Alexandra Y. Kreins, MD PhD

Clinician Scientist in Paediatric Immunology treating and investigating inborn errors of immunity.

United Kingdom

About

Alexandra is a Group Leader at the UCL Great Ormond Street Institute of Child Health and a Consultant in Paediatric Immunology at Great Ormond Street Hospital, London, UK. She cares for children with inborn errors of immunity, including rare thymic disorders, and has internationally recognised expertise in thymus transplantation for congenital athymia. She holds a Wellcome Trust Career Development Fellowship and leads a translational research programme focused on human thymus biology and T-cell lymphopoiesis. Her work integrates functional organoid models with the study of thymic inborn errors of immunity to generate mechanistic insight and to support the development of future regenerative and thymus function replacement therapies.

Experience

  • UCL Great Ormond Street Institute of Child Health (4 yrs 7 mos)
    • Wellcome Trust Career Development Fellow and Group Leader
      Jan 2026 - Present · 6 mos

      My research programme focuses on developing functional human organoid platforms to model T-lymphopoiesis and thymic stromal function and homeostasis in vitro. By leveraging inborn errors of immunity associated with SCID and athymia, as well as other thymic defects that can be modelled in vitro, we aim to contribute to mechanistic insight into human thymic biology and drive the development of novel thymus function replacement and regenerative therapeutic strategies.

    • Wellcome Trust Clinical Research Career Development Fellow
      Dec 2021 - Jan 2026 · 4 yrs 2 mos

  • Great Ormond Street Hospital for Children NHS Foundation Trust (7 yrs 9 mos)
    • Honorary Consultant in Immunology
      Mar 2023 - Present · 3 yrs 4 mos

      I diagnose and manage children with inborn errors of immunity, including rare thymic defects. This includes the care of patients who may require allogeneic thymus transplantation, a highly specialised therapy that, in Europe, is delivered exclusively at GOSH.

    • Clinical Fellow
      Oct 2018 - Mar 2023 · 4 yrs 6 mos

      Clinical Fellow in Paediatric Immunology, Infectious Diseases and Bone Marrow Transplantation

  • Pediatrician in Training at Kinderspital Zürich
    Oct 2015 - Oct 2018 · 3 yrs 1 mo

    Clinical Paediatrician in training.

  • Clinical Fellow in General Paediatrics, Infectious Diseases and Immunology at Evelina London Children's Hospital
    Aug 2013 - Sep 2015 · 2 yrs 2 mos

  • PhD-student at Weill Cornell Medical College
    Sep 2008 - Jan 2014 · 5 yrs 5 mos

    Doctoral studies in Immunology and Microbial Pathogenesis.