecular consequences that could mediate cancer development when encountering high concentrations of IgG4 antibodies.

Ebola virus (EBOV) is a zoonotic virus comprising of six known different species, designated within the family Filoviridae and genus Ebolavirus. The first recorded outbreak of an EBOV disease (EVD) was in Yambuku, Zaire EBOV (ZEBOV) in 1976, followed by the Sudan EBOV (SUDV) later that year. Outbreaks have been increasing throughout the 21st century, and mortality rates can reach up to 90%. Such extraordinary virulence is evidenced by a few pathogens, similar to the Marburg virus (MARV) that originated in Uganda and was first detected in Germany in 1967. The virulent nature of filovirus disease has established these related viruses as a formidable global concern. There are currently four types of Ebolaviridae species known to infect humans, with two more recently identified in other animals that are genomically different concerning cellular pathogenesis or aetiology of disease. Recent advances in understanding the pathogenesis of filovirus disease infections have been remarkable, yet the immunological response to filovirus infection remains unknown. Scientific analysis of cellular mechanisms can provide insight into virulence factors utilised by other pathogenic viruses that also cause febrile illness with occasional haemorrhagic fever in humans. In this review, a brief summary of EBOV protein structure and functional cellular effects is covered. The role of innate and adaptive immune cells known since 1976 is considered with the relevance and implications of immunological proteins measured by cluster of differentiation (CD) molecule, alongside cytokine, chemokine, and other biologically relevant pathways, and through genetic research. A thorough understanding of immunological correlates affecting host responses to EBOV will facilitate clinical and applied research knowledge, contributing to protection against potential public health threats.