Mast Cell Mediators Research Articles

Clinical challenge for gastroenterologists-Gastrointestinal manifestations of systemic mastocytosis: A comprehensive review.

Mastocytosis is a rare and heterogeneous disease characterized by various clinical and biological features that affect different prognoses and treatments. The disease is usually divided into 2 principal categories: cutaneous and systemic disease (SM). Clinical features can be related to mast cell (MC) mediator release or pathological MC infiltration. SM is a disease often hard to identify, and the diagnosis is based on clinical, biological, histological, and molecular criteria with different specialists involved in the patient’s clinical work-up. Among all manifestations of the disease, gastrointestinal (GI) symptoms are common, being present in 14%-85% of patients, and can significantly impair the quality of life. Here we review the data regarding GI involvement in SM, in terms of clinical presentations, histological and endoscopic features, the pathogenesis of GI symptoms, and their treatment.

Front Cover: Resveratrol Attenuates Mast Cell Mediated Allergic Reactions: Potential for Use as a Nutraceutical in Allergic Diseases?

Mol. Nutr. Food Res. 2022, 66, 202200170 DOI: 10.1002/mnfr.202200170 Resveratrol, a polyphenol found in red grapes, inhibits release of pre-stored and newly synthesized pro-inflammatory mediators in mast cells activated by various stimuli. Signaling pathways inhibited by resveratrol include among others MAP kinases ERK and p38 as well as transcription factors STAT3 and NF-κB. This is reported by Axel Lorentz and co-workers in article number 2200170.

Temporal variation of tryptase and interlaboratory variability

The diagnosis of anaphylaxis and mast cell activation syndrome (MCAS) relies largely on history with laboratories assisting in diagnosis as an objective demonstration of mast cell activation.1-3 Serum tryptase is the most readily available and typically used marker in this regard.4 Consensus expert opinion recommends using an objective rise in mast cell mediators as a requirement for the diagnosis of MCAS, and 1 equation that is typically used is an increase in serum tryptase level above the individual's baseline of 20% plus 2 ng/mL.

Neuropathic pain and itch: mechanisms in allergic conjunctivitis.

Allergic conjunctivitis is highly prevalent and affects up to one third of the general population. The current understanding of the pathophysiology and therapeutic strategies center around the type 2 inflammatory pathway. However, there is an increasing body of evidence that suggests neurogenic mechanisms also play a role in allergic inflammation, with a substantial proportion of allergic conjunctivitis patients experiencing both ocular itch and pain. Unmyelinated C fibres on the ocular surface transmit histaminergic itch and can be directly activated by mast cell mediators. The conjunctival mucosa also contains TRPV1+ (histamine-dependent) and TRPA1+ (histamine-independent) neurons that enhance ocular pain and itch in allergic conjunctivitis. Allergen-complexed IgE also binds directly to FcεRI expressed on peripheral neurons. Environmental aeroallergens can also directly stimulate neuronal nociceptors to release inflammatory substances. Allergic inflammation thus stimulates nerve terminals to release vasoactive and inflammatory neuropeptides, leading to a cyclical neuronal dysregulation that augments mast cell activity. These repetitive cycles lead to both peripheral and central sensitization and neuronal plasticity, resulting in decreased itch/pain thresholds and a heightened itch/pain response. Neurogenic mechanisms including peripheral and central sensitization may drive chronic ocular itch and pain secondary to allergic inflammation. Research into these pathways may help to identify therapeutic targets in allergic conjunctivitis patients with refractory symptoms.

Presence of neoplastic mast cells in ascites in advanced systemic mastocytosis

Systemic mastocytosis (SM) is characterized by clonal expansion of mast cells (MCs) in different organs, usually in bone marrow (BM) and variably also in other tissues like skin and gastrointestinal tract.1-3 Clinical manifestations are heterogeneous and can include MC mediator symptoms and a dysfunction of various organ systems, such as cytopenia, hepatosplenomegaly, ascites, and weight loss. Most patients with SM carry the activating mutation KIT D816V. Typically, patients with SM are also characterized by elevated serum levels of tryptase, an enzyme produced by MCs, and aberrant expression of CD25 and/or CD2 on MCs in BM and possibly other tissues.

