Experimental and Molecular Pathology 96 (2014) 230–234
Contents lists available at ScienceDirect
Experimental and Molecular Pathology journal homepage: www.elsevier.com/locate/yexmp
Do mast cells play a pathogenetic role in neurofibromatosis type 1 and ulcerative colitis? Felicita Baratelli a,⁎, Mary Le a, George B. Gershman b, Samuel W. French a a b
Harbor–UCLA Medical Center, Department of Pathology, 1000 West Carson, Torrance, 90502 CA, United States Division of Gastroenterology, 1000 West Carson, Torrance 90502, CA, United States
a r t i c l e
i n f o
Article history: Received 11 February 2014 Available online 26 February 2014 Keywords: Mast cell Neurofibromatosis type 1 Ulcerative colitis Inflammatory bowel disease
a b s t r a c t Concurrent association of neurofibromatosis type I and ulcerative colitis has been reported in one clinical case (Tavakkoli et al., 2009). Although this association may represent a casual finding, a common pathophysiology is postulated. Mast cells have been implicated in the pathogenesis of both neurofibromatosis type 1 and ulcerative colitis (He, 2004; Yoshida et al., 2010). Mast cells are typically present in neurofibromas microenvironment where they appear to contribute to tumor initiation, progression and angiogenesis (Staser et al., 2010, 2013). Moreover, interaction of mast cells with nerves throughout the gastrointestinal tract has been correlated with progression and maintenance of ulcerative colitis (Stoyanova and Gulubova, 2002). We describe a 14 year-old male with history of neurofibromatosis type 1 and new onset of ulcerative colitis diagnosed on clinical and histological findings. On gross examination the entire colonic mucosa appeared edematous showing a peculiar granular pattern, with focal erythema, shallow ulcers and multiple sessile polyps. Hematoxylin and eosin stained tissue biopsies from the colonic mucosa showed chronic inflammatory bowel disease, severe activity, consistent with chronic ulcerative colitis. Immunohistochemistry stain of the intestinal lesions revealed high expression of Neuron Specific Enolase (NSE) and S100 highlighting the presence of a Schwann cell component. In addition, c-kit/CD117 positive stain indicated a marked increase of mast cells in the lamina propria. This pattern of cellularity in the lamina propria showing increased mast cells and augmented Schwann cell component was absent in the colonic mucosa of a normal control or a patient with ulcerative colitis alone. Our observation supports the evidence of a pathogenetic role of the mast cell in ulcerative colitis associated with neurofibromatosis type 1. Further investigations are warranted to confirm the significance of this correlation as it may impact therapeutic approaches of these pathologies. © 2014 Elsevier Inc. All rights reserved.
Introduction
Case report
Concomitant association of histologically proven ulcerative colitis (UC) and neurofibromatosis (NF) type 1 is a rare finding documented in one adult clinical case by Tavakkoli et al. (1) Previous literature identified mast cells as important elements involved in both pathogenesis of inflammatory bowel disease and development of neurofibromas (2, 3). Here we report a pediatric case of newly diagnosed UC in NF type 1. We evaluated the presence of mast cells and Schwann cells in the colon tissue biopsy diagnosed with UC by immunohistochemistry (IHC). Mast cells were identified by expression of CD117/c-kit, and Schwann cells by expression of Neuron Specific Enolase (NSE) and S100. As control tissue, we utilized a colon biopsy from a pediatric patient with UC alone and a colon biopsy from a pediatric patient without evidence of the disease.
A 14 year-old male presented to the emergency department of our hospital with one-day history of sudden onset of explosive loose stool associated with tenesmus and spotting of fresh red blood and one month history of increasing fatigue. Past medical history was significant for NF type 1 diagnosed in the first year of life based on clinical manifestations and positive family history in maternal grandmother and aunt. The patient also had history of Attention Deficit Hperactivity Disorder (ADHD) pharmacologically treated and resolved three years prior. The patient appeared pale and showed multiple “café au lait” spots on the trunk and extremities. Rectal exam showed erythema without evidence of anal fissures or rectal masses. The initial vital signs were within normal limit (temperature 98.8 °F, blood pressure 124/79, respiratory rate 23, pulse oximetry 99%), except for mild tachycardia (pulse 99). The base line laboratory data confirmed a significant microcytic anemia with hemoglobin 5.1 g/dl, Mean Corpuscolar Volume (MCV) 48 fL, reticulocyte count 2.3%, iron 11 mcg/dl, Total Iron Binding Capacity (TIBC) 399 mcg/dl, and ferritin 1.7 ng/ml. The patient received 1 L normal saline
⁎ Corresponding author. E-mail addresses: [email protected], [email protected] (F. Baratelli).
http://dx.doi.org/10.1016/j.yexmp.2014.02.006 0014-4800/© 2014 Elsevier Inc. All rights reserved.
