Mast Cell Degranulation Decreases Lipopolysaccharide-Induced Aortic Gene Expression and Systemic Levels of Interleukin-6 In Vivo

Mast cells play an important role in immunomodulation and in the maintenance of vascular integrity. Interleukin-6 (IL-6) is one of the key biomarkers and therapeutic target in systemic vasculitis. The objective of the current study is to describe the role of mast cells in arterial IL-6 homeostasis. Eight- to ten-week-old male C57BL/6 (wild-type) mice were injected with either (a) saline, (b) compound 48/80 (a systemic mast cell degranulating agent), (c) lipopolysaccharide (LPS), or (d) a combination of C48/80 and LPS. Twenty-four hours after the injections, mice were sacrificed and serum samples and aortic tissues were analyzed for determining inflammatory response and cytokine expression profile. The results revealed that induction of mast cell degranulation significantly lowers serum IL-6 levels and aortic expression of IL-6 in LPS-treated mice. Significantly higher aortic expression of toll-like receptor-2 (TLR-2) and TNF-α was seen in the LPS and LPS+C48/80 groups of mice compared to controls. Aortic expression of TLR-4 was significantly decreased in LPS+C48/80 compared to C48/80 alone. LPS+C48/80-treated mice presented with a 3-fold higher aortic expression of suppressor of cytokine signaling (SOCS-1) compared to saline-injected groups. The inhibition of LPS-induced increase in serum IL-6 levels by mast cell degranulation was not seen in H1R knockout mice which suggests that mast cell-derived histamine acting through H1R may participate in the regulatory process. To examine whether the mast cell-mediated downregulation of LPS-induced IL-6 production is transient or cumulative in nature, wild-type mice were injected serially over a period of 10 days (5 injections) and serum cytokine levels were quantified. We found no significant differences in serum IL-6 levels between any of the groups. While mice injected with C48/80 or LPS had higher IL-10 compared to vehicle-injected mice, there was no difference between C48/80- and LPS+C48/80-injected mice. In conclusion, in an in vivo setting, mast cells appear to partially and transiently regulate systemic IL-6 homeostasis. This effect may be regulated through increased systemic IL-10 and/or aortic overexpression of SOCS-1.

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Mast cell activation is not required for induction of airway hyperresponsiveness by ozone in mice

Journal of Applied Physiology ◽

10.1152/jappl.1999.86.1.202 ◽

1999 ◽

Vol 86 (1) ◽

pp. 202-210 ◽

Cited By ~ 14

Author(s):

N. Noviski ◽

J. P. Brewer ◽

W. A. Skornik ◽

S. J. Galli ◽

J. M. Drazen ◽

...

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Airway Hyperresponsiveness ◽

Essential Role ◽

Cell Activation ◽

Mast Cell Degranulation ◽

Mast Cell Activation ◽

Polymorphonuclear Cell ◽

Pulmonary Parenchyma

Exposure to ambient ozone (O3) is associated with increased exacerbations of asthma. We sought to determine whether mast cell degranulation is induced by in vivo exposure to O3in mice and whether mast cells play an essential role in the development of pulmonary pathophysiological alterations induced by O3. For this we exposed mast cell-deficient WBB6F1- kitW/ kitW-v( kitW/ kitW-v) mice and the congenic normal WBB6F1(+/+) mice to air or to 1 or 3 parts/million O3for 4 h and studied them at different intervals from 4 to 72 h later. We found evidence of O3-induced cutaneous, as well as bronchial, mast cell degranulation. Polymorphonuclear cell influx into the pulmonary parenchyma was observed after exposure to 1 part/milllion O3only in mice that possessed mast cells. Airway hyperresponsiveness to intravenous methacholine measured in vivo under pentobarbital anesthesia was observed in both kitW/ kitW-vand +/+ mice after exposure to O3. Thus, although mast cells are activated in vivo by O3and participate in O3-induced polymorphonuclear cell infiltration into the pulmonary parenchyma, they do not participate detectably in the development of O3-induced airway hyperresponsiveness in mice.