Anti-neoplastic action of Cimetidine/Vitamin C on histamine and the PI3K/AKT/mTOR pathway in Ehrlich breast cancer

The main focus of our study is to assess the anti-cancer activity of cimetidine and vitamin C via combating the tumor supportive role of mast cell mediators (histamine, VEGF, and TNF-α) within the tumor microenvironment and their effect on the protein kinase A(PKA)/insulin receptor substrate-1(IRS-1)/phosphatidylinositol-3-kinase (PI3K)/serine/threonine kinase-1 (AKT)/mammalian target of rapamycin (mTOR) cue in Ehrlich induced breast cancer in mice. In vitro study was carried out to evaluate the anti-proliferative activity and combination index (CI) of the combined drugs. Moreover, the Ehrlich model was induced in mice via subcutaneous injection of Ehrlich ascites carcinoma cells (EAC) in the mammary fat pad, and then they were left for 9 days to develop obvious solid breast tumor. The combination therapy possessed the best anti-proliferative effect, and a CI < 1 in the MCF7 cell line indicates a synergistic type of drug interaction. Regarding the in vivo study, the combination abated the elevation in the tumor volume, and serum tumor marker carcinoembryonic antigen (CEA) level. The serum vascular endothelial growth factor (VEGF) level and immunohistochemical staining for CD34 as markers of angiogenesis were mitigated. Additionally, it reverted the state of oxidative stress and inflammation. Meanwhile, it caused an increment in apoptosis, which prevents tumor survival. Furthermore, it tackled the elevated histamine and cyclic adenosine monophosphate (cAMP) levels, preventing the activation of the (PKA/IRS-1/PI3K/AKT/mTOR) cue. Finally, we concluded that the synergistic combination provided a promising anti-neoplastic effect via reducing the angiogenesis, oxidative stress, increasing apoptosis,as well as inhibiting the activation of PI3K/AKT/mTOR cue, and suggesting its use as a treatment option for breast cancer.

Mast cell activation syndrome and the link with long COVID

Mast cells are innate immune cells found in connective tissues throughout the body, most prevalent at tissue-environment interfaces. They possess multiple cell-surface receptors which react to various stimuli and, after activation, release many mediators including histamine, heparin, cytokines, prostaglandins, leukotrienes and proteases. In mast cell activation syndrome, excessive amounts of inflammatory mediators are released in response to triggers such as foods, fragrances, stress, exercise, medications or temperature changes. Diagnostic markers may be difficult to assess because of their rapid degradation; these include urinary N-methyl histamine, urinary prostaglandins D2, DM and F2α and serum tryptase (which is stable) in the UK. Self-management techniques, medications and avoiding triggers may improve quality of life. Treatments include mast cell mediator blockers, mast cell stabilisers and anti-inflammatory agents. ‘Long COVID’ describes post-COVID-19 syndrome when symptoms persist for more than 12 weeks after initial infection with no alternative diagnosis. Both mast cell activation syndrome and long COVID cause multiple symptoms. It is theorised that COVID-19 infection could lead to exaggeration of existing undiagnosed mast cell activation syndrome, or could activate normal mast cells owing to the persistence of viral particles. Other similarities include the relapse-remission cycle and improvements with similar treatments. Importantly, however, aside from mast cell disorders, long COVID could potentially be attributed to several other conditions.

Mastocytosis. General concepts, view on patient management, examples of clinical course of the disease

Background. Mastocytosis is a disease characterized by the presence of mast cells in various organs. The skin is affected most often. Almost every patient diagnosed with mastocytosis has skin lesions. This disease is characterized by redness, itching, abdominal pain, diarrhea, musculoskeletal pain, hypotension. These features result from the release of the mast cell mediator and its infiltration into the target organs. Materials and methods. This article describes the symptoms and signs of each and systemic mastocytosis, the principles of their diagnosis, based on recently published іnternational recommendations. Results. According to the 2016 World Health Organization classification, mastocytosis can be divided into cutaneous mastocytosis, systemic mastocytosis and mast cell sarcoma. Cutaneous mastocytosis is divided into three subtypes: maculopapular cutaneous mastocytosis, diffuse cutaneous mastocytosis and cutaneous mastocytoma. Permanent telangiectasia of the macular eruptive form is no longer considered a separate unit. Systemic mastocytosis, in turn, is also divided into indolent, smoldering, aggressive and associated with hematological tumors. Conclusions. Cutaneous manifestations of mastocytosis may vary with age. The classification of cutaneous mastocytosis has recently been updated. As a rule, in patients with mastocytosis in childhood the disease occurs as cutaneous mastocytosis and spontaneously regresses during puberty. On the contrary, in adult patients, despite skin lesions, systemic lesions are often observed, and the course of the disease is usually chronic. That is, patients of any age can be affected. The article describes the causes and pathogenesis of mastocytosis with an overview of clinical features, approach to diagnosis and therapy depending on age and severity of the disease. Clinical cases for visual acquaintance with a clinical picture of various forms of mastocytosis are resulted.

