Background

Studies have suggested that there can be increases in respiratory disease in Europe associated with sandstorms originating from the Sahara, sometimes known as Calima sandstorm events (1, 2). We previously showed that volcanic ash particles increase susceptibility to pneumococcal infection (3).

Aim

Assess effect of as Calima sandstorm particles on pneumococcal adhesion to A549 alveolar epithelial cells in vitro.

Methods

Airborne mineral dust originating in Saharan Africa and deposited on Tenerife during a sandstorm (Calima event, February 2020) were collected.  Samples were filtered (10 mm mesh), suspended in DPBS and added to adherent A549 lung epithelial cells (2x105 cells/well) in cell culture plates for 2h. After washing, D39 S. pneumoniae strain was incubated with cells for 2h. Cells were washed and lysed before adherent bacteria were enumerated on blood agar plates for colony forming units (CFU) counts. PAFR expression assessed by flow cytometry.

Results

Incubation with Calima particles (10mg/ml) increased pneumococcal adhesion to A549 lung epithelial cells (figure, n=6, mean±SEM 1637±/173.8ml vs 2467±252.8/ml, *P<0.05).

Conclusion

Camila Sand particles increases pneumococcal adherence to airway cells in vitro.

References
(1) Karanasiou A et al., Oct 15;47:107-14. doi: 10.1016/j.envint.2012.06.012.

(2) López-Villarrubia E, et al., 2021 Jul;57(7):464-470. doi: 10.1016/j.arbr.2020.03.032.

(3) Miyashita L, et al., ERS 2022 60: 3163; DOI: 10.1183/13993003.congress-2022.3163