F. Baratelli et al. / Experimental and Molecular Pathology 96 (2014) 230–234
231
Fig. 1. Sigmoid mucosa, ileocolonoscopy.
and 2 units of packed red blood cells. Following blood transfusion the hemoglobin increased to 7.6 g/dl and the MCV increased to 56.6 fL. Peripheral blood anti-neutrophil cytoplasmic antibodies (ANCA) screen was positive. The atypical perinuclear (P)-ANCA titer was 1:640 units (reference range: b1:20 units). The inflammatory bowel disease panel showed normal levels of myeloperoxidase antibody (b 1.0 unit, (normal range b1.0 unit)), Proteinase-3 antibody (b1.0 unit (normal range b 1.0 unit)), anti-Cerevisiae IgG and anti-Cerevisiae IgA (4.5 units and 5.8 units, respectively, (normal range b20 units)). The patient underwent esophagogastroduodenoscopy and ileocolonoscopy. The mucosa of the stomach and terminal ileum appeared grossly normal. The entire colonic mucosa however showed diffuse edema with a peculiar granular pattern accompanied by focal erythema, shallow ulcers and multiple sessile polyps (Figs. 1A–C). Multiple biopsies were obtained from the gastric mucosa to the rectum. Microscopic examination of tissues from the colonic mucosa revealed a prominent lymphoplasmacytic infiltrate in the lamina propria, associated with goblet cell depletion, cryptitis, crypt abscesses and pseudopolyp formation (Fig. 2A–B). The degree of chronic inflammation ranged from mild (transverse colon and rectum) to moderate (cecum and descending colon), to severe (ascending and sigmoid colon). Pseudovilli formation was also noted in the sigmoid colonic mucosa (Fig. 2B). The microscopic findings along with the clinical manifestations were consistent with the diagnosis of UC. No significant pathologic changes were observed in the gastric and terminal ileal mucosa. Immunohistochemistry stain of the intestinal lesions with c-kit/CD117 revealed a marked increase in mast cells in the lamina propria (Fig. 3B). In addition, Neuron Specific Enolase (NSE) (Fig. 3C) and S100 positive cells (Fig. 3D) highlighted the presence of a Schwann cell component. This pattern of cellularity showing increased number of mast cells and augmented Schwann cell component in the lamina propria was absent in the colonic mucosa of a normal control (Fig. 4A–D) or a patient with UC alone (Fig. 5A–D). In the latter, however, the level of NSE expression by Schwann cells appeared similar to the one observed in our patient (Figs. 3C and 4C).
Following diagnosis, the patient was discharged home in stable condition, on iron fortified diet, oral 5-aminosalicylic acid (5-ASA), Asacol 800 mg (q 8 h), and daily intake of folic acid 1 mg, and ferrous sulfate 325 mg. Materials and methods IHC staining was performed utilizing antibodies purchased from Cellmark AB, Gothenburg, Sweden. The Ventana Benchmark XT and Ventana Benchmark Ultra, Tucson, Arizona, were utilized as automated slide staining system, following the manufacturer’s protocol. Discussion NF type 1 is a common autosomal dominant disease caused by mutation of the tumor suppressor gene NF-1 leading to multiple neuronal, hematopoietic and skeletal pathologies (Jett and Friedman, 2009). Clinical manifestations include “café au lait” spots, neurofibromas, frecklings, Lisch nodules, optic gliomas, and bone deformities. Hallmark of the disease is the development of neurofibromas, composed of Schwann cells, fibroblasts, extracellular matrix and degranulating mast cells (Jett and Friedman, 2009). Mast cells are resident leukocytes known to play a key role in type I hypersensitivity (Walls et al., 2001). Characteristic feature is the presence of cytoplasmic metachromatic granules that occupies approximately 40% of the cell volume. These membrane-enclosed secretory granules originate from the Golgi apparatus. Here, preformed mediators including histamine, proteoglicans, neutral proteinases, cytokines, and newly generated mediators such as eicosanoids and platelet activating factor (PAF) (He, 2004). Mast cell activation is fundamental in mast cell function because only activated mast cells can cause pathophysiologic changes. (He, 2004) Anti-Immunoglobulin (Ig)E, ionophores, stem cell factor (SCF), eosinophil cationic protein and tryptase can activate mast cells (He, 2004; Walls et al., 2001).
