Nikolaos (Nikos) Papadopoulos (born 1965) is a Greek medical doctor and academic focusing on allergy and immunology. He is a Professor of Allergy and Paediatric Allergy at the University of Athens (NKUA), Greece, where he also leads the Allergy Department of the 2nd Paediatric Clinic. Additionally, he holds the honorary chair on Infection, Immunity, and Respiratory Medicine at the University of Manchester, UK, serves as Professor of Allergy, Immunity and Infection at the Observational and Pragmatic Research Institute (OPRI), Singapore, and is the editor-in-chief of Frontiers in Allergy.
Papadopoulos graduated from Varvakeio Model School in 1982 and entered the medical school of the University of Athens (NKUA) the same year. He completed his medical studies in Guadalajara, Mexico, in 1988, followed by a PhD at NKUA. In 1997, he moved to Southampton, UK, where he worked with Sebastian L. Johnston and Stephen Holgate, focusing his research on the interactions between infections, asthma, and allergy. Upon returning to Greece, he completed his medical training and later started teaching at NKUA.
Papadopoulos has described the mechanisms leading from the common cold to acute asthma, beginning with infection of the bronchial epithelium, followed by local inflammation and a defective antiviral response, and has suggested that repeated infections contribute to persistent allergic inflammation. He has published over 500 scientific papers, and his research has received international awards, including the 2003 Klosterfrau-Group Award for Research of Airway Diseases in Childhood, the European Respiratory Society's Award for Pediatric Respiratory Research in Europe in 2004, the 2010 Phadia Allergy Research Forum (PhARF) Award from the European Academy of Allergy and Clinical Immunology (EAACI), and the Clemens von Pirquet EAACI Medal in 2019.
Over the years, Papadopoulos has led several European research consortia, including PreDicta, CURE, and SynAir-G. He has also been engaged with professional organizations, serving as President of the European Academy of Allergy and Clinical Immunology (EAACI) from 2013 to 2015. His leadership extended to the Respiratory Effectiveness Group (REG), where he acted as President from 2018 to 2020. He has been a member of the Executive Committee of the Global Allergy and Asthma European Network (GALEN) since 2004 and a Board Member of the World Allergy Organization (WAO) since 2023.