Target Therapies for Systemic Mastocytosis: An Update.

Systemic mastocytosis (SM) results from a clonal proliferation of abnormal mast cells (MCs) in extra-cutaneous organs. It could be divided into indolent SM, smoldering SM, SM with an associated hematologic (non-MC lineage) neoplasm, aggressive SM, and mast cell leukemia. SM is generally associated with the presence of a gain-of-function somatic mutation in KIT at codon 816. Clinical features could be related to MC mediator release or to uncontrolled infiltration of MCs in different organs. Whereas indolent forms have a near-normal life expectancy, advanced diseases have a poor prognosis with short survival times. Indolent forms should be considered for symptom-directed therapy, while cytoreductive therapy represents the first-line treatment for advanced diseases. Since the emergence of tyrosine kinase inhibitors (TKIs), KIT inhibition has been an attractive approach. Initial reports showed that only the rare KITD816V negative cases were responsive to first-line TKI imatinib. The development of new TKIs with activity against the KITD816V mutation, such as midostaurin or avapritinib, has changed the management of this disease. This review aims to focus on the available clinical data of therapies for SM and provide insights into possible future therapeutic targets.

Drugs and Vaccines Hypersensitivity in Children with Mastocytosis.

Mastocytosis, a heterogeneous mastcell disease, include three different entities: cutaneous mastocytosis, systemic mastocytosis (SM) and mast-cell sarcoma. Tryptase levels can differentiate cutaneous mastocytosis from SM. In mastocytosis, quick onset drug hypersensitivity reactions (DHRs) that are facilitated by mastcell mediators, are investigated in adults. Due to the limited number of children with mastcell disease and increased serum tryptase levels, the role of drugs in this age group is less studied. In this review, we critically assessed relevant papers related with immediate DHRs in children with mastocytosis and discuss practical issues of the management. In childhood mastocytosis, anaphylaxis is frequently idiopathic, and elevated level of basal tryptase, and high burden of disease may increase the risk. Among drugs, antibiotics, NSAIDs and opioids can potentially induce anaphylaxis, anyway avoidance should be recommended only in case of previous reactions. Moreover, vaccinations are not contraindicated in patients with mastocytosis. The risk of severe systemic reactions after drugs intake seems to be extremely low and in general lower in children than in adults. Anyway, studies on this topic especially focusing on children, are missing to state final recommendations.

Altered innate immune profile in blood of systemic mastocytosis patients.

BackgroundMast cells (MC) from systemic mastocytosis (SM) patients release MC mediators that lead to an altered microenvironment with potential consequences on innate immune cells, such as monocytes and dendritic cells (DC). Here we investigated the distribution and functional behaviour of different populations of blood monocytes and DC among distinct diagnostic subtypes of SM.MethodsOverall, we studied 115 SM patients ‐ 45 bone marrow mastocytosis (BMM), 61 indolent SM (ISM), 9 aggressive SM (ASM)‐ and 32 healthy donors (HD). Spontaneous and in vitro‐stimulated cytokine production by blood monocytes, and their plasma levels, together with the distribution of different subsets of blood monocytes and DCs, were investigated.ResultsSM patients showed increased plasma levels and spontaneous production by blood monocytes of IL1β, IL6, IL8, TNFα and IL10, associated with an exhausted ability of LPS + IFNγ‐stimulated blood monocytes to produce IL1β and TGFβ. SM (particularly ISM) patients also showed decreased counts of total monocytes, at the expense of intermediate monocytes and non‐classical monocytes. Interestingly, while ISM and ASM patients had decreased numbers of plasmacytoid DC and myeloid DC (and their major subsets) in blood, an expansion of AXL+ DC was specifically encountered in BMM cases.ConclusionThese results demonstrate an altered distribution of blood monocytes and DC subsets in SM associated with constitutive activation of functionally impaired blood monocytes and increased plasma levels of a wide variety of inflammatory cytokines, reflecting broad activation of the innate immune response in mastocytosis.

The Role of Crosstalk of Immune Cells in Pathogenesis of Chronic Spontaneous Urticaria.

