Adapting to survive: How Candida overcomes host-imposed constraints during human colonization

Successful human colonizers such as Candida pathogens have evolved distinct strategies to survive and proliferate within the human host. These include sophisticated mechanisms to evade immune surveillance and adapt to constantly changing host microenvironments where nutrient limitation, pH fluctuations, oxygen deprivation, changes in temperature, or exposure to oxidative, nitrosative, and cationic stresses may occur. Here, we review the current knowledge and recent findings highlighting the remarkable ability of medically important Candida species to overcome a broad range of host-imposed constraints and how this directly affects their physiology and pathogenicity. We also consider the impact of these adaptation mechanisms on immune recognition, biofilm formation, and antifungal drug resistance, as these pathogens often exploit specific host constraints to establish a successful infection. Recent studies of adaptive responses to physiological niches have improved our understanding of the mechanisms established by fungal pathogens to evade the immune system and colonize the host, which may facilitate the design of innovative diagnostic tests and therapeutic approaches for Candida infections.Work at CBMA is supported by the Contrato-Programa UIBD/04050/2020 funded by Portuguese national funds through the FCT I.P. RA and CBA are recipients of FCT PhD fellowships (PD/BD/113813/2015 and PD/BD/135208/2017, respectively). Research stay of RA at KU Leuven was supported by Boehringer Ingelheim Fonds. Work at KU Leuven is supported by grants from the Fund for Scientific Research Flanders (FWO grant nr: G0F8519N) and by the Research Council of the KU Leuven (grant nr: C14/17/063). Work at the University of Exeter is funded by a programme grant from the UK Medical Research Council (MRC) [www.mrc.ac.uk: MR/M026663/1], by the MRC Centre for Medical Mycology, University of Exeter [MR/N006364/1], and by the Wellcome Trust [www.wellcome.ac.uk: 097377]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Simultaneous co-localized super-resolution fluorescence microscopy and atomic force microscopy: combined SIM and AFM platform for the life sciences

Correlating data from different microscopy techniques holds the potential to discover new facets of signaling events in cellular biology. Here we report for the first time a hardware set-up capable of achieving simultaneous co-localized imaging of spatially correlated far-field super-resolution fluorescence microscopy and atomic force microscopy, a feat only obtained until now by fluorescence microscopy set-ups with spatial resolution restricted by the Abbe diffraction limit. We detail system integration and demonstrate system performance using sub-resolution fluorescent beads and applied to a test sample consisting of human bone osteosarcoma epithelial cells, with plasma membrane transporter 1 (MCT1) tagged with an enhanced green fluorescent protein (EGFP) at the N-terminal.Ana I. Gomez Varela wishes to acknowledge support from the Xunta de Galicia, Conselleria de Cultura, Educacion e Ordenacion Universitaria e da Conselleria de Economia, Emprego e Industria (Programa de axudas de apoio a etapa de formacion posdoutoral 2017). Adelaide Miranda and Pieter De Beule acknowledge financial support from Norte's Regional Operational Programme 2014-2020-Norte2020 (NORTE-01-0145-FEDER-000019). Sandra Paiva and Rosana Alves thank Fulbright Commission Portugal and Luso-American Development Foundation (FLAD) for their financial support to perform research work at UC Berkeley, California, USA. We thank the U.S. Embassy in Portugal for supporting David Drubin's visit to Portugal. We thank Ann Fisher of the UC Berkeley Cell Culture Facility for help with cell culture. We thank Dr. Kartoosh Heydari of the Cancer Research Lab Flow Cytometry Core Facility of UC Berkeley. Rosana Alves and Claudia Barata-Antunes are recipients of PhD fellowships from the Portuguese Foundation for Science and Technology (PD/BD/113813/2015 and PD/BD/135208/2017, respectively). The authors want to thank Nikon and Izasa Scientific for their support to the experiment by providing a N SIM-E microscope set-up on loan. We also gratefully acknowledge Dr. Kees van der Oord from Nikon Instruments Europe B.V. for his assistance with the SIM microscope as well as Paulo Madureira and Carlos Pitaes from IZASA Portugal and Jordi Recasens from IZASA Spain for their assistance with the integration of the SIM and AFM microscopes. Finally, we want to thank Benjamin Holmes for fruitful discussions and relentless support