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Thrombopoietin Regulates Proliferation and Maturation of Murine Mast Cells.

Blood ◽

10.1182/blood.v104.11.1707.1707 ◽

2004 ◽

Vol 104 (11) ◽

pp. 1707-1707

Author(s):

Giovanni Migliaccio ◽

Barbara Ghinassi ◽

Lucia Centurione ◽

Maria Zingariello ◽

Lucia Bianchi ◽

...

Keyword(s):

Bone Marrow ◽

Mast Cell ◽

Cell Differentiation ◽

Growth Factor ◽

Mast Cells ◽

Wild Type ◽

Connective Tissues ◽

Immature Cells

Abstract Megakaryocytopoiesis is regulated by extrinsic (interaction of the growth factor thrombopoietin, TPO with its receptor Mpl) and intrinsic (interaction between the trascription factors GATA-1 and Fog-1) factors. The observation that mice impaired for GATA-1 expression (i.e. harbouring the GATA-1low mutation) are defective not only in megakaryocyte maturation but also in mast cell differentiation (Migliaccio et al. J Exp Med197:281, 2003), led us to investigate whether TPO might control mast cell differentiation as well. We first observed that mice genetically unable to responde to TPO (Mplnull mice) express in the connective tissues 5 times more mast cells than their normal littermates. Then, we analysed the effects on mast cell differentiation of in vivo treatment with TPO. Normal mice, and their GATA-1low littermates, were injected i.p. with TPO (100 μg/kg/day per 5 days, kindly provided by Kirin Brewery, Japan) and the number of immature (Toluidinepos) and mature (AlcianBlue/Saphraninepos) mast cells present in the connective tissues of the animals, as well as the frequency of GATA-1pos and TUNELpos mast cells, was evaluated 14 days after treatment. In wild-type animals, TPO reduced the presence of GATA-1 in mast cells (by immuno-histochemistry) and increased the number of immature cells (from 320±28 to 852±60) and of those undergoing apoptosis (from 16±1 to 600±43). In contrast, in GATA-1low animals, TPO-treatment induced the expression of GATA-1 in mast cells while decreased the number of immature cells (from 1100±72 to 427±29) as well as that of apoptotic cells (from 600±45 to 60±2). The role of TPO on mast cell differentiation were further confirmed by the analysis of the effects exerted by the growth factor on in vitro differentiation of bone marrow derived mast cells (BMMC). In these experiments, wild type bone marrow and spleen cells were cultured for 21 days with SCF and IL-3 with or without TPO and BMMC differentiation measured on the basis of the number of cells expressing the phenotype c-kithigh/CD34high and FcεRIpos. In cultures stimulated with SCF and IL-3, all the cells expressed the phenotype c-kithigh/CD34high and FcεRIpos. In contrast, in cultures supplemented also with SCF, IL-3 and TPO, only 25% of the cells were c-kithigh/CD34high and none of them was FcεRIpos. These results establish a role for TPO in the control of mast cell differentiation (possibly by modulating the GATA-1 content of the cells) and unveil further similarities between the mechanism(s) controlling megakaryocyte and mast cell differentiation.

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Glaucocalyxin A Attenuates Allergic Responses by Inhibiting Mast Cell Degranulation through p38MAPK/NrF2/HO-1 and HMGB1/TLR4/NF-κB Signaling Pathways

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/6644751 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Yihua Piao ◽

Jingzhi Jiang ◽

Zhiguang Wang ◽

Chongyang Wang ◽

Shan Jin ◽

...