Fig. 2. Ulcerative colitis in neurofibromatosis type 1. Figs. 2A–B: Hematoxylin and Eosin stain of sigmoid colon mucosa, 4× (A) and 10× (B).
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F. Baratelli et al. / Experimental and Molecular Pathology 96 (2014) 230–234
A
B
Hematoxylin and eosin, 10x
c-kit, 40x
C
D
S100, 40x
NSE, 40x
Fig. 3. Ulcerative colitis in neurofibromatosis type 1.
Studies have demonstrated the role of mast cells in neurofibroma formation through the release of their degranulation products and secretion of cytokines such as TGF-β, histamine and heparin and metalloproteinases (Staser et al., 2010, 2013; Trucker et al., 2011; Yoshida
A
et al., 2010). In particular hyperactivation of c-kit pathway in a NF1 haploinsufficient microenvironment is required for neurofibroma formation and progression highlighting the interaction between Schwann cells and mast cells (Chen et al., 2010). Chen S et al. (Chen et al., 2010),
B
Hematoxylin and eosin, 10x
C
c-kit, 40x
D
NSE, 40x
S100, 40x Fig. 4. Negative control.
F. Baratelli et al. / Experimental and Molecular Pathology 96 (2014) 230–234
A
233
B
Hematoxylin and eosin, 10x
c-kit, 40x
C
D
S100, 40x
NSE, 40x
Fig. 5. Ulcerative colitis alone.
demonstrated the role of Schwann cells at inducing mast cell degranulation via secretion of Stem Cell Factor (SCF), a c-kit ligand, in vitro. In addition studies have shown that tissue histamine level is higher in neurofibroma compared to normal skin, and 20% of patients with NF1 develop pruritus (Khosrotehrani et al., 2005). A large number of degranulated mast cells has been detected in neurofibroma; this finding has been correlated with increased level of nerve growth factor (NGF), which triggers mast cell degranulation and release of inflammatory mediators (Staser et al., 2010, 2013; Trucker et al., 2011; Yoshida et al., 2010). A pathogenetic role of mast cells has also been postulated in inflammatory bowel disease, including UC where they may play a role in regulating inflammation in concert with neuronal structures (He, 2004; Stoyanova and Gulubova, 2002). Mast cells are numerous in the gastrointestinal tract. Multiple studies have shown increased number of mast cells in UC and evidence of degranulation by transmission electron microscopy technique (Balazas et al., 1989; Dvorak et al., 1992; He, 2004). Similarly, evidence of mast cell degranulation has been demonstrated with immunohistochemistry techniques using antibodies to human tryptase or chymase, exclusive antigens of human mast cells (Crivellato et al., 2003). Studies have also shown that the number of mast cells in UC is significantly greater in active disease versus remission phase (Kashiwase et al., 2008; Stasikowska-Kanicka et al., 2012). King T et al. (King et al., 1992) observed a clear demarcation between mast cell-enriched, inflamed intestinal lamina propria and normal tissue suggesting that mast cells may act either by further damaging or limiting the expansion of cell injury. Interaction of mast cells with neurons appears to induce progression and maintenance of IBD (He, 2004; Tavakkoli et al., 2009). Patients with IBD tend to overreact to multiple stressors with mucosal mast cell degranulation and epithelial damage (Farhadi, 2007). Substance P in particular seems to play a role because it is released in the nerve ending throughout the gastrointestinal tract and co-localizes with mast cells (Stoyanova and Gulubova, 2002; Tavakkoli et al., 2009). Stoyonova II et al.(Stoyanova and Gulubova, 2002) reported an increased number of nerve fibers staining
for substance P and serotonin in all layers of the intestinal wall of UC patients (Stoyanova and Gulubova, 2002). The authors also reported increase number of mast cells positive for tryptase, serotonin and substance P in the basal lamina of intestinal glands. Substance P has been shown to preferentially enhance mucosal mast cell mediators' secretion in active IBD (Raithel, 1999) suggesting that interaction between neuronal fibers and mast cells may lead to amplification and perpetuation of inflammatory damage in IBD. Conclusion Analysis of the literature has shown only one report of concurrent association of NF type I and UC (Bretagne et al., 1980; Tavakkoli et al., 2009). Here we document a pediatric case of newly diagnosed UC in history of NF type 1. Microscopic examination and immunohistochemistry staining of the colonic mucosa showed significant increase of mast cells associated with augmented Schwann cell component in the lamina propria. Our observation is in line with recent findings suggesting a possible pathogenetic role of mast cells and Schwann cells in UC and NF type 1. The clinical significance of these findings is still unknown. Further investigation is warranted to investigate the correlation between these two pathologies and whether NF-type 1 may promote development of UC and/or UC may trigger progression of neurofibromatosis lesions. Elucidation of these issues may impact therapeutic approaches of UC and NF type 1. Conflict of interest The authors declare that there are no conflicts of interest. Acknowledgments We thank the Histology laboratory at Harbor-UCLA , Torrance, California, for performing the IHC staining of the tissue biopsies.
