Cells were harvested the next day for flow cytometric analyses. Supernatants were collected and stored at −80°C until analysed by infrared array. Monocyte-derived macrophages were washed at the end of 7 days and replenished with fresh medium. Cells were then either stimulated with hBD-3 or incubated in medium alone overnight.
Culture supernatants were harvested and stored at −80°C until analysed by infrared chemokine array. Cells were harvested with ice-cold PBS and gently scraped. The recovered cells were analysed by flow cytometry. Monocytes were stained with antibodies reactive to CD14, CD80 and CD86. Propidium iodide (PI) was used to assess viability. Propidium iodide (10 μg/ml) was added to cells 10 min before analysis. Pifithrin-�� cell line Cells were examined on an LSRII flow cytometer. Searchlight IR custom Array kits were used for multiplex infrared analyses (Aushon Biosystems, Billerica, MA). Briefly, chemokine capture antibodies were spotted to the bottom of 96-well plates. Fifty microlitres of supernatants or standards were added to 96-well plates and non-bound proteins were washed away after 3 hr incubation at room temperature. Secondary biotinylated detecting antibodies were added and incubated 30 min at room temperature. Plates were washed
and streptavidin-DyLightTM 800 Fluor was added for 30 min at room temperature. Plates were rotated for the duration of incubations. After another wash, plates were R788 supplier centrifuged and scanned with an Odyssey infrared imager and analysed with Searchlight Array software. Non-parametric paired tests were used to assess differences between chemokine concentrations in supernatants from cells that were stimulated compared with cells incubated in medium alone. Mann–Whitney U-tests were used to compare results with cells from HIV+ and HIV− donors. Analyses were performed with spss software (IBM, Armonk,
NY). To assess monocyte responses to hBD-3, LL-37 or Pam3CSK4, we incubated purified monocytes with these various stimuli in overnight cell cultures and subsequently examined induction of co-stimulatory molecule surface 3-oxoacyl-(acyl-carrier-protein) reductase expression by flow cytometric analysis. Human BD-3, and to a modest extent Pam3CSK4, induced CD80 expression in monocytes whereas LL-37 did not affect the expression of this co-stimulatory molecule (Fig. 1a). All three stimuli induced CD86 expression, although hBD-3 provided the most pronounced effects (Fig. 1b). As the intensity of CD86 expression among CD86+ cells appeared to be different depending on the stimuli, we further assessed MFI of CD86+ cells in each experimental condition (medium or medium plus various stimulants). Both hBD-3 and LL-37 tended to increase the intensity of CD86 expression above the levels observed in unstimulated monocytes, whereas Pam3CSK4 did not (Fig. 1b). Hence, co-stimulatory molecule expression is differentially modulated by hBD-3, LL-37 and Pam3CSK4 in human monocytes.