Ultrastructural Features of Human Basophil and Mast Cell Secretory Function

Dvorak, Ann M.

doi:10.1016/b978-012473335-0/50007-6

Cited by 13 publications

(18 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, they express ultrastructural features of piecemeal degranulation, a unique pattern of cell secretion previously recognized in MCs infiltrating chronic inflammatory sites or tumurs (Dvorak et al 1973(Dvorak et al , 1974(Dvorak et al , 1976. As piecemeal degranulation is considered a slow, discrete, and long-lasting secretory process (Dvorak 1994(Dvorak , 2000, this finding may suggest a possible, stillundetermined involvement of MCs in some aspects of thymic function during embryonic life. This assumption is further supported by the fact that MCs in the chorioallantoic membrane do not express piecemeal degranulation.…”

Section: Discussionmentioning

confidence: 88%

The thymus is a site of mast cell development in chicken embryos

et al. 2004

View full text Add to dashboard Cite

Thymic mast cells were studied by light and transmission electron microscopy in chicken embryos during organogenesis. Mast cells made their first appearance at day 15. At days 16 and 17, there was a burst of mast cell development with a peak of 278 +/- 54 cells/mm(2) at day 16. Then, mast cell density decreased until hatching. During the whole embryonic period, about 80% of mast cells localized to the thymic medulla. In the cortex, they were less numerous, and some rare mast cells could be identified in the capsule and septa. Thymic mast cells could be recognized in association with hematopoietic foci, but frequently they grew independently from areas of hematopoiesis and appeared as single cells interspersed among thymocytes, thymic epithelial cells, and interdigitating cells. They were often recognized in close relationship with the scanty and delicate extracellular matrix of the developing gland. Viewed by electron microscopy, mast cells were relatively small cells, with a few secretory granules. Exocytosis was never seen, but, notably, granules emptied in a piecemeal degranulation fashion. This study demonstrates that the chicken thymus is a site of mast cell development during embryogenesis. The high mast cell density we found suggests a possible role for these cells during thymus organogenesis.

show abstract

Section: Discussionmentioning

confidence: 88%

The thymus is a site of mast cell development in chicken embryos

et al. 2004

View full text Add to dashboard Cite

show abstract

“…If the rate and amount of vesicular traffic were balanced, granule containers would empty in a "piecemeal" fashion but maintain a constant size. If, on the other hand, the inward flow of endocytotic vesicles exceeded the outward flow of exocytotic vesicles, the granule chambers would become enlarged (Dvorak, 1994).…”

Section: Discussionmentioning

confidence: 99%

Chromaffin granules in the rat adrenal medulla release their secretory content in a particulate fashion

et al. 2004

View full text Add to dashboard Cite

Exocytosis is considered the main route of granule discharge in chromaffin cells. We recently provided ultrastructural evidence suggesting that piecemeal degranulation (PMD) occurs in mouse adrenal chromaffin cells. In the present study, we processed rat adrenal glands for transmission electron microscopy (TEM), and examined chromaffin cells for changes characteristic of PMD. Both adrenaline (A)-and noradrenaline (NA)-storing cells express ultrastructural features suggestive of a slow and particulate mode of granule discharge. In adrenaline-containing cells, some granules present enlarged dimensions accompanied by eroded or dissolved matrices. Likewise, a number of granules in NA-releasing cells show content reduction with variably expanded granule chambers. Dilated, empty granule containers are recognizable in the cytoplasm of both cell types. Characteristically, altered granules and empty containers are seen intermingled with normal, resting granules. In addition, chromaffin granules often show irregular profiles, with budding or tail-like projections of their limiting membranes. Thirty 150-nm-diameter membrane-bound vesicles with a moderately electron-dense or -lucent internal structure are observable in the cytoplasm of both cell types. These vesicles are seen among the granules and some of them are fused with the perigranule membranes in the process of attachment to or budding from the granules. These data add further support to the concept that PMD may be an alternative secretory pathway in adrenal chromaffin cells.

show abstract

“…Recovery from anaphylactic degranulation was recognized by the presence of marked exteriorization of fused granule chambers as surface processes or by the internalization of these processes as canaliculi ( Fig. 1E) (14). Activated MC were scored as being in one of three categories including AND, PMD, or both (15).…”

Section: Numentioning

confidence: 99%

“…MC were divided into three types according to their ultrastructural characteristics; degranulation, rest, and recovery types (13,14). Piecemeal type degranulation (PMD) was defined as the presence of partially or completely empty granule chambers in the absence of intergranular fusion (Fig.…”

Section: Numentioning

confidence: 99%

Activated Mast Cells Infiltrate in Close Proximity to Enteric Nerves in Diarrhea-predominant Irritable Bowel Syndrome

et al. 2003

View full text Add to dashboard Cite

Mast cells (MC) may be one factor influencing the response of visceral afferent nerves to mechanical and chemical stimuli. The aim of this study was to evaluate the degree of infiltration and activity of colonic MC in irritable bowel syndrome (IBS). Biopsy specimens were obtained from the cecum and rectum of 14 diarrhea predominant IBS and 14 normal controls. Electron microscopy was used to determine the number of intact and degranulated colonic MC and to quantify these separately according to the distance between MC and enteric nerves. An increased number of MC in both cecum and rectum in the IBS group in comparison with the control group was demonstrated (p<0.05). Activated MC in close proximity to enteric nerves were significantly increased in both cecum and rectum of the IBS group compared to control group (p<0.005). In addition, activated MC were significantly increased in close proximity to the nerves compared to those in the remote area in both cecum and rectum of the IBS group (p<0.0001). MC were significantly increased and activated in both cecum and rectum of the IBS group compared to controls. MC may play a role in the gut sensory hypersensitivity of IBS.

show abstract

Ultrastructural Features of Human Basophil and Mast Cell Secretory Function

Cited by 13 publications

References 75 publications

The thymus is a site of mast cell development in chicken embryos

The thymus is a site of mast cell development in chicken embryos

Chromaffin granules in the rat adrenal medulla release their secretory content in a particulate fashion

Activated Mast Cells Infiltrate in Close Proximity to Enteric Nerves in Diarrhea-predominant Irritable Bowel Syndrome

Contact Info

Product

Resources

About