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Signaling Pathway ◽

Nuclear Translocation ◽

Calcium Influx ◽

Mast Cell Degranulation ◽

Therapeutic Drug ◽

High Mobility Group Protein

Glaucocalyxin A (GLA) has various pharmacological effects like antioxidation, immune regulation, and antiatherosclerosis. Here, in this study, the effect and mechanism of GLA on mast cell degranulation were studied. The results of the anti-DNP IgE-mediated passive cutaneous anaphylaxis (PCA) showed that GLA dramatically inhibited PCA in vivo, as evidenced by reduced Evans blue extravasation and decreased ear thickness. In addition, GLA significantly reduced the release of histamine and β-hexosaminidase, calcium influx, cytokine (IL-4, TNF-α, IL-1β, IL-13, and IL-8) production in the RBL-2H3 (rat basophilic leukemia cells), and RPMCs (peritoneal mast cells) in vitro. Moreover, we further investigated the regulatory mechanism of GLA on antigen-induced mast cells by Western blot, which showed that GLA inhibited FcεRI-mediated signal transduction and invalidated the phosphorylation of Syk, Fyn, Lyn, Gab2, and PLC-γ1. In addition, GLA inhibited the recombinant mouse high mobility group protein B1- (HMGB1-) induced mast cell degranulation through limiting nuclear translocation of NF-κBp65. Treatment of mast cells with siRNA-HMGB1 significantly inhibited HMGB1 levels, as well as MyD88 and TLR4, decreased intracellular calcium levels, and suppressed the release of β-hexosaminidase. Meanwhile, GLA increased NrF2 and HO-1 levels by activating p38MAPK phosphorylation. Consequently, these data suggest that GLA regulates the NrF2/HO-1 signaling pathway through p38MAPK phosphorylation and inhibits HMGB1/TLR4/NF-κB signaling pathway to reduce mast cell degranulation and allergic inflammation. Our findings could be used as a promising therapeutic drug against allergic inflammatory disease.

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Inosine-induced vasoconstriction is mediated by histamine and thromboxane derived from mast cells

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1996.270.2.h560 ◽

1996 ◽

Vol 270 (2) ◽

pp. H560-H566 ◽

Cited By ~ 4

Author(s):

R. K. Shepherd ◽

B. R. Duling

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Ruthenium Red ◽

Mast Cell Degranulation ◽

Cheek Pouch ◽

Hamster Cheek Pouch ◽

Cell Staining ◽

Subsequent Response ◽

Cheek Pouches

Mast cell degranulation has been shown to release products that cause arteriolar constriction. We previously reported that two nucleosides, adenosine and inosine, cause vasoconstriction of isolated hamster cheek pouch arterioles by stimulating degranulation of periarteriolar mast cells. The objectives of the present study were to characterize the nucleoside-dependent vasoconstriction in vivo and to determine the mediator or mediators responsible. We examined the vasomotor effect of inosine on arterioles in the cheek pouches of anesthetized hamsters (70 mg/kg pentobarbital sodium) in the control situation and in the presence of receptor antagonists for histamine (H1), thromboxane A2 (Tx), and leukotrienes (LT). Most experiments were carried out using inosine applied once locally via micropipette to arterioles and observing the subsequent response. Over a range of inosine concentrations from 10(-5) to 10(-3) M in the pipette, we observed a dose-dependent increase in the incidence and magnitude of constriction. In addition, mast cell staining with ruthenium red was observed after stimulation with inosine, an indication of mast cell degranulation. Neither the H1, Tx, nor LT antagonist alone had a significant effect on the vasomotor response to inosine. However, combined H1 and Tx blockade significantly reduced the incidence and magnitude of inosine-induced constriction. These data establish that inosine-induced constriction occurs in vivo and support the role of mast cells in this response. Furthermore they suggest that multiple mediators, primarily histamine and thromboxane, are responsible for the observed constriction.

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The BH3-only protein Puma plays an essential role in cytokine deprivation–induced apoptosis of mast cells

Blood ◽

10.1182/blood-2007-02-073957 ◽

2007 ◽

Vol 110 (9) ◽

pp. 3209-3217 ◽

Cited By ~ 83

Author(s):

Maria Ekoff ◽

Thomas Kaufmann ◽

Maria Engström ◽

Noboru Motoyama ◽

Andreas Villunger ◽

...