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F. Baratelli et al. / Experimental and Molecular Pathology 96 (2014) 230–234
References Balazas, M., Illyes, G., Vadasz, G., 1989. Mast cells in ulcerative colitis. Quantitative and ultrastructural studies. Virchows Arch. B Cell. Pathol. Incl. Mol. Pathol. 57, 353–360. Bretagne, J.F., et al., 1980. Ulcerative hemorrhagic colitis, hyperparathyroidism and Recklinghausen's disease. Gastroenterol. Clin. Biol. 4, 497–498. Chen, S., et al., 2010. Nf1−/− Schwann cell-conditioned medium modulates mast cell degranulation by c-kit-mediated hyperactivation of phosphatidylinositol 3-kinase. Am. J. Pathol. 177, 3125–3132. Crivellato, E., et al., 2003. Low mast cell density in the human duodenal mucosa from chronic inflammatory duodenal bowel disorders is associated with defective villous architecture. Eur. J. Clin. Invest. 33, 601–610. Dvorak, A.M., et al., 1992. Ultrastructural evidence for piecemeal and anaphylactic degranulation of human gut mucosal mast cells in vivo. Int. Arch. Allergy Immunol. 99, 74–83. Farhadi, A., 2007. Mucosal mast cells are pivotal elements in inflammatory bowel disease that connect the dots: stress, intestinal hypermeability and inflammation. World J. Gastroenterol. 13, 3027–3030. He, S.-H., 2004. Key role of mast cells and their major secretory products in inflammatory bowel disease. World J. Gastroenterol. 10, 209–318. Jett, K., Friedman, J.M., 2009. Clinical and genetic aspects of neurofibromatosis 1. Genet. Med. 12, 1–11. Kashiwase, Y., et al., 2008. Quantitative analysis of mast cells in benign and malignant colonic lesions: immunohistochemical study on formalin-fixed, paraffin-embedded tissues. Allergol. Immunopathol. 36, 271–276.
Khosrotehrani, K., et al., 2005. Subcutaneous neurofibromas are associated with mortality in neurofibromatosis 1: a cohort study of 703 patients. Am. J. Med. Genet. 132A, 49–53. King, T., et al., 1992. Colonic mucosal mast cell distribution at line of demarcation of active ulcerative colitis. Dig. Dis. Sci. 37, 490-45. Raithel, M., 1999. Effect of substance P on histamine secretion from gut mucosa in inflammatory bowel disease. Scand. J. Gastroenterol. 34, 496–503. Staser, k, Yang, F.-C., Clapp, D.W., 2010. Plexiform neurofibroma genesis: question of NF1gene dose and hyperactive mast cells. Curr. Opin. Hematol. 17, 287–293. Staser, k, Yang, F.-C., Clapp, D.W., 2013. Mast cells and the neurofibroma microenvironment. Blood 116, 157–164. Stasikowska-Kanicka, O., et al., 2012. Mast cells and eosinophils are involved in activation of ulcerative colitis. Adv. Med. Sci. 11, 1–7. Stoyanova, I.I., Gulubova, M.V., 2002. Mast cells and inflammatory mediators in chronic ulcerative colitis. Acta Histochem. 104, 185–192. Tavakkoli, H., et al., 2009. Ulcerative colitis and neurofibromatosis type 1 with bilateral psoas muscle: a case report. J. Res. Med. Sci. 14, 261–265. Trucker, T., et al., 2011. Different patterns of mast cells distinguish diffuse from encapsulated neurofibromas in patients with neurofibromatosis type 1. J. Histochem. Cytochem. 59, 584–590. Walls, A.F., et al., 2001. Roles of mast cell and basophil in asthma. Clin. Exp. Allergy Rev. 1, 68–72. Yoshida, Y., Adachi, K., Yamamoto, O., 2010. Local mast cell histamine levels in neurofibromatosis type 1. Acta Derm. Venereol. 90, 1–3.
