Immunotherapy advances最新文献

Vaccination programmes are critically important to suppress the burden of infectious diseases, saving countless lives globally, as emphasised by the current COVID-19 pandemic. Effective adaptive immune responses are complex processes subject to multiple influences. Recent genetic, pre-clinical, and clinical studies have converged to show that availability of iron is a key factor regulating the development of T and B cell responses to infection and immunisation. Lymphocytes obtain iron from circulating transferrin. The amount of iron bound to transferrin is dependent on dietary iron availability and is decreased during inflammation via upregulation of the iron-regulatory hormone, hepcidin. As iron deficiency and chronic inflammatory states are both globally prevalent health problems, the potential impact of low iron availability on immune responses is significant. We describe the evidence supporting the importance of iron in immunity, highlight important unknowns, and discuss how therapeutic interventions to modulate iron availability might be implementable in the context of vaccination and infectious disease.

Human Vγ9/Vδ2 T cells, mucosal-associated invariant T (MAIT) cells, and other unconventional T cells are specialised in detecting microbial metabolic pathway intermediates that are absent in humans. The recognition by such semi-invariant innate-like T cells of compounds like (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP), the penultimate metabolite in the MEP isoprenoid biosynthesis pathway, and intermediates of the riboflavin biosynthesis pathway and their metabolites allows the immune system to rapidly sense pathogen-associated molecular patterns that are shared by a wide range of micro-organisms. Given the essential nature of these metabolic pathways for microbial viability, they have emerged as promising targets for the development of novel antibiotics. Here, we review recent findings that link enzymatic inhibition of microbial metabolism with alterations in the levels of unconventional T cell ligands produced by treated micro-organisms that have given rise to the concept of 'immuno-antibiotics': combining direct antimicrobial activity with an immunotherapeutic effect via modulation of unconventional T cell responses.

During the last two decades, two main schools of modern immunotherapy have come to the forefront. The chimeric anti-CD20 antibody rituximab that was introduced for the treatment of refractory follicular lymphoma in 1998 was one of the first examples of the school of passive immunotherapy. Subsequently major and ever more costly efforts were spent on the development of blockbuster monotherapies including other monoclonal but also bispecific antibodies of highly defined specificity and subclass, antibody-drug conjugates (ADCs), as well as ex vivo expanded tumor-infiltrating lymphocytes, chimeric antigen receptor (CAR)-transduced T cells, and TCR-transduced T cells. On the other hand, there is the school that works toward active induction of patient B- or T-cell immunity against antigens of choice, or active tolerance against pathogenic allergens, auto-antigens or allo-antigens. Stradled in between these two approaches is treatment with blockers of T cell checkpoint control, which releases the brakes of T cells that have already responded to antigen. Extensive and detailed insight into the cellular and molecular interactions that regulate specific immune responses is indispensable in order to be able to optimize efficacy and rule out treatment related toxicity. This applies to all types of immunotherapy. Our knowledge of the checks and balances in the immune system is still increasing at an unprecedented pace, fostering ever more effective and specific (combination) immunotherapies and offering a rich harvest of innovative immunotherapies in the years ahead.

Targeted restoration of immunological tolerance to self-antigens or innocuous environmental allergens represents the ultimate aim of treatment options in autoimmune and allergic disease. Antigen-specific immunotherapy (ASI) is the only intervention that has proven disease-modifying efficacy as evidenced by induction of long-term remission in a number of allergic conditions. Mounting evidence is now indicating that specific targeting of pathogenic T cells in autoinflammatory and autoimmune settings enables effective restoration of immune homeostasis between effector and regulatory cells and alters the immunological course of disease. Here, we discuss the key lessons learned during the development of antigen-specific immunotherapies and how these can be applied to inform future interventions. Armed with this knowledge and current high-throughput technology to track immune cell phenotype and function, it may no longer be a matter of 'if' but 'when' this ultimate aim of targeted tolerance restoration is realised.

Introduction: Ageing is associated with increased number of infections, decreased vaccine efficacy and increased systemic inflammation termed inflammageing. These changes are reflected by reduced recall responses to varicella zoster virus (VZV) challenge in the skin of older adults. Vitamin D deficiency is more common in the old and has been associated with frailty and increased inflammation. In addition, vitamin D increases immunoregulatory mechanisms and therefore has the potential to inhibit inflammageing.

Objectives: We investigated the use of vitamin D₃ replacement to enhance cutaneous antigen-specific immunity in older adults (≥65 years).

Methods: Vitamin D insufficient older adults (n = 18) were administered 6400IU of vitamin D₃/day orally for 14 weeks. Antigen-specific immunity to VZV was assessed by clinical score assessment of the injection site and transcriptional analysis of skin biopsies collected from challenged injection sites pre- and post-vitamin D₃ replacement.

Results: We showed that older adults had reduced VZV-specific cutaneous immune response and increased non-specific inflammation as compared to young. Increased non-specific inflammation observed in the skin of older adults negatively correlated with vitamin D sufficiency. We showed that vitamin D₃ supplementation significantly increased the response to cutaneous VZV antigen challenge in older adults. This enhancement was associated with a reduction in inflammatory monocyte infiltration with a concomitant enhancement of T cell recruitment to the site of antigen challenge in the skin.

Conclusion: Vitamin D₃ replacement can boost antigen-specific immunity in older adults with sub-optimal vitamin D status.