PT  - JOURNAL ARTICLE
AU  - Preeti Sharma
AU  - Anjali Vijaykumar
AU  - Jayashree Vijaya Raghavan
AU  - Supriya Rajendra Rananaware
AU  - Alakesh Alakesh
AU  - Janhavi Bodele
AU  - Junaid Ur Rehman
AU  - Shivani Shukla
AU  - Virta Wagde
AU  - Savitha Nadig
AU  - Sveta Chakrabarti
AU  - Sandhya S. Visweswariah
AU  - Dipankar Nandi
AU  - Balasubramanian Gopal
AU  - Siddharth Jhunjhunwala
TI  - Particle Uptake Driven Phagocytosis in Macrophages and Neutrophils Enhances Bacterial Clearance
AID  - 10.1101/2021.08.16.456482
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.08.16.456482
4099  - http://biorxiv.org/content/early/2021/08/16/2021.08.16.456482.short
4100  - http://biorxiv.org/content/early/2021/08/16/2021.08.16.456482.full
AB  - Humans are exposed to numerous synthetic foreign particulates in the form of environmental pollutants and diagnostic or therapeutic agents. Specialized immune cells (phagocytes) clear these particulates by phagocytosing and attempting to degrade them. The process of recognition and internalization of the particulates may trigger changes in the function of phagocytes. Some of these changes, especially the ability of a particle-loaded phagocyte to take up and neutralize pathogens, remains poorly studied. Herein, we demonstrate that the uptake of non-stimulatory cargo-free particles enhances the phagocytic ability of monocytes, macrophages and neutrophils. The enhancement in phagocytic ability was independent of particle properties, such as size or the base material constituting the particle. Additionally, we show that the increased phagocytosis was not a result of cellular activation or cellular heterogeneity but was driven by changes in cell membrane fluidity and cellular compliance. A consequence of the enhanced phagocytic activity was that particulate-laden immune cells neutralize E. coli faster in culture. Moreover, when administered in mice as a prophylactic, particulates enable faster clearance of E. coli and S. epidermidis. Together, we demonstrate that the process of uptake induces cellular changes that favor additional phagocytic events. This study provides insights into using non-stimulatory cargo-free particles to engineer immune cell functions for applications involving faster clearance of phagocytosable particulates.Competing Interest StatementThe authors have declared no competing interest.