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Essential Role ◽

Wild Type ◽

Cell Numbers ◽

Growth Factor Deprivation ◽

Induced Apoptosis ◽

Cytokine Deprivation

Abstract Mast cells play critical roles in the regulation of inflammation. One characteristic feature of mast cells is their relatively long lifespan in vivo. Members of the Bcl-2 protein family are regulators of cell survival and apoptosis, where the BH3-only proteins are critical proapoptotic proteins. In this study we investigated the role of the BH3-only proteins Noxa, Bad, Bim, Bmf, Bid, and Puma in apoptosis of mucosal-like mast cells (MLMCs) and connective tissue–like mast cells (CTLMCs). We demonstrate that Puma is critical for the induction of mast-cell death following cytokine deprivation and treatment with the DNA-damaging agent etoposide in MLMCs and CTLMCs. Using p53−/− mast cells, we found that cytokine deprivation–induced apoptosis, in contrast to that elicited by etoposide, is p53-independent. Interestingly, mast cells deficient in FOXO3a, previously proposed as a transcription factor for Puma induction in response to growth factor deprivation, were markedly resistant to cytokine withdrawal compared with wild-type cells. Moreover, overexpression of phosphorylation-deficient, constitutively active FOXO3a caused an up-regulation of Puma. In conclusion, our data demonstrate a pivotal role for Puma in the regulation of cytokine deprivation–induced mast-cell apoptosis and suggest a plausible role for Puma in the regulation of mast cell numbers in vivo.

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Loss of Pak1 Corrects Multiple Gain of Function Phenotypes in Nf1+/− Mast Cells.

Blood ◽

10.1182/blood.v110.11.236.236 ◽

2007 ◽

Vol 110 (11) ◽

pp. 236-236

Author(s):

Andrew McDaniel ◽

D. Wade Clapp ◽

J. Chernoff

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Tumor Suppressor ◽

Tumor Progression ◽

Mapk Pathway ◽

Mapk Signaling ◽

Conditional Knockout ◽

Wild Type ◽

Cell Functions

Abstract Neurofibromatosis type 1, caused by mutations in the tumor suppressor gene NF1, is the most common genetic disorder in man and is characterized by the development of tumors called neurofibromas. Studies in genetically engineered Nf1 knockout mice have demonstrated that loss of the Nf1 tumor suppressor in Schwann cells, the known tumorigenic cell in neurofibromas, is necessary but not sufficient for tumor formation. By using adoptive transfer, we have now established that haploinsufficiency of Nf1 in the hematopoietic microenvironment (specifically mast cells) is necessary and sufficient for tumor progression in a Nf1 conditional knockout model. It is known that mast cells promote tumor progression via the secretion of growth factors and proteinases. Thus molecules that target mast cell function may be useful therapeutically. We have previously demonstrated that haploinsufficiency of Nf1 results in hyperproliferation and hyperactivation of the mitogen-activated protein kinase (MAPK) pathway in bone marrow-derived mast cells in response to kit-ligand (kit-L). Cross-cascade signaling between phosphoinositide 3-kinase activated Rho-GTPases and the classical MAPK pathway has been shown to be responsible for these abnormal phenotypes. p21-activated kinases (Paks) are downstream mediators of Rho-GTPase proteins that have been implicated in immortalized cells as positive regulators of MAPK pathway members and as modulators of cell growth and cytoskeletal dynamics. Utilizing an intercross of Pak 1−/− mice with Nf1+/− mice, we studied how Pak1 in regulates cellular functions associated with haploinsufficiency at Nf1 in primary mast cells. Loss of Pak1 corrects the gains of function in proliferation and migration found in Nf1+/− mast cells back to wild type levels via differential regulation of MAPKs. Pak1 regulates proliferation via a Pak/Erk pathway, while a Pak1/p38 pathway is critical for migration. The increased release of preformed inflammatory mediators in Nf1 haploinsufficient mast cells was also abrogated by genetic disruption of Pak1. Pak1 was found to contribute to MAPK signaling by modulating both ERK and p38 activation. Loss of Pak1 reduces the hyperactivation of ERK and p38 found in Nf1+/− mast cells to that of wild type controls. Further, using a model that stimulates local proliferation of mast cells in vivo, we confirm that loss of Pak1 corrects the accumulation and degranulation of Nf1+/− mast cells in vivo to wild type levels. Thus, Pak1 is a novel mediator of Ras-dependent mast cell functions, and treatments that target Pak1 may be useful as a targeted therapy for treatment of neurofibromas.