Contents lists available at ScienceDirect
Experimental and Molecular Pathology journal homepage: www.elsevier.com/locate/yexmp
Do mast cells play a pathogenetic role in neurofibromatosis type 1 and ulcerative colitis? Felicita Baratelli a,⁎, Mary Le a, George B. Gershman b, Samuel W. French a a b
Harbor–UCLA Medical Center, Department of Pathology, 1000 West Carson, Torrance, 90502 CA, United States Division of Gastroenterology, 1000 West Carson, Torrance 90502, CA, United States
a r t i c l e
i n f o
Article history: Received 11 February 2014 Available online 26 February 2014 Keywords: Mast cell Neurofibromatosis type 1 Ulcerative colitis Inflammatory bowel disease
a b s t r a c t Concurrent association of neurofibromatosis type I and ulcerative colitis has been reported in one clinical case (Tavakkoli et al., 2009). Although this association may represent a casual finding, a common pathophysiology is postulated. Mast cells have been implicated in the pathogenesis of both neurofibromatosis type 1 and ulcerative colitis (He, 2004; Yoshida et al., 2010). Mast cells are typically present in neurofibromas microenvironment where they appear to contribute to tumor initiation, progression and angiogenesis (Staser et al., 2010, 2013). Moreover, interaction of mast cells with nerves throughout the gastrointestinal tract has been correlated with progression and maintenance of ulcerative colitis (Stoyanova and Gulubova, 2002). We describe a 14 year-old male with history of neurofibromatosis type 1 and new onset of ulcerative colitis diagnosed on clinical and histological findings. On gross examination the entire colonic mucosa appeared edematous showing a peculiar granular pattern, with focal erythema, shallow ulcers and multiple sessile polyps. Hematoxylin and eosin stained tissue biopsies from the colonic mucosa showed chronic inflammatory bowel disease, severe activity, consistent with chronic ulcerative colitis. Immunohistochemistry stain of the intestinal lesions revealed high expression of Neuron Specific Enolase (NSE) and S100 highlighting the presence of a Schwann cell component. In addition, c-kit/CD117 positive stain indicated a marked increase of mast cells in the lamina propria. This pattern of cellularity in the lamina propria showing increased mast cells and augmented Schwann cell component was absent in the colonic mucosa of a normal control or a patient with ulcerative colitis alone. Our observation supports the evidence of a pathogenetic role of the mast cell in ulcerative colitis associated with neurofibromatosis type 1. Further investigations are warranted to confirm the significance of this correlation as it may impact therapeutic approaches of these pathologies. © 2014 Elsevier Inc. All rights reserved.
Introduction
Case report
Concomitant association of histologically proven ulcerative colitis (UC) and neurofibromatosis (NF) type 1 is a rare finding documented in one adult clinical case by Tavakkoli et al. (1) Previous literature identified mast cells as important elements involved in both pathogenesis of inflammatory bowel disease and development of neurofibromas (2, 3). Here we report a pediatric case of newly diagnosed UC in NF type 1. We evaluated the presence of mast cells and Schwann cells in the colon tissue biopsy diagnosed with UC by immunohistochemistry (IHC). Mast cells were identified by expression of CD117/c-kit, and Schwann cells by expression of Neuron Specific Enolase (NSE) and S100. As control tissue, we utilized a colon biopsy from a pediatric patient with UC alone and a colon biopsy from a pediatric patient without evidence of the disease.
A 14 year-old male presented to the emergency department of our hospital with one-day history of sudden onset of explosive loose stool associated with tenesmus and spotting of fresh red blood and one month history of increasing fatigue. Past medical history was significant for NF type 1 diagnosed in the first year of life based on clinical manifestations and positive family history in maternal grandmother and aunt. The patient also had history of Attention Deficit Hperactivity Disorder (ADHD) pharmacologically treated and resolved three years prior. The patient appeared pale and showed multiple “café au lait” spots on the trunk and extremities. Rectal exam showed erythema without evidence of anal fissures or rectal masses. The initial vital signs were within normal limit (temperature 98.8 °F, blood pressure 124/79, respiratory rate 23, pulse oximetry 99%), except for mild tachycardia (pulse 99). The base line laboratory data confirmed a significant microcytic anemia with hemoglobin 5.1 g/dl, Mean Corpuscolar Volume (MCV) 48 fL, reticulocyte count 2.3%, iron 11 mcg/dl, Total Iron Binding Capacity (TIBC) 399 mcg/dl, and ferritin 1.7 ng/ml. The patient received 1 L normal saline
⁎ Corresponding author. E-mail addresses: [email protected], [email protected] (F. Baratelli).
http://dx.doi.org/10.1016/j.yexmp.2014.02.006 0014-4800/© 2014 Elsevier Inc. All rights reserved.
