Xerostomia (dry mouth) is frequently experienced by patients treated with radiotherapy for head and neck cancers or with Sjögren's syndrome, with no permanent cure existing for this debilitating condition. To this end, in vitro platforms are needed to test therapies directed at salivary (fluid-secreting) cells. However, since these are highly differentiated secretory cells, the maintenance of their differentiated state while expanding in numbers is challenging. In this study, the efficiency of three reversible thermo-ionically crosslinked gels: (1) alginate-gelatin (AG), (2) collagen-containing AG (AGC), and (3) hyaluronic acid-containing AG (AGHA), to recapitulate a native-like environment for human salivary gland (SG) cell expansion and 3D spheroid formation was compared. Although all gels were of mechanical properties comparable to human SG tissue (~11 kPa) and promoted the formation of 3D spheroids, AGHA gels produced larger (>100 cells/spheroid), viable (>93%), proliferative, and well-organized 3D SG spheroids while spatially and temporally maintaining the high expression of key SG proteins (aquaporin-5, NKCC1, ZO-1, α-amylase) for 14 days in culture. Moreover, the spheroids responded to agonist-induced stimulation by increasing α-amylase secretory granules. Here, we propose alternative low-cost, reproducible, and reversible AG-based 3D hydrogels that allow the facile and rapid retrieval of intact, highly viable 3D-SG spheroids.
Humans ; Hydrogels/chemistry* ; Acinar Cells/cytology* ; Spheroids, Cellular/cytology* ; Salivary Glands/cytology* ; Gelatin/chemistry* ; Collagen/chemistry* ; Alginates/chemistry* ; Cell Culture Techniques/methods* ; Hyaluronic Acid/chemistry* ; Cell Proliferation ; Cell Survival ; Cells, Cultured

OBJECTIVETo establish a simple but effective method of laser scanning confocal microscopic imaging for Ca2+ oscillations of pancreatic acinar cells in adult mice.

METHODSPancreatic acinar cells from adult Kunming mice were isolated acutely with collagenase, and then loaded with fluo-4-AM, a Ca2+ indicator. A laser scanning confocal microscope armed with 488 nm laser was employed to record the dynamic fluorescent signals in-time and synchronously while acetylcholine (ACh) was added in the pancreatic acinar cells.

RESULTS(1) The classic pancreatic acinar cell Ca2+ oscillations were induced by a certain concentration of ACh (100 nmol/L) successfully and steadily, which could be blocked by atropine completely. (2) Plasmic Ca2+ oscillations from different parts of one acinar cell were usually with different amplitudes and almost the same frequencies. But both of amplitudes and frequencies were different among different cells. (3) The acinar cell Ca2+ oscillations were induced by ACh in a concentration-dependent manner.

CONCLUSIONThe laser scanning confocal microscopic imaging for adult mouse pancreatic acinar cell Ca2+ oscillations was established successfully. The features of being easy to use, direct to see lively, high efficiency and good flexibility make it a popular tool for researchers to choose.

Acinar Cells ; chemistry ; Animals ; Calcium ; analysis ; Calcium Signaling ; Cells, Cultured ; Mice ; Microscopy, Confocal ; methods ; Pancreas ; cytology

OBJECTIVETo investigate the expression and relationship of programmed cell death 5 (PDCD5) and cell apoptosis in the parotid gland after leading duct ligation in rat and elucidate the role of PDCD5 on the atophy of parotid gland.

METHODSThe Wistar rat model of leading duct ligation was established, and the samples of parotid gland were obtained from different time point (0, 1, 3, 5, 7, 14, 21, 30, 60, 90 and 120 d). The expression of PDCD5 protein was examined by immunohistochemistry. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL).

RESULTSThe distribution of PDCD5 protein in normal parotid was in cytoplasm with uniformity. The expression of PDCD5 protein was significantly increased and reached the peak at 3 d (1.261 ± 0.048) following main duct ligation. PDCD5 was located both in cytoplasm and nuclear of parotid gland cells. The PDCD5 density in acinar cells was higher than that in duct cells at day 1 and 3 after duct ligation (P < 0.01). The apoptotic cells were obviously upregulated at 3 d after duct ligation. The apoptosis index observed in acinar cells [(21.750 ± 0.119)%] was more than that in duct cells [(5.720 ± 0.205)%]. The difference of apoptosis index between acinar cells and duct cells was statistically significant (P < 0.01). The increased PDCD5 levels were positively correlated with cell apoptosis induced by duct ligation.

CONCLUSIONSThe expression of PDCD5 is associated with the atophy of the parotid gland after rat parotid duct ligation, indicating that PDCD5 might play an important role in apoptotic pathways after parotid duct ligation.

Acinar Cells ; metabolism ; Animals ; Apoptosis ; Apoptosis Regulatory Proteins ; metabolism ; Atrophy ; Cell Nucleus ; metabolism ; Cytoplasm ; metabolism ; Ligation ; Male ; Parotid Gland ; cytology ; metabolism ; pathology ; Rats ; Rats, Wistar ; Salivary Ducts

To study the expression of X-linked inhibitor of apoptosis protein (XIAP) and cell apoptosis in vitro model of acute pancreatitis (AP), we carried out experiments to stimulate AR42J cell line with caerulein (10(-8) mol/L) for 12 hours, then collected cells at various time points (0 h, 4 h, 8 h, 12 h, and 24 h, respectively). We then observed the morphologic changes of AR42J cells with the stimulation of caerulein with electronic microscope. The gene expression of XIAP, caspase-3 and caspase-9 was detected using real-time fluorescence quantitative polymerase chain reaction (FQ-PCR), and the protein expression of XIAP was assessed by western blot. The activation of nuclear factor-kappa B (NF-kappaB) was measured by flow cytometry (FCM). With the stimulation of caerulein, the expression of XIAP and the NF-kappaB activation could first decrease and then increase, but the change of caspase-3 and caspase-9 expressions were opposite. XIAP may inhibit the cell apoptosis in rat pancreatic acinus AR42J cell lines at first with the stimulation of caerulein, then NF-kappaB can upgrade the expression of XIAP and increase the cell apoptosis.
Acinar Cells ; cytology ; metabolism ; Animals ; Apoptosis ; physiology ; Cell Line ; Ceruletide ; pharmacology ; NF-kappa B ; metabolism ; Pancreas ; cytology ; metabolism ; Pancreatitis ; metabolism ; Rats ; X-Linked Inhibitor of Apoptosis Protein ; genetics ; metabolism