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Intraperitoneal influx of neutrophils in response to IL-33 is mast cell–dependent

Blood ◽

10.1182/blood-2012-05-434209 ◽

2013 ◽

Vol 121 (3) ◽

pp. 530-536 ◽

Cited By ~ 59

Author(s):

Mattias Enoksson ◽

Christine Möller-Westerberg ◽

Grzegorz Wicher ◽

Padraic G. Fallon ◽

Karin Forsberg-Nilsson ◽

...

Keyword(s):

Bone Marrow ◽

Mast Cell ◽

Mast Cells ◽

Inflammatory Responses ◽

Neutrophil Infiltration ◽

Cell Types ◽

Wild Type ◽

Inflammatory Reactions ◽

Neutrophil Response

Abstract IL-33 is a recently discovered cytokine involved in induction of Th2 responses and functions as an alarmin. Despite numerous recent studies targeting IL-33, its role in vivo is incompletely understood. Here we investigated inflammatory responses to intraperitoneal IL-33 injections in wild-type and mast cell–deficient mice. We found that wild-type mice, but not mast cell–deficient Wsh/Wsh mice, respond to IL-33 treatment with neutrophil infiltration to the peritoneum, whereas other investigated cell types remained unchanged. In Wsh/Wsh mice, the IL-33–induced innate neutrophil response could be rescued by local reconstitution with wild-type but not with T1/ST2−/− mast cells, demonstrating a mast cell–dependent mechanism. Furthermore, we found this mechanism to be partially dependent on mast cell–derived TNF, as we observed reduced neutrophil infiltration in Wsh/Wsh mice reconstituted with TNF−/− bone marrow–derived mast cells compared with those reconstituted with wild-type bone marrow–derived mast cells. In agreement with our in vivo findings, we demonstrate that humanneutrophils migrate toward the supernatant of IL-33–treated human mast cells. Taken together, our findings reveal that IL-33 activates mast cells in vivo to recruit neutrophils, a mechanism dependent on IL-33R expression on peritoneal mast cells. Mast cells activated in vivo by IL-33 probably play an important role in inflammatory reactions.

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Evidence that vitamin D3 promotes mast cell–dependent reduction of chronic UVB-induced skin pathology in mice

Journal of Experimental Medicine ◽

10.1084/jem.20091725 ◽

2010 ◽

Vol 207 (3) ◽

pp. 455-463 ◽

Cited By ~ 72

Author(s):

Lisa Biggs ◽

Chunping Yu ◽

Boris Fedoric ◽

Angel F. Lopez ◽

Stephen J. Galli ◽

...

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Low Dose ◽

Interleukin 10 ◽

Wild Type ◽

Epidermal Hyperplasia ◽

Dihydroxyvitamin D3 ◽

Uvb Irradiation

Mast cell production of interleukin-10 (IL-10) can limit the skin pathology induced by chronic low-dose ultraviolet (UV)-B irradiation. Although the mechanism that promotes mast cell IL-10 production in this setting is unknown, exposure of the skin to UVB irradiation induces increased production of the immune modifying agent 1α,25-dihydroxyvitamin D3 (1α,25[OH]2D3). We now show that 1α,25(OH)2D3 can up-regulate IL-10 mRNA expression and induce IL-10 secretion in mouse mast cells in vitro. To investigate the roles of 1α,25(OH)2D3 and mast cell vitamin D receptor (VDR) expression in chronically UVB-irradiated skin in vivo, we engrafted the skin of genetically mast cell–deficient WBB6F1-KitW/W-v mice with bone marrow–derived cultured mast cells derived from C57BL/6 wild-type or VDR−/− mice. Optimal mast cell–dependent suppression of the inflammation, local production of proinflammatory cytokines, epidermal hyperplasia, and epidermal ulceration associated with chronic UVB irradiation of the skin in KitW/W-v mice required expression of VDR by the adoptively transferred mast cells. Our findings suggest that 1α,25(OH)2D3/VDR-dependent induction of IL-10 production by cutaneous mast cells can contribute to the mast cell’s ability to suppress inflammation and skin pathology at sites of chronic UVB irradiation.