F. Baratelli et al. / Experimental and Molecular Pathology 96 (2014) 230–234
231
Fig. 1. Sigmoid mucosa, ileocolonoscopy.
and 2 units of packed red blood cells. Following blood transfusion the hemoglobin increased to 7.6 g/dl and the MCV increased to 56.6 fL. Peripheral blood anti-neutrophil cytoplasmic antibodies (ANCA) screen was positive. The atypical perinuclear (P)-ANCA titer was 1:640 units (reference range: b1:20 units). The inflammatory bowel disease panel showed normal levels of myeloperoxidase antibody (b 1.0 unit, (normal range b1.0 unit)), Proteinase-3 antibody (b1.0 unit (normal range b 1.0 unit)), anti-Cerevisiae IgG and anti-Cerevisiae IgA (4.5 units and 5.8 units, respectively, (normal range b20 units)). The patient underwent esophagogastroduodenoscopy and ileocolonoscopy. The mucosa of the stomach and terminal ileum appeared grossly normal. The entire colonic mucosa however showed diffuse edema with a peculiar granular pattern accompanied by focal erythema, shallow ulcers and multiple sessile polyps (Figs. 1A–C). Multiple biopsies were obtained from the gastric mucosa to the rectum. Microscopic examination of tissues from the colonic mucosa revealed a prominent lymphoplasmacytic infiltrate in the lamina propria, associated with goblet cell depletion, cryptitis, crypt abscesses and pseudopolyp formation (Fig. 2A–B). The degree of chronic inflammation ranged from mild (transverse colon and rectum) to moderate (cecum and descending colon), to severe (ascending and sigmoid colon). Pseudovilli formation was also noted in the sigmoid colonic mucosa (Fig. 2B). The microscopic findings along with the clinical manifestations were consistent with the diagnosis of UC. No significant pathologic changes were observed in the gastric and terminal ileal mucosa. Immunohistochemistry stain of the intestinal lesions with c-kit/CD117 revealed a marked increase in mast cells in the lamina propria (Fig. 3B). In addition, Neuron Specific Enolase (NSE) (Fig. 3C) and S100 positive cells (Fig. 3D) highlighted the presence of a Schwann cell component. This pattern of cellularity showing increased number of mast cells and augmented Schwann cell component in the lamina propria was absent in the colonic mucosa of a normal control (Fig. 4A–D) or a patient with UC alone (Fig. 5A–D). In the latter, however, the level of NSE expression by Schwann cells appeared similar to the one observed in our patient (Figs. 3C and 4C).
Following diagnosis, the patient was discharged home in stable condition, on iron fortified diet, oral 5-aminosalicylic acid (5-ASA), Asacol 800 mg (q 8 h), and daily intake of folic acid 1 mg, and ferrous sulfate 325 mg. Materials and methods IHC staining was performed utilizing antibodies purchased from Cellmark AB, Gothenburg, Sweden. The Ventana Benchmark XT and Ventana Benchmark Ultra, Tucson, Arizona, were utilized as automated slide staining system, following the manufacturer’s protocol. Discussion NF type 1 is a common autosomal dominant disease caused by mutation of the tumor suppressor gene NF-1 leading to multiple neuronal, hematopoietic and skeletal pathologies (Jett and Friedman, 2009). Clinical manifestations include “café au lait” spots, neurofibromas, frecklings, Lisch nodules, optic gliomas, and bone deformities. Hallmark of the disease is the development of neurofibromas, composed of Schwann cells, fibroblasts, extracellular matrix and degranulating mast cells (Jett and Friedman, 2009). Mast cells are resident leukocytes known to play a key role in type I hypersensitivity (Walls et al., 2001). Characteristic feature is the presence of cytoplasmic metachromatic granules that occupies approximately 40% of the cell volume. These membrane-enclosed secretory granules originate from the Golgi apparatus. Here, preformed mediators including histamine, proteoglicans, neutral proteinases, cytokines, and newly generated mediators such as eicosanoids and platelet activating factor (PAF) (He, 2004). Mast cell activation is fundamental in mast cell function because only activated mast cells can cause pathophysiologic changes. (He, 2004) Anti-Immunoglobulin (Ig)E, ionophores, stem cell factor (SCF), eosinophil cationic protein and tryptase can activate mast cells (He, 2004; Walls et al., 2001).
