Professor Calman A. MacLennan BA, BM BCh, DPhil, FHEA, FRCP, FRCPath

Professor Calman A. MacLennan

Institute of Immunology and Immunotherapy
Director of BactiVac, the Bacterial Vaccines Network
Professor of Vaccine Immunology

Contact details

Institute of Immunology and Immunotherapy
College of Medical and Dental Sciences
University of Birmingham
B15 2TT

Professor MacLennan is a clinician scientist, vaccinologist, and immunologist, with a career dedicated to end-to-end development of vaccines designed to have global impact in the fight against bacterial disease and the silent pandemic of antimicrobial resistance. This has been achieved through investigating immune mechanisms of protection against infectious diseases, developing vaccines in industry and academia, leading global health vaccine portfolios, and founding and directing the BactiVac global vaccine network.


Professor of Vaccine Immunology:

  • Fellowship of the Royal College of Physicians (FRCP), 2011
  • Fellowship of the Higher Education Academy (FHEA), 2009
  • Fellowship of the Royal College of Pathologists (RCPath), 2008
  • DPhil in Medicine, Green College, University of Oxford, 1997
  • BM, BCh Medicine & Surgery, Green College, University of Oxford, 1992
  • BA, Physiological Sciences, Keble College, University of Oxford, 1989


Calman MacLennan is the Founder and Director of BactiVac, the Bacterial Vaccines Network, and Professor of Vaccine Immunology at the University of Birmingham. He is the Senior Program Officer for Bacterial Vaccines in the Enterics, Diagnostics and Genomic Epidemiology Team, Global Health, at the Bill & Melinda Gates Foundation, where he leads the Shigella and Salmonella vaccines product development portfolios. At the Jenner Institute, University of Oxford, he is a Jenner Investigator and Group Leader, and a Consultant Immunologist at the Oxford University Hospitals NHS Foundation Trust.

A clinician scientist by training, following his medical degree and D.Phil. from the University of Oxford, and during specialist training in clinical immunology, he spent time in Malawi and Kenya investigating immunity to invasive Salmonella disease. He continued this work as a senior clinical fellow at the University of Birmingham, leading to key findings on the importance of antibodies in protective immunity against invasive Salmonella disease, which paved the way for the development of new vaccines against enteric diseases.

From 2010, Professor MacLennan was Head of the Exploratory Programme at the Novartis Vaccines Institute for Global Health, Italy, developing vaccines against Salmonella, Shigella and meningococcus. He returned to the University of Oxford, in 2015, to the Jenner Institute, before moving to the Bill & Melinda Gates Foundation in 2017, and founding the BactiVac Network the same year. His ongoing work at the Jenner Institute focuses on gonorrhoea vaccine development. TYPHIBEV, the Vi-CRM197 typhoid conjugate vaccines that he was involved in inventing, is now a licensed and WHO-prequalified vaccine manufactured by Biological E, India. The vaccine was introduced nationally in Nepal in 2022 and will be introduced in Malawi in 2023.


Ad hoc teaching on Masters’ courses in Immunology and Vaccinology.

Postgraduate supervision

Currently supervising three PhD students.

Other activities

  • Founder & Director of BactiVac, the Bacterial Vaccines Network
  • Vaccine development & mechanisms of immunity to gonorrhoea
  • Vaccine development & mechanisms of immunity to bacterial enteric and diarrhoeal diseases
  • Member of WHO Expert Working Groups for multiple bacterial vaccines: Shigella, Typhoid and Paratyphoid A, invasive nontyphoidal Salmonella and Gonococcal Vaccines
  • Member of WHO Technical Advisory Group on Bacterial Vaccines and AMR
  • Chair of Trial Steering Committee – Wellcome-KEMRI/ PATH Shigella Control Human Infection Model
  • External expert on Wellcome Trust– International Vaccines Institute, Korea, development of a bivalent invasive nontyphoidal Salmonella conjugate vaccine (O:4-DT/O:9-DT)
  • External expert on Wellcome Trust Research Steering Group on WHO/International Vaccines Institute Full Value of Vaccines Assessment for invasive nontyphoidal Salmonella.


MacLennan CA, Stanaway J, Grow S, Vannice S, Steele AD. Salmonella combination vaccines - moving beyond typhoid. Open Forum Infectious Diseases 2023 in press.

