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Isolation of Salivary Epithelial Cells from Human Salivary Glands for In Vitro Growth as Salispheres or Monolayers
Published on: July 15, 2019
Cyclic AMP-receptor proteins in human salivary glands.
M Piludu1, M I Mednieks, A R Hand
1Departimento di Citomorfologia, Università Degli Studi di Cagliari, Cagliari, Italy.
European Journal of Morphology
|October 21, 2003
Summary
Cyclic AMP receptor proteins (cARP) are found in human salivary glands, primarily in serous cells of the parotid and submandibular glands. This study reveals species differences in cARP distribution within salivary glands.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Cyclic AMP receptor proteins (cARP) are regulatory subunits of cyclic AMP-dependent protein kinase (PKA).
- cARP, an isoform of the PKA type II R subunit (RII), is a polyfunctional protein found in most mammalian tissues.
- cARP is expressed in rodent salivary glands and secreted into saliva, but its expression in human salivary glands is less understood.
Purpose of the Study:
- To investigate the expression and cellular localization of cARP in human salivary glands.
- To compare the distribution of cARP in human salivary glands with that observed in rodent species.
- To explore the potential role of cARP in salivary gland function and regulation.
Main Methods:
- Immunoelectron microscopy was employed to detect cARP in human salivary gland tissue.
- Thin sections of salivary glands were labeled with anti-cARP primary antibody and gold-conjugated secondary antibody.
- Quantitative analysis was performed to assess the variability and distribution of cARP labeling.
Main Results:
- cARP labeling was observed in the secretory granules and cytoplasm of serous cells in parotid, submandibular (SMG), and sublingual glands.
- Unlike rodents, intercalated and striated duct cells in human glands also showed cARP labeling in their granules.
- Mucous cells exhibited moderate cARP reactivity in the Golgi complex and filamentous bodies, but not in cytoplasm or granules; mitochondria and nuclei were unlabeled.
Conclusions:
- Serous cells of the parotid and SMG are the primary sources of salivary cARP in humans.
- Significant species differences exist in the glandular distribution of RII (cARP).
- The tissue and cellular distribution of RII may serve as an indicator for regulating gene expression and cell differentiation.
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