T cells are one of the important types of white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their cell surface.
Natural killer cells, also known as NK cells or large granular lymphocytes (LGL), are a type of cytotoxic lymphocyte critical to the innate immune system. They belong to the rapidly expanding family of known innate lymphoid cells (ILC) and represent 5–20% of all circulating lymphocytes in humans. The role of NK cells is analogous to that of cytotoxic T cells in the vertebrate adaptive immune response. NK cells provide rapid responses to virus-infected cell and other intracellular pathogens acting at around 3 days after infection, and respond to tumor formation. Most immune cells detect the antigen presented on major histocompatibility complex (MHC) on infected cell surfaces, but NK cells can recognize and kill stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction. They were named "natural killers" because of the notion that they do not require activation to kill cells that are missing "self" markers of MHC class I. This role is especially important because harmful cells that are missing MHC I markers cannot be detected and destroyed by other immune cells, such as T lymphocyte cells.
Polly Celine Eveline Matzinger is a French-born immunologist who proposed the danger model theory of how the immune system works.
The regulatory T cells (Tregs or Treg cells), formerly known as suppressor T cells, are a subpopulation of T cells that modulate the immune system, maintain tolerance to self-antigens, and prevent autoimmune disease. Treg cells are immunosuppressive and generally suppress or downregulate induction and proliferation of effector T cells. Treg cells express the biomarkers CD4, FOXP3, and CD25 and are thought to be derived from the same lineage as naïve CD4+ cells. Because effector T cells also express CD4 and CD25, Treg cells are very difficult to effectively discern from effector CD4+, making them difficult to study. Research has found that the cytokine transforming growth factor beta (TGF-β) is essential for Treg cells to differentiate from naïve CD4+ cells and is important in maintaining Treg cell homeostasis.
Memory T cells are a subset of T lymphocytes that might have some of the same functions as memory B cells. Their lineage is unclear.
Gamma delta T cells are T cells that have a γδ T-cell receptor (TCR) on their surface. Most T cells are αβ T cells with TCR composed of two glycoprotein chains called α (alpha) and β (beta) TCR chains. In contrast, γδ T cells have a TCR that is made up of one γ (gamma) chain and one δ (delta) chain. This group of T cells is usually less common than αβ T cells. Their highest abundance is in the gut mucosa, within a population of lymphocytes known as intraepithelial lymphocytes (IELs).
Mucosal immunology is the study of immune system responses that occur at mucosal membranes of the intestines, the urogenital tract, and the respiratory system. The mucous membranes are in constant contact with microorganisms, food, and inhaled antigens. In healthy states, the mucosal immune system protects the organism against infectious pathogens and maintains a tolerance towards non-harmful commensal microbes and benign environmental substances. Disruption of this balance between tolerance and deprivation of pathogens can lead to pathological conditions such as food allergies, irritable bowel syndrome, susceptibility to infections, and more.
Nicholas P. Restifo is an American immunologist, physician and educator in cancer immunotherapy. Until July 2019, he was a tenured senior investigator in the intramural National Cancer Institute of the National Institutes of Health at Bethesda, Maryland. Nicholas was an executive vice president of research at Lyell based in San Francisco.
Gabrielle T. Belz is an Australian molecular immunologist and viral immunologist. She is a faculty member of the Walter and Eliza Hall Institute of Medical Research, within the Molecular Immunology division. Belz has made important contributions to the understanding of immune system function, especially in relation to the molecular and cellular signalling pathways of immune response to viruses. Her research has focused on understanding the signals that drive the initial development of protective immunity against pathogen infections, such as influenza and herpes viruses. This includes research into how cytotoxic T cells recognise and remove virally-infected cells from the body following infection. Research into the description of the specific factors and response during infection will contribute towards the long-term development of vaccines for infectious disease, and the development of better treatments for autoimmune diseases.
Akiko Iwasaki is a Sterling Professor of Immunobiology and Molecular, Cellular and Developmental Biology at Yale University. She is also a principal investigator at the Howard Hughes Medical Institute. Her research interests include innate immunity, autophagy, inflammasomes, sexually transmitted infections, herpes simplex virus, human papillomavirus, respiratory virus infections, influenza infection, T cell immunity, commensal bacteria, COVID-19 and Long COVID.
Immune checkpoints are regulators of the immune system. These pathways are crucial for self-tolerance, which prevents the immune system from attacking cells indiscriminately. However, some cancers can protect themselves from attack by stimulating immune checkpoint targets.
ILC2 cells, or type 2 innate lymphoid cells are a type of innate lymphoid cell. Not to be confused with the ILC. They are derived from common lymphoid progenitor and belong to the lymphoid lineage. These cells lack antigen specific B or T cell receptor because of the lack of recombination activating gene. ILC2s produce type 2 cytokines and are involved in responses to helminths, allergens, some viruses, such as influenza virus and cancer.
Tissue-resident memory T cells or TRM cells represent a subset of a long-lived memory T cells that occupies epithelial, mucosal and other tissues without recirculating. TRM cells are transcriptionally, phenotypically and functionally distinct from central memory (TCM) and effector memory (TEM) T cells which recirculate between blood, the T cell zones of secondary lymphoid organ, lymph and nonlymphoid tissues. Moreover, TRM cells themself represent a diverse populations because of the specializations for the resident tissues. The main role of TRM cells is to provide superior protection against infection in extralymphoid tissues.
Immunological memory is the ability of the immune system to quickly and specifically recognize an antigen that the body has previously encountered and initiate a corresponding immune response. Generally, they are secondary, tertiary and other subsequent immune responses to the same antigen. The adaptive immune system and antigen-specific receptor generation are responsible for adaptive immune memory.
Weiping Zou is the Charles B. de Nancrede Professor of Pathology, Immunology, Biology, and Surgery at the University of Michigan. He is a scientist noted for his work regarding understanding the nature of human tumor immune responses and developing mechanism-informed combination therapies for cancer. He has developed an international reputation in human tumor immunosuppressive mechanisms in the tumor microenvironment.
Franca Ronchese is an Italian-New Zealand immunologist. She currently leads the immune cell biology programme at the Malaghan Institute of Medical Research in Wellington, New Zealand and is a research professor at Victoria University of Wellington.
Miram Merad is a French-Algerian professor in Cancer immunology and the Director of the Marc and Jennifer Lipschultz Precision Immunology Institute (PrIISM) at the Icahn School of Medicine at Mount Sinai (ISMMS) in New York, NY. She is the corecipient of the 2018 William B. Coley Award for Distinguished Research in Basic Immunology and a member of the United States National Academy of Sciences and the National Academy of Medicine.
Wendy Havran was an American immunologist at the Scripps Research Institute. She specialized in T cells, showing that they are scarce in certain areas of the body.
Thomas S. Kupper is an American physician, academic, and clinician. His work with clinical and research experience spans dermatology, cutaneous oncology, and immunology. He is the Thomas B. Fitzpatrick Professor at Harvard Medical School, and chairs the Departments of Dermatology at Brigham and Women's Hospital. He also leads the Cutaneous Oncology Disease Center at the Dana Farber Cancer Institute.
Roslyn A. Kemp is a New Zealand immunologist, and as of 2023 is a full professor at the University of Otago. Her research focuses on T cells, mucosal and tumour immune responses, inflammation and T cell memory.