Fig. 2. Ulcerative colitis in neurofibromatosis type 1. Figs. 2A–B: Hematoxylin and Eosin stain of sigmoid colon mucosa, 4× (A) and 10× (B).
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F. Baratelli et al. / Experimental and Molecular Pathology 96 (2014) 230–234
A
B
Hematoxylin and eosin, 10x
c-kit, 40x
C
D
S100, 40x
NSE, 40x
Fig. 3. Ulcerative colitis in neurofibromatosis type 1.
Studies have demonstrated the role of mast cells in neurofibroma formation through the release of their degranulation products and secretion of cytokines such as TGF-β, histamine and heparin and metalloproteinases (Staser et al., 2010, 2013; Trucker et al., 2011; Yoshida
A
et al., 2010). In particular hyperactivation of c-kit pathway in a NF1 haploinsufficient microenvironment is required for neurofibroma formation and progression highlighting the interaction between Schwann cells and mast cells (Chen et al., 2010). Chen S et al. (Chen et al., 2010),
B
Hematoxylin and eosin, 10x
C
c-kit, 40x
D
NSE, 40x
S100, 40x Fig. 4. Negative control.
F. Baratelli et al. / Experimental and Molecular Pathology 96 (2014) 230–234
A
233
B
Hematoxylin and eosin, 10x
c-kit, 40x
C
D
S100, 40x
NSE, 40x
Fig. 5. Ulcerative colitis alone.
demonstrated the role of Schwann cells at inducing mast cell degranulation via secretion of Stem Cell Factor (SCF), a c-kit ligand, in vitro. In addition studies have shown that tissue histamine level is higher in neurofibroma compared to normal skin, and 20% of patients with NF1 develop pruritus (Khosrotehrani et al., 2005). A large number of degranulated mast cells has been detected in neurofibroma; this finding has been correlated with increased level of nerve growth factor (NGF), which triggers mast cell degranulation and release of inflammatory mediators (Staser et al., 2010, 2013; Trucker et al., 2011; Yoshida et al., 2010). A pathogenetic role of mast cells has also been postulated in inflammatory bowel disease, including UC where they may play a role in regulating inflammation in concert with neuronal structures (He, 2004; Stoyanova and Gulubova, 2002). Mast cells are numerous in the gastrointestinal tract. Multiple studies have shown increased number of mast cells in UC and evidence of degranulation by transmission electron microscopy technique (Balazas et al., 1989; Dvorak et al., 1992; He, 2004). Similarly, evidence of mast cell degranulation has been demonstrated with immunohistochemistry techniques using antibodies to human tryptase or chymase, exclusive antigens of human mast cells (Crivellato et al., 2003). Studies have also shown that the number of mast cells in UC is significantly greater in active disease versus remission phase (Kashiwase et al., 2008; Stasikowska-Kanicka et al., 2012). King T et al. (King et al., 1992) observed a clear demarcation between mast cell-enriched, inflamed intestinal lamina propria and normal tissue suggesting that mast cells may act either by further damaging or limiting the expansion of cell injury. Interaction of mast cells with neurons appears to induce progression and maintenance of IBD (He, 2004; Tavakkoli et al., 2009). Patients with IBD tend to overreact to multiple stressors with mucosal mast cell degranulation and epithelial damage (Farhadi, 2007). Substance P in particular seems to play a role because it is released in the nerve ending throughout the gastrointestinal tract and co-localizes with mast cells (Stoyanova and Gulubova, 2002; Tavakkoli et al., 2009). Stoyonova II et al.(Stoyanova and Gulubova, 2002) reported an increased number of nerve fibers staining
for substance P and serotonin in all layers of the intestinal wall of UC patients (Stoyanova and Gulubova, 2002). The authors also reported increase number of mast cells positive for tryptase, serotonin and substance P in the basal lamina of intestinal glands. Substance P has been shown to preferentially enhance mucosal mast cell mediators' secretion in active IBD (Raithel, 1999) suggesting that interaction between neuronal fibers and mast cells may lead to amplification and perpetuation of inflammatory damage in IBD. Conclusion Analysis of the literature has shown only one report of concurrent association of NF type I and UC (Bretagne et al., 1980; Tavakkoli et al., 2009). Here we document a pediatric case of newly diagnosed UC in history of NF type 1. Microscopic examination and immunohistochemistry staining of the colonic mucosa showed significant increase of mast cells associated with augmented Schwann cell component in the lamina propria. Our observation is in line with recent findings suggesting a possible pathogenetic role of mast cells and Schwann cells in UC and NF type 1. The clinical significance of these findings is still unknown. Further investigation is warranted to investigate the correlation between these two pathologies and whether NF-type 1 may promote development of UC and/or UC may trigger progression of neurofibromatosis lesions. Elucidation of these issues may impact therapeutic approaches of UC and NF type 1. Conflict of interest The authors declare that there are no conflicts of interest. Acknowledgments We thank the Histology laboratory at Harbor-UCLA , Torrance, California, for performing the IHC staining of the tissue biopsies.
