A team at Washington University School of Medicine in St. Louis led by Naresha Saligrama compared T cells from tonsil tissue and from blood. Collaborators included researchers at the University of California, Irvine and other institutions. Their findings appear in the journal Immunity.
The researchers used single-cell sequencing on millions of T cells taken from tonsils and blood. The samples came from donors who had a tonsillectomy, with ages ranging from infants to adults. When they compared cells from the same patients, they found clear differences between tonsil-derived T cells and blood T cells.
The study notes that less than 2% of the body’s total T cells are in blood and that most live in the lymphatic system or in other tissues. Some specialized T cells are found almost only in tissue. The authors say clinicians should consider tissue sites when evaluating vaccine responses and immunotherapies and call for more study of T cells in other tissues.
Difficult words
- tonsil — small tissue at the throat or mouthtonsil tissue
- tonsillectomy — surgical removal of the tonsils
- single-cell sequencing — method to read genetic data from single cells
- T cell — type of immune cell that fights infectionT cells
- lymphatic system — network of vessels and nodes for immune transport
- immunotherapy — treatment that uses the immune system against diseaseimmunotherapies
- donor — person who gives biological samples for researchdonors
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- How might knowing that most T cells live in tissues change how doctors check vaccine responses?
- What challenges can you imagine for collecting tissue samples instead of blood in medical studies?
- Do you think future treatments should focus more on tissue T cells or blood T cells? Why?
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