Ian Calman Muir MacLennan

{{Short description|British immunologist}}

{{Use dmy dates|date=April 2022}}

{{Infobox scientist

|name = Ian Calman Muir MacLennan

|image =

|birth_date = {{Birth date and age|1939|12|30|df=y}}

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|field = Immunology

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|work_institution = University of Birmingham

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|known_for = contributions to immunology
discovered marginal zone B-cells

|prizes = FRS (2012)

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Ian Calman Muir MacLennan, CBE, FRS, is Emeritus Professor of Immunology at the University of Birmingham MRC Centre for Immune Regulation in Birmingham, UK.

He was born on 30 December 1939.{{cite book|editor1-last=Bott|editor1-first=Simon|title=Who's Who of British Scientists 1980/81|date=1980|publisher=Simon Books Limited|isbn=9780862290016|page=317|edition=3rd}} He has made pioneering contributions to immunology and was the first to discover marginal zone B-cells.

He was made a Commander of the Order of the British Empire in the Queen's Birthday Honours in 2005.{{Citation|title=Queen's Birthday Honours List|magazine=The Times Higher Education|date=17 June 2005|url=http://www.timeshighereducation.co.uk/news/queens-birthday-honours-list/196741.article|access-date=4 May 2015}} He was elected a Fellow of the Royal Society (FRS) in 2012, his nomination reads:{{centered pull quote|Ian MacLennan has made several landmark contributions to immunology and especially our understanding of antibody production. His classic experiments led him propose a role for germinal centres in affinity maturation of antibody responses by a process of hypermutation followed by antigen-mediated selection. Subsequently, he identified the basis of the multi-step selection process that protects against autoantibody production. He also first discovered marginal zone B cells and identified how they counter encapsulated bacterial infection. His early work revealed and characterized the cells now termed NK cells and their capacity to kill antibody-coated nucleated cells.}}{{cite web|title=Professor Ian Calman Muir MacLennan CBE FMedSci FRS|url=https://royalsociety.org/people/fellowship/2012/ian-maclennan/|publisher=The Royal Society|access-date=4 May 2015}}