Chronic spontaneous urticaria (CSU) is defined as recurrent episodes of spontaneous wheal development and/or angioedema for more than six weeks and at least twice a week. The core link in the pathogenesis of CSU is the activation of mast cells, T cells, eosinophils, and other immune cells infiltrating around the small venules of the lesion. Increased vascular permeability, vasodilatation, and recruitment of inflammatory cells directly depend on mast cell mediators’ release. Complex regulatory systems tightly influence the critical roles of mast cells in the local microenvironment. The bias toward Th2 inflammation and autoantibodies derived from B cells, histamine expressed by basophils, and initiation of the extrinsic coagulation pathway by eosinophils or monocytes exerts powerful modulatory influences on mast cells. Cell-to-cell interactions between mast cells and eosinophils/T cells also are regulators of their function and may involve CSU’s pathomechanism. This review summarizes up-to-date knowledge regarding the crosstalk between mast cells and other immune cells, providing the impetus to develop new research concepts and treatment strategies for CSU.

Global Classification of Mast Cell Activation Disorders: An ICD-10-CM–Adjusted Proposal of the ECNM-AIM Consortium

Mast cell activation (MCA) is common and occurs in a number of pathologic conditions, including IgE-dependent and independent allergic reactions, atopic disorders, autoimmune processes, and mastocytosis. In a subset of patients, no underlying disease and no known trigger of MCA are found. When the symptoms are severe, systemic, and recurrent, and accompanied by a diagnostic increase in the serum tryptase level or other mast cell mediators, an MCA syndrome (MCAS) may be diagnosed. In these patients, the symptoms typically respond to drugs suppressing MCA, mediator production in mast cells, or mediator effects. In each case, diagnostic consensus criteria must be fulfilled to diagnose MCAS. In other patients, MCA may be local, less severe, or less acute, or may be suspected but not confirmed, so that the diagnostic criteria of MCAS are not fulfilled. In these patients, it may be difficult to prove MCA, for example, by measuring multiple mast cell mediators or basophil activation, the latter as a surrogate of IgE-dependent hypersensitivity. However, validated diagnostic criteria for implicating suspected MCA behind such conditions are lacking, even if some of these conditions have recently been assigned to an International Classification of Diseases-10-Clinical Modification code (ICD-10-CM). In this article, we discuss diagnostic features and criteria and propose a ICD-10-CM-adjusted classification for disorders associated with MCA, herein referred to as MCA disorders (MCADs), with special emphasis on the delineation between confirmed MCAS, MCAD not fulfilling MCAS criteria, and suspected MCAD that is not present. In addition, we discuss the discrimination between overt MCAD and predisposing conditions, such as atopic states, mastocytosis, and hereditary alpha tryptasemia.

Differential mast cell mediators in systemic mastocytosis and hereditary α-tryptasemia

Patients with systemic mastocytosis often have symptoms of mast cell activation, which is associated with elevated levels of urinary mast cell mediator metabolites. Patients with hereditary α-tryptasemia (HαT) may present with symptoms of mast cell activation. Whether levels of mast cell mediators are elevated in this patient population is not known. The purpose of this study was to determine whether patients with HαT and symptoms of mast cell activation have elevated levels of urinary mediators and compare the levels with those in patients with systemic mastocytosis. We retrospectively analyzed mast cell mediators in 63 patients with a confirmed diagnosis of HαT, 20 patients with a confirmed diagnosis of indolent systemic mastocytosis (ISM), and 23 healthy controls. All patients were referred to the Brigham and Women's Hospital Mastocytosis Center or the Mayo Clinic for evaluation of mast cell activation disorders. Our population was predominantly female (85.7%) with an average age of 53.8 years. The average baseline serum tryptase level was significantly higher in patients with ISM than in those with HαT (65.9 vs 19.3 ng/mL [P&lt; .01]). When compared with patients with HαT, those with ISM had statistically significant increases in their levels of urinary N-methylhistamine (P&lt; .01) and 2,3-dinor-11β-prostaglandin F2α (P&lt; .05). Patients with symptomatic HαT do not have elevations of mast cell urinary metabolites, suggesting that granule- and membrane-derived mediators may not drive symptoms in HαT.

