This review provides a detailed examination of CD4+ T lymphocyte subsets, crucial components of the immune system originating from the thymus. This study explores the distinct roles and mechanisms of various T helper (Th) cell subsets, including Th1, Th2, Th17, Th22, regulatory T cells (Tregs), Th9, and T follicular helper (Tfh) cells, focusing on their induction by specific cytokines, regulation by transcription factors, and the production of post-induction cytokines. The study traces the historical origins of Th lymphocyte research, emphasizing the unique cytokine profiles and functional implications of each subset in immune regulation and pathology, including autoimmune diseases, allergies, and cancer. Key findings include the delineation of cytokine-mediated induction processes, highlighting factors like interferon-gamma (IFN-γ), interleukin-4 (IL-4), transforming growth factor-beta (TGF-β), and IL-6. The review delves into transcription factors such as T-box transcription factor 21 (T-bet), GATA binding protein 3 (GATA3), and forkhead box P3 (Foxp3), underlying the lineage-specific development of these cells, and discusses the significant roles of post-induction cytokines. The research underscores the clinical relevance of CD4+ T cell subset dysregulation in various diseases, advocating for a nuanced understanding of these subsets for potential therapeutic advancements in immune-related disorders.

Cancer stem cells (CSCs) are a unique population of tumor cells with stem cell-like properties. They are believed to be involved in drug resistance, potential therapy failure, tumor relapse after treatment, and ultimately reduced overall survival of cancer patients. One of the causal factors that may lead to CSC formation is chromosomal instability (CIN), a dynamic event leading to numerical and structural changes in the chromosomes. The CIN is also proposed to aid the maintenance of CSCs, contribute towards their heterogeneity, and facilitate their immune escape. However, the role of CIN in the modulation of the immune system in tumors remains contradictory. Studies have revealed that it can lead to both activation and suppression of the immune system. Previous literature suggests that the CIN, CSCs, and cancer immunity (3Cs), interact with and complement each other to create a pro-tumor environment. However, the mechanisms underlying such an interaction are poorly understood. So, in this review article, an attempt has been made to understand the nature of the interaction between the triad of CIN, CSC, and the immune response in tumors and some of the pathways governing the same. Understanding the above may be a positive step towards the complete cure for malignant diseases.

Dendritic cells (DCs) play an important role in the formation of the immune response, and they are involved in the pathogenesis of autoimmune diseases. Targeting DCs has thus emerged as a new therapeutic modality in the management of inflammatory and autoimmune diseases. DCs can be manipulated ex vivo and then injected back into humans to suppress the immune response. They can also be manipulated in vivo by delivering specific molecules into the DCs. Co-stimulatory molecules that shape DCs interaction with T cells can also be targeted to suppress immunity. This review tackles the latest advances in each of the 3 presented approaches.

Primary immune regulatory disorders (PIRDs) constitute a subset of inborn errors of immunity and are characterized by lymphoproliferation, autoimmunity, malignancy, and infection. Unlike classical primary immune deficiencies, initial symptoms of PIRDs can manifest as autoimmunity such as cytopenias or enteropathy, which can often prove resistant to conventional treatments and occur years prior to the onset of infectious complications. Raising awareness about PIRDs among specialists and adopting a multidisciplinary approach is crucial for early diagnosis, intervention, and potential prevention of severe organ damage. Significant progress has been made in identifying several PIRDs, which has contributed to a more comprehensive comprehension of their underlying immunological mechanisms. This knowledge has paved the way for targeted therapies focusing on specific molecules, which tend to offer superior disease control compared to traditional immunosuppressants. This review, informed by the latest literature, explores prevalent PIRDs, detailing their clinical manifestations and recent advancements in treatment modalities.

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.

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.

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.