The rise in global life expectancy has led to an increase in the older population, presenting significant challenges in managing infectious diseases. Aging affects the innate and adaptive immune systems, resulting in chronic low-grade inflammation (inflammaging) and immune function decline (immunosenescence). These changes would impair defense mechanisms, increase susceptibility to infections and reduce vaccine efficacy in older adults. Cellular senescence exacerbates these issues by releasing pro-inflammatory factors, further perpetuating chronic inflammation. Moreover, comorbidities, such as cardiovascular disease and diabetes, which are common in older adults, amplify immune dysfunction, while immunosuppressive medications further complicate responses to infections. This review explores the molecular and cellular mechanisms driving inflammaging and immunosenescence, focusing on genomic instability, telomere attrition, and mitochondrial dysfunction. Additionally, we discussed how aging-associated immune alterations influence responses to bacterial, viral, and parasitic infections and evaluated emerging antiaging strategies, aimed at mitigating these effects to improve health outcomes in the aging population.
Humans ; Aging/physiology* ; Communicable Diseases/immunology* ; Immunosenescence/physiology* ; Inflammation/immunology* ; Genomic Instability

The Qa-1 in mice is homologous to human leukocyte antigen E(HLA-E), and both of them belong to the non-classical major histocompatibility complex I b(MHC-I b) molecules. Qa-1 is capable of presenting self or exogenous antigen peptides to interact with two distinct receptors, namely T cell receptor (TCR) and natural killer cell group 2 member A (or C) (NKG2A/C), thus playing an important role in immune response and regulation. Qa-1-restricted regulatory CD8⁺ T cell (CD8⁺ Treg) is one of the most studied CD8⁺ Treg subgroups, which can maintain immune homeostasis and autoimmune tolerance by exerting immunosuppressive effects. Consequently, Qa-1-restricted CD8⁺Treg cells are closely associated with the occurrence and development of various clinical diseases, such as tumors, infections, autoimmune diseases, and transplant rejections. This paper provides a comprehensive review of the phenotypic characteristics, functional effects, regulatory mechanisms of Qa-1-restricted CD8⁺ Treg cells, as well as the latest research progresses of Qa-1-restricted CD8⁺ Treg cells involved in the pathogenesis of infectious diseases.
Humans ; Animals ; T-Lymphocytes, Regulatory/immunology* ; Histocompatibility Antigens Class I/immunology* ; CD8-Positive T-Lymphocytes/immunology* ; Communicable Diseases/immunology*

Allergy and Immunology ; Ambulatory Care ; Autoimmune Diseases/therapy* ; COVID-19 ; Communicable Disease Control ; Connective Tissue Diseases/therapy* ; Delivery of Health Care/methods* ; Dermatology ; Humans ; Immunosuppressive Agents/therapeutic use* ; Patient Selection ; SARS-CoV-2 ; Singapore ; Skin Diseases, Vesiculobullous/therapy* ; Telemedicine/methods* ; Tertiary Care Centers ; Vasculitis/therapy*

The γδ T cells are unconventional lymphocytes that function in both innate and adaptive immune responses against various intracellular and infectious stresses. The γδ T cells can be exploited as cancer-killing effector cells since γδ TCRs recognize MHC-like molecules and growth factor receptors that are upregulated in cancer cells, and γδ T cells can differentiate into cytotoxic effector cells. However, γδ T cells may also promote tumor progression by secreting IL-17 or other cytokines. Therefore, it is essential to understand how the differentiation and homeostasis of γδ T cells are regulated and whether distinct γδ T cell subsets have different functions. Human γδ T cells are classified into Vδ2 and non-Vδ2 γδ T cells. The majority of Vδ2 γδ T cells are Vγ9δ2 T cells that recognize pyrophosphorylated isoprenoids generated by the dysregulated mevalonate pathway. In contrast, Vδ1 T cells expand from initially diverse TCR repertoire in patients with infectious diseases and cancers. The ligands of Vδ1 T cells are diverse and include the growth factor receptors such as endothelial protein C receptor. Both Vδ1 and Vδ2 γδ T cells are implicated to have immunotherapeutic potentials for cancers, but the detailed elucidation of the distinct characteristics of 2 populations will be required to enhance the immunotherapeutic potential of γδ T cells. Here, we summarize recent progress regarding cancer immunology of human γδ T cells, including their development, heterogeneity, and plasticity, the putative mechanisms underlying ligand recognition and activation, and their dual effects on tumor progression in the tumor microenvironment.
Allergy and Immunology ; Communicable Diseases ; Cytokines ; Homeostasis ; Humans ; Interleukin-17 ; Ligands ; Lymphocytes ; Mevalonic Acid ; Plastics ; Population Characteristics ; Protein C ; Receptors, Antigen, T-Cell, gamma-delta ; Receptors, Growth Factor ; T-Lymphocyte Subsets ; T-Lymphocytes ; Terpenes ; Tumor Microenvironment