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Histamine, mast cells and ovarian function

Journal of Endocrinology ◽

10.1677/joe.0.1200363 ◽

1989 ◽

Vol 120 (3) ◽

pp. 363-371 ◽

Cited By ~ 32

Author(s):

A. Krishna ◽

K. Beesley ◽

P. F. Terranova

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Ovarian Function ◽

Cell Types ◽

Mast Cell Degranulation ◽

Future Research ◽

Corpora Lutea ◽

Theca Externa

ABSTRACT Mast cells, endothelial cells, basophils and platelets are potential sources of histamine in the ovary. Little is known about the role of the latter three cell types in ovarian function. Several studies have revealed changes in the number and degranulation (release of histamine) of mast cells in the ovary during the cycle. Mast cells degranulate on pro-oestrus in the rodent ovary, and mast cells numbers increase in the theca externa of the dominant follicle in the bovine ovary. In rodents, mast cells are limited to the ovarian hilum and are not observed in follicles, corpora lutea and interstitium; this contrasts with larger species such as man, cows and monkeys where mast cells are observed throughout the ovary. Evidence is accumulating that mast cell degranulation in the ovary may be regulated by neuronal input. Neurones have been shown to have close morphological relationships with mast cells in the ovary. Histamine participates in regulating capillary permeability and blood flow in the ovary. These actions are induced by injections of LH, yet the mechanism by which LH induces mast cell degranulation is unknown. Histamine stimulates ovarian contractility, ovulation and follicular progesterone secretion in vitro. Whether these actions of histamine occur in vivo are currently unknown. This review gives a chronological description of the discoveries of the effects of histamine on ovarian function and makes suggestions for future research in this area. Journal of Endocrinology (1989) 120, 363–371

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Platelet and Erythrocyte Extravasation across Inflamed Corneal Venules Depend on CD18, Neutrophils and Mast Cell Degranulation

International Journal of Molecular Sciences ◽

10.3390/ijms22147360 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7360

Author(s):

Angie De La Cruz ◽

Aubrey Hargrave ◽

Sri Magadi ◽

Justin A. Courson ◽

Paul T. Landry ◽

...

Keyword(s):

Mast Cell ◽

Cell Types ◽

Mast Cell Degranulation ◽

Wild Type ◽

Delayed Wound Healing ◽

Corneal Epithelial ◽

Corneal Abrasion ◽

Low Levels ◽

Endothelial Pores

Platelet extravasation during inflammation is under-appreciated. In wild-type (WT) mice, a central corneal epithelial abrasion initiates neutrophil (PMN) and platelet extravasation from peripheral limbal venules. The same injury in mice expressing low levels of the β2-integrin, CD18 (CD18hypo mice) shows reduced platelet extravasation with PMN extravasation apparently unaffected. To better define the role of CD18 on platelet extravasation, we focused on two relevant cell types expressing CD18: PMNs and mast cells. Following corneal abrasion in WT mice, we observed not only extravasated PMNs and platelets but also extravasated erythrocytes (RBCs). Ultrastructural observations of engorged limbal venules showed platelets and RBCs passing through endothelial pores. In contrast, injured CD18hypo mice showed significantly less venule engorgement and markedly reduced platelet and RBC extravasation; mast cell degranulation was also reduced compared to WT mice. Corneal abrasion in mast cell-deficient (KitW-sh/W-sh) mice showed less venule engorgement, delayed PMN extravasation, reduced platelet and RBC extravasation and delayed wound healing compared to WT mice. Finally, antibody-induced depletion of circulating PMNs prior to corneal abrasion reduced mast cell degranulation, venule engorgement, and extravasation of PMNs, platelets, and RBCs. In summary, in the injured cornea, platelet and RBC extravasation depends on CD18, PMNs, and mast cell degranulation.

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