ABSTRACT
Objective/background: the development of new tools capable of targeting Mycobacterium tuberculosis [Mtb]-infected cells have potential applications in diagnosis, treatment, and prevention of tuberculosis. In Mtb-infected cells, CD1b molecules present Mtb lipids to the immune system [Mtb lipid-CD1b complexes]. Because of the lack of CD1b polymorphism, specific Mtb lipid-CD1b complexes could be considered as universal Mtb infection markers. 2-Stearoyl-3-hydroxyphthioceranoyl-2' -sulfate-alpha-alpha'-o-trehalose [Ac[2]SGL] is specific for Mtb, and is not present in other mycobacterial species. The CD1b-Ac[2]SGL complexes are expressed on the surface of human cells infected with Mtb. The aim of this study was to generate ligands capable of binding these CD1b-Ac[2]SGL complexes
Methods: a synthetic human scFv phage antibody library was used to select phage-displayed antibody fragments that recognized CD1b-Ac[2]SGL using CD1btransfected THP-1 cells loaded with Ac[2]SGL
Results: one clone, D11- a single, light-variable domain [kappa] antibody [dAb[kappa]11]-showed high relative binding to the Ac[2]SGL-CD1b complex
Conclusion: a ligand recognizing the Ac[2]SGL- CD1b complex was obtained, which is a potential candidate to be further tested for diagnostic and therapeutic applications