Emerging infectious diseases (EIDs) pose a major threat to public health and security. Given the dynamic nature and significant impact of EIDs, the most effective way to prevent and protect against them is to develop vaccines in advance. Systems biology approaches provide an integrative way to understand the complex immune response to pathogens. They can lead to a greater understanding of EID pathogenesis and facilitate the evaluation of newly developed vaccine-induced immunity in a timely manner. In recent years, advances in high throughput technologies have enabled researchers to successfully apply systems biology methods to analyze immune responses to a variety of pathogens and vaccines. Despite recent advances, computational and biological challenges impede wider application of systems biology approaches. This review highlights recent advances in the fields of systems immunology and vaccinology, and presents ways that systems biology-based platforms can be applied to accelerate a deeper understanding of the molecular mechanisms of immunity against EIDs.
*Communicable Diseases, Emerging ; Humans ; *Immunity ; Research ; Systems Biology/*methods ; Vaccines/*immunology

Infectious diseases can be caused by multiple pathogens, which can produce specific immune response in human body. The immune response produced by T cells is cellular immunity, which plays an important role in the anti-infection process of human body, and can participate in immunological protection and cause immunopathology. The outcome of various infectious diseases is closely related to cellular immune function, especially the function of T cells. Jurkat cells belong to the human acute T lymphocyte leukemia cell line. Jurkat cell model can simulate the function T lymphocytes, so it is widely used in the in vitro studies of T cell signal transduction, cytokines, and receptor expression, and can provide reference and guidance for the treatment of various infectious diseases and the research on their pathogenesis. The Jurkat cell model has been widely used in the in vitro studies of viral diseases and atypical pathogens, but parasitic infection studies using the Jurkat cell model are still rare. This article reviews advances in the application of Jurkat cell model in the research on infectious diseases.
Communicable Diseases ; immunology ; Deltaretrovirus Infections ; immunology ; Enterovirus A, Human ; Enterovirus Infections ; immunology ; Epstein-Barr Virus Infections ; immunology ; HIV Infections ; immunology ; Humans ; Jurkat Cells ; immunology ; T-Lymphocytes ; immunology

The hygiene hypothesis (HH) proposed by Strachan in 1989 was expanded to explain the inverse association between the occurrence of allergy disorders and the risk of infectious diseases and parasite infestation. The microflora hypothesis (MH) suggests that gut microbial dysbiosis in early life might trigger hypersensitivity disorders. The sharing concept of both HH and MH is gene-environment interaction, which is also a key concept in epigenetics. The amalgamation of epidemiology and epigenetics has created a scientific discipline termed epigenetic epidemiology. To accomplish an era of gene-environment-wide interaction studies, it is necessary to launch a national human epigenome project.
Allergy and Immunology ; Communicable Diseases ; Dysbiosis ; Epidemiology* ; Epigenomics* ; Gastrointestinal Microbiome ; Gene-Environment Interaction ; Humans ; Hygiene Hypothesis ; Hygiene* ; Hypersensitivity ; Parasites

The hygiene hypothesis (HH) proposed by Strachan in 1989 was expanded to explain the inverse association between the occurrence of allergy disorders and the risk of infectious diseases and parasite infestation. The microflora hypothesis (MH) suggests that gut microbial dysbiosis in early life might trigger hypersensitivity disorders. The sharing concept of both HH and MH is gene-environment interaction, which is also a key concept in epigenetics. The amalgamation of epidemiology and epigenetics has created a scientific discipline termed epigenetic epidemiology. To accomplish an era of gene-environment-wide interaction studies, it is necessary to launch a national human epigenome project.
Allergy and Immunology ; Communicable Diseases ; Dysbiosis ; Epidemiology ; Epigenomics ; Gastrointestinal Microbiome ; Gene-Environment Interaction ; Humans ; Hygiene Hypothesis ; Hygiene ; Hypersensitivity ; Parasites

The importance of vaccine on public health is related to the herd protection related to the levels of vaccine coverage, which directly influences the vaccinated individuals as well as the unvaccinated community. Reaching the level of herd protection by increasing vaccine coverage is the basic strategy to eradicate related infectious diseases. Again, herd protection has played an important role in public health practices. With the increasing interests in estimating the vaccine herd protection, we however, have seen only few relevant papers including observational population-based and cluster-randomized clinical trials reported in China. We hope to discuss the study designs for evaluating the vaccine herd protection in order to generate evidence-based related research in this field.
China/epidemiology* ; Communicable Disease Control ; Communicable Diseases/immunology* ; Humans ; Immunity, Herd/immunology* ; Research Design ; Vaccination/trends* ; Vaccines/immunology*

Adjuvants can be defined as pharmacological and immunological components that are able to modify and/or enhance antigen-specific immune responses. Based on the interdisciplinary research between immunology and material science/engineering, various vaccine adjuvant materials have been developed. By rational design and engineering of antigen or adjuvant materials, immune-modulatory vaccine systems generated to activate immune system. Here, we review the current progress of bioengineered prophylactic and/or therapeutic vaccine adjuvant for cancer and/or infectious disease, and discuss the prospect of future vaccine adjuvant materials.
Adjuvants, Immunologic ; Allergy and Immunology ; Communicable Diseases* ; Immune System ; Immunomodulation ; Immunotherapy*