From Facebook

Itā€™s Engineerā€™s week, but since I spent 30 of 40 years as a Research Scientistā€¦definitely true.

Mast Cells: Fascinating but Still Elusive after 140 Years from Their Discovery

"After 140 years from their discovery, mast cells remain fascinating but still elusive cells of the immune system.

The characterization of subpopulations of mast cells by single-cell RNA-seq, together with analysis of encoded proteins, will be of paramount importance to modulate the injury- or repair-inducing abilities of these immune cells."

Increased Mast Cell Counts and Degranulation in Microscopic Colitis

"In this study, we report for the first time an elevation in the number of mast cells in Microscopic Colitis (MC) patients.

Mast cell counts have been investigated in association with a variety of GI disorders. Although no consensus regarding baseline mast cell counts and significant increase of mast cell counts had been established, our baseline mast cell counts in control subjects were mostly consistent with those reported in the most comprehensive of these studies [18, 20].

Although the quantitative analysis was performed using correctly oriented sections, mast cell numbers were elevated even in sections cut in the tangential plane.

Furthermore, we observed that MC patients showed higher levels of diffuse extracellular tryptase, a marker of mast cell degranulation, than control subjects.

Taken together, these results suggest that mast cell activation might be involved in the pathogenesis of MC."

Amazing Tech.

Characterization of Mast Cell Activation Syndrome

Lawrence B. Afrin, M.D.,1 Sally Self, M.D.,2 Jeremiah Menk, M.S.,3 and John Lazarchick, M.D.4

A study of 413 patients.

ā€œMast cell activation syndrome (MCAS), a recently recognized non-neoplastic mast cell (MC) disease driving chronic multisystem inflammation Ā± allergy, appears prevalent and thus important. We report the first systematic characterization of a large MCAS population.ā€

"The role of the MC in allergy has long been widely appreciated, but its many critical roles in inflammation, too [e.g., 2], have perhaps emerged ā€œunder the radar.ā€

It is becoming increasingly clear that MCAD (the bulk of which is likely MCAS) is a vast collection of diseases featuring different patterns of both aberrant constitutive MC mediator expression and aberrant MC reactivity.

It also is becoming increasingly clear that MCs may be activated in both immunologic (e.g., immunoglobulin E-mediated) and non-immunologic (e.g., mediated by cytokines such as corticotropin releasing hormone and substance P) manners. "

In a recent study of 143 patients with MCAS, the prevalence of mediators were as shown in the figure.
(From:Am J Med Sci. 2017 Mar; 353(3): 207ā€“215.
Characterization of Mast Cell Activation Syndrome
Lawrence B. Afrin, M.D.,1 Sally Self, M.D.,2 Jeremiah Menk, M.S.,3 and John Lazarchick, M.D.4)

https://www.fda.gov/consumers/consumer-updates/finding-food-allergens-where-they-shouldnt-be

https://anesthesiology.pubs.asahq.org/article.aspx?articleid=1917908

Systemic mastocytosis presenting as intraoperative anaphylaxis with atypical features: a report of two cases

D. E. BRIDGMAN

https://journals.sagepub.com/doi/pdf/10.1177/0310057X1304100120

Mast Cell Degranulation During Abdominal Surgery Initiates Postoperative Ileus in Mice

WOUTER J. DE JONGE

https://www.gastrojournal.org/article/S0016-5085(04)00712-7/pdf

The Role of Mast Cell Stabilization in Treatment of Postoperative Ileus: A Pilot Study

"Although postoperative ileus (POI) is considered multifactorial, intestinal infl ammation resulting from manipulation-induced mast cell activation is recognized as an important pathophysiological mechanism. Therefore, mast cell stabilization may represent a new therapeutic approach to shortening POI.

The aim of this paper was to study the effect of ketotifen, a mast cell stabilizer, on postoperative gastrointestinal transit in patients who underwent abdominal surgery.

In this pilot study, 60 patients undergoing major abdominal surgery for gynecological malignancy with standardized anesthesia were randomized to treatment with ketotifen (4 or 12 mg) or placebo. Patients were treated for 6 days, starting 3 days before surgery.

Gastric emptying of liquids, selected as a primary outcome parameter, was measured 24 h after surgery using scintigraphy. Secondary end points were (scintigraphically assessed) colonic transit, represented as geometrical center of activity (segment 1 (cecum) to 7 (stool)) and clinical parameters. Gastric retention 1 h after liquid intake was signifi cantly reduced by 12 mg (median 3 % (1 ā€“ 7), P = 0.01), but not by 4 mg ketotifen (18 % (3 ā€“ 45), P = 0.6) compared with placebo (16 % (5 ā€“ 75)). Twenty-four hour colonic transit in placebo was 0.8 (0.0 ā€“ 1.1) vs. 1.2 (0.2 ā€“ 1.4) colon segments in the 12 mg ketotifen group ( P = 0.07). Abdominal cramps were signifi cantly relieved in patients treated with 12 mg ketotifen, whereas other clinical parameters were not affected.

CONCLUSIONS: Ketotifen signifi cantly improves gastric emptying after abdominal surgery and warrants further exploration of mast cell stabilizers as putative therapy for POI. "

https://www.researchgate.net/profile/Roel_Bennink/publication/26262378_The_Role_of_Mast_Cell_Stabilization_in_Treatment_of_Postoperative_Ileus_A_Pilot_Study/links/00463536367ab995ff000000/The-Role-of-Mast-Cell-Stabilization-in-Treatment-of-Postoperative-Ileus-A-Pilot-Study.pdf

Critical Role of Protease-activated Receptor 2 Activation by Mast Cell Tryptase in the Development of Postoperative Pain

Sara M. Oliveira, Ph.D.; et. al.

When activated, mast cells release tryptase, which activates protease-activated receptor 2

The role of protease-activated receptor 2 activation in postoperative pain has not been examined

https://anesthesiology.pubs.asahq.org/article.aspx?articleid=2034577

Updated Ro transmission info.