Fig. 2: Uptake and elemental composition of intracellular calciprotein particles.
a–d Human freshly isolated blood monocytes were stimulated with 2.5 mM added [Ca2+] in 5.6 mM [Pi] for 30 min, fixed, and embedded for TEM–EDX analysis (n = 2). a STEM HAADF image and higher magnification of the region framed in black; bright areas are electron dense regions. b STEM HAADF imaging of the red framed region in a. c EDX signals for Ca and P. EDX spectra of regions circled in red indicate that bright areas are containing Ca, as indicated by the calcium peaks in the two representative EDX spectra for regions 1 and 4 in b (for spectra from the other marked areas, see Supplementary Fig. 2b). The phosphor signal at 2 keV overlaps with the osmium signal which is found to be in the same region of the spectra. For this reason, both signals are not considered here and the region was excluded during spectra acquisition and mapping of cell samples. d STEM HAADF image of b with EDX signals for Ca and P.