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References Balazas, M., Illyes, G., Vadasz, G., 1989. Mast cells in ulcerative colitis. Quantitative and ultrastructural studies. Virchows Arch. B Cell. Pathol. Incl. Mol. Pathol. 57, 353–360. Bretagne, J.F., et al., 1980. Ulcerative hemorrhagic colitis, hyperparathyroidism and Recklinghausen's disease. Gastroenterol. Clin. Biol. 4, 497–498. Chen, S., et al., 2010. Nf1−/− Schwann cell-conditioned medium modulates mast cell degranulation by c-kit-mediated hyperactivation of phosphatidylinositol 3-kinase. Am. J. Pathol. 177, 3125–3132. Crivellato, E., et al., 2003. Low mast cell density in the human duodenal mucosa from chronic inflammatory duodenal bowel disorders is associated with defective villous architecture. Eur. J. Clin. Invest. 33, 601–610. Dvorak, A.M., et al., 1992. Ultrastructural evidence for piecemeal and anaphylactic degranulation of human gut mucosal mast cells in vivo. Int. Arch. Allergy Immunol. 99, 74–83. Farhadi, A., 2007. Mucosal mast cells are pivotal elements in inflammatory bowel disease that connect the dots: stress, intestinal hypermeability and inflammation. World J. Gastroenterol. 13, 3027–3030. He, S.-H., 2004. Key role of mast cells and their major secretory products in inflammatory bowel disease. World J. Gastroenterol. 10, 209–318. Jett, K., Friedman, J.M., 2009. Clinical and genetic aspects of neurofibromatosis 1. Genet. Med. 12, 1–11. Kashiwase, Y., et al., 2008. Quantitative analysis of mast cells in benign and malignant colonic lesions: immunohistochemical study on formalin-fixed, paraffin-embedded tissues. Allergol. Immunopathol. 36, 271–276.
Khosrotehrani, K., et al., 2005. Subcutaneous neurofibromas are associated with mortality in neurofibromatosis 1: a cohort study of 703 patients. Am. J. Med. Genet. 132A, 49–53. King, T., et al., 1992. Colonic mucosal mast cell distribution at line of demarcation of active ulcerative colitis. Dig. Dis. Sci. 37, 490-45. Raithel, M., 1999. Effect of substance P on histamine secretion from gut mucosa in inflammatory bowel disease. Scand. J. Gastroenterol. 34, 496–503. Staser, k, Yang, F.-C., Clapp, D.W., 2010. Plexiform neurofibroma genesis: question of NF1gene dose and hyperactive mast cells. Curr. Opin. Hematol. 17, 287–293. Staser, k, Yang, F.-C., Clapp, D.W., 2013. Mast cells and the neurofibroma microenvironment. Blood 116, 157–164. Stasikowska-Kanicka, O., et al., 2012. Mast cells and eosinophils are involved in activation of ulcerative colitis. Adv. Med. Sci. 11, 1–7. Stoyanova, I.I., Gulubova, M.V., 2002. Mast cells and inflammatory mediators in chronic ulcerative colitis. Acta Histochem. 104, 185–192. Tavakkoli, H., et al., 2009. Ulcerative colitis and neurofibromatosis type 1 with bilateral psoas muscle: a case report. J. Res. Med. Sci. 14, 261–265. Trucker, T., et al., 2011. Different patterns of mast cells distinguish diffuse from encapsulated neurofibromas in patients with neurofibromatosis type 1. J. Histochem. Cytochem. 59, 584–590. Walls, A.F., et al., 2001. Roles of mast cell and basophil in asthma. Clin. Exp. Allergy Rev. 1, 68–72. Yoshida, Y., Adachi, K., Yamamoto, O., 2010. Local mast cell histamine levels in neurofibromatosis type 1. Acta Derm. Venereol. 90, 1–3.
