Alexandre Carmo is Director of the Cell Activation and Gene Expression group at i3S, where he has led pioneering work on the scavenger receptor cysteine-rich (SRCR) superfamily of immune proteins. He graduated in Biochemistry from the University of Lisbon (1987), obtained an MSc in Immunology at the University of Porto (1991) under Maria de Sousa, and completed a DPhil in Molecular Immunology at the University of Oxford (1995) under Alan Williams and Don Mason. His early work provided key insights into T cell activation mechanisms and gene expression regulation. Following a postdoctoral position in Don Mason’s lab at Oxford, he returned to Portugal and launched his own research program on CD5 and CD6 - T cell co-receptors previously believed to be co-stimulatory. His group demonstrated that these molecules are, in fact, negative regulators of T cell activation, shaping immune responses more subtly than initially thought. Later, he expanded his focus to the broader SRCR superfamily, cloning and characterizing multiple members. His work showed that these proteins act as innate immune receptors with antimicrobial and anti-inflammatory properties, including the ability to bind bacteria, viruses, fungi, and protozoa. The transition to i3S in 2015 provided access to state-of-the-art facilities and animal research platforms, enabling in vivo validation of recombinant SRCR proteins with therapeutic potential. This line of research led to the development of a candidate sepsis treatment based on rCD5L, which earned the Born from Knowledge award in 2020. His contributions span over 50 publications, including in high-impact journals such as Nature Methods, EMBO Journal, Cell, Nature Communications, and Nature Immunology, with a recent focus on translational research published in BioDrugs, EBioMedicine, Journal of Biomedical Nanotechnology, and Leukemia. Among his key scientific contributions are: (1) revealing CD6 as a key inhibitory co-receptor that fine-tunes T cell activation thresholds, overturning the prevailing view of it as a co-stimulatory molecule; (2) providing direct experimental evidence that physiological T cell activation is driven by natural ligand-receptor interactions rather than artificial receptor aggregation—an assumption long accepted but rarely tested experimentally; and (3) establishing SRCR proteins as broad-spectrum pattern recognition receptors and immune modulators, capable of recognizing bacteria, fungi, and viruses, with recent findings extending this capacity to include protozoan parasites. As a PI, he has coordinated eleven nationally funded research projects and participated in international consortia, securing over €3 million in research funding. He has mentored 13 postdoctoral fellows/junior researchers, 10 PhD students, and many MSc and undergraduate students. From 2004 to 2015, he directed the GABBA PhD program at the University of Porto, during which more than 140 students completed their doctorates. He has also held academic positions at the Abel Salazar Institute (1998–2015) and Universidade Lusófona (1999–2001).