MacLennan CA, Grow S, Ma L-F, Steele AD. The Shigella vaccines pipeline. Vaccines 2022;10:1376.

Micoli F, Bjarnarson SP, Arcuri M, Pind AAA, Magnusdottir GJ, Necchi F, Di Benedetto R, Carducci M, Schiavo F, Giannelli C, Pisoni I, Martin LB, Del Giudice G, MacLennan CA, Rappuoli R, Jonsdottir I, Saul A. Short Vi-polysaccharide abrogates T-independent immune response and hyporesponsiveness elicited by long Vi-CRM197 conjugate vaccine. Proc Natl Acad Sci USA 2020 Sep 29;117(39):24443-24449. 

MacLennan CA, Riddle MS, Chen WH, Talaat KR, Jain V, Bourgeois AL, Frenck R, Kotloff K, Porter CK. Consensus Report on Shigella Controlled Human Infection Model: Clinical Endpoints. Clin Infect Dis 2019 Dec 9;69(Supplement_8):S591-S595.

Micoli F, Rondini S, Alfini R, Lanzilao L, Necchi F, Negrea A, Rossi O, Brandt C, Clare S, Mastroeni P, Rappuoli R, Saul A, MacLennan CA. Comparative immunogenicity and efficacy of equivalent outer membrane vesicle and glycoconjugate vaccines against nontyphoidal Salmonella. Proc Natl Acad Sci USA 2018; 115: 10428-33.

MacLennan CA, Msefula CL, Gondwe EN, Gilchrist JJ, Pensulo P, Mandala WL, Mwimaniwa G, Banda M, Kenny J, Wilson LK, Phiri A, MacLennan JM, Molyneux EM. Molyneux ME, Graham SM. Presentation of Life-threatening Invasive Nontyphoidal Salmonella Disease in Malawian Children: A Prospective Observational Study. PLoS Negl Trop Dis 2017; 11: e0006027.

MacLennan CA, Richter A, Hodson J, Faustini S, Birtwistle J, Whitelegg A, Chigiga J, Singo M, Walker-Haywood J, Mulugeta B, Masuka S, Mainey C, Plant T, Drayson MT, Manavi K. Immunization of HIV-infected adults in the UK with Haemophilus influenzae b/meningococcal C glycoconjugate and pneumococcal polysaccharide vaccines. J Acquir Immune Defic Syndr 2016; 73: 287-293.

Hart PJ, O’Shaughnessy CM, Siggins MK, Bobat S, Kingsley RA, Goulding DA, Crump JA, Reyburn H, Micoli F, Dougan G, Cunningham AF, MacLennan CA. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen. PLoS One 2016; 11: e0145945.

Koeberling O, Ispasanie E, Hauser J, Rossi O, Pluschke G, Caugant DA, Saul A, MacLennan CA. A broadly-protective vaccine against meningococcal disease in sub-Saharan Africa based on generalized modules for membrane antigens (GMMA). Vaccine 2014; 32: 2688-95.

Micoli F, Romano MR, Tontini M, Cappelletti E, Gavini M, Proietti D, Rondini S, Swennen E, Santini L, Filippini  S, Balocchi C, Adamo R, Pluschke, Norheim G, Pollard AJ, Saul A, Rappuoli R, MacLennan CA, Berti F, Costantino P. Development of a glycoconjugate vaccine to prevent meningitis in Africa caused by meningococcal serogroup X. Proc Natl Acad Sci USA 2013; 110: 19077-82. 

MacLennan CA, Gilchrist JJ, Gordon MA, Cunningham AF, Cobbold MC, Goodall M, Kingsley RA, Van Oosterhout JJG, Msefula CL, Mandala WL, Leyton DL, Marshall JL, Gondwe EN, Bobat S, López-Macías C, Doffinger R, Henderson IR, Zijlstra EE, Dougan G, Drayson MT, MacLennan ICM, Molyneux ME. Dysregulated humoral immunity to nontyphoidal Salmonella in HIV-infected African adults. Science 2010; 328: 508-512.

MacLennan CA, Gondwe EN, Msefula CL, Kingsley RA, Thomson NR, White SA, Goodall M, Pickard DJ, Graham SM, Dougan GD, Hart CA, Molyneux ME, Drayson MT. The neglected role of antibody in protection against bacteremia caused by nontyphoidal strains of Salmonella in African children. J Clin Inv 2008; 118: 1553-1562.