The Antifibrotic and the Anticarcinogenic Activity of Capsaicin in Hot Chili Pepper in Relation to Oral Submucous Fibrosis

A burning sensation on eating spicy foods purportedly supports the role of capsaicin, an active component of chili peppers, in the etiology of oral submucous fibrosis (OSF). Although the mast cell mediators and activated P2X receptors induce a constant burning sensation through an ATP-dependent mechanism, it is the activation of the transient receptor potential vanilloid 1 (TRPV-1) receptor by capsaicin that aggravates it. The molecular basis for the burning pain in OSF is thus attributable to the activation of TRPV1. There is overwhelming evidence that confirms capsaicin has more of a protective role in attenuating fibrosis and is potentially therapeutic in reversing conditions linked to collagen accumulation. The activation of TRPV-1 by capsaicin increases intracellular calcium ([Ca2+]i), upregulates AMP-activated protein kinase (AMPK) and Sirtuin-1 (SIRT-1), to enrich endothelium-dependent vasodilation via endothelial nitric oxide synthase (eNOS). The induction of vasodilation induces antifibrotic effects by alleviating hypoxia. The antifibrotic effects of capsaicin are mediated through the upregulation of antioxidant enzymes, downregulation of inflammatory genes and suppression of new collagen fibril formation. Capsaicin also demonstrates an anticarcinogenic effect by upregulating the cytotoxic T cells and downregulating regulatory T cells through the inhibition of angiogenesis and promotion of apoptosis. Judicious administration of capsaicin with an appropriate delivery mechanism may have therapeutic benefits in reducing pain sensation, rendering antifibrotic effects, and preventing the malignant transformation of OSF. This paper provides an overview of the molecular basis of capsaicin and its therapeutic application as an antifibrotic and anticarcinogenic agent for the treatment of OSF.

Loss of isoprenylation significantly reduces IgE mediated mast cell activation

Abstract Allergic disease is the 6th leading cause of chronic illness in the US and accounts for billions of dollars in healthcare costs annually. Mast cells are tissue resident innate immune cells linked to allergic disease and activated by IgE and other ligands. Upon activation they release histamine, cytokines, chemokines, proteases, and lipid mediators evoking allergic symptoms. New ways of targeting mast cells could greatly benefit allergic disease therapy. Previous findings showed repurposing of statin drugs, such as Fluvastatin, reduced allergic symptoms in vitro and in vivo. We found that Fluvastatin suppresses IgE-mediated mast cell activation by inhibiting isoprenylation of proteins. However, statin effects were dependent on genetic background. To avert genetic background dependency, we tested the hypothesis that a dual farnesyl and geranylgeranyl transferase inhibitor (FGTI 2734) would suppress allergic disease withoutgenetic background limitations. We show that FGTI 2734 reduced IgE-mediated degranulation and cytokine production by bone marrow derived mast cells from multiple genetic backgrounds. Similarly, FGTI 2734 also suppressed IgE-mediated anaphylaxis on multiple genetic backgrounds. These in vivo effects extended to an allergic asthma model, in which FGTI 2734 inhibited pulmonary inflammation. Finally, we show that FGTI-2734 can significantly reduce IgE-induced cytokine production from human skin mast cells. These data show that dual farnesyl and geranylgeranyl transferase inhibitors may be an effective therapeutic treatment for mast cell-associated diseases. Supported by NIH (1RO1AI101153)

Tyrosine kinase inhibitors for the treatment of indolent systemic mastocytosis: Are we there yet?

Indolent systemic mastocytosis (ISM) is the most prevalent form of systemic mastocytosis. Many patients with ISM suffer from mast cell (MC) mediator-related symptoms. In a small number of patients, hematologic progression is seen in the follow-up. In some patients with ISM, symptoms arising from MC-derived mediators including gastrointestinal symptoms, anaphylaxis, and neuropsychiatric symptoms are kept under control with conventional mediator-targeting drugs or MC-stabilizing agents. However, in a substantial number of patients, the symptoms are refractory to such conventional therapy. For these patients, novel drugs and targeted approaches are considered. One reasonable approach may be to apply tyrosine kinase inhibitors directed against KIT and other key kinase targets expressed in neoplastic MCs in ISM. Because MCs in more than 90% of all patients with typical ISM display the KIT D816V mutant receptor, clinically effective KIT-targeting drugs have to be active against this mutant form of KIT. The 2 such most effective and well-studied agents currently available are midostaurin and avapritinib. Other KIT-targeting drugs, such as imatinib or masitinib, are less effective or even noneffective against KIT D816V and are thus recommended for use only in patients with other KIT mutant forms (noncodon 816 mutations) or with wild-type KIT. In the present article, we review the current state in the treatment of ISM with tyrosine kinase inhibitors, with special emphasis on treatment responses and potential adverse effects. In fact, all of these agents also have unique and common adverse effects, and their use to treat patients with ISM should be balanced against their toxicity and short- and long-term safety.

Systemic mast cell activation disease variants and certain genetically determined comorbidities may be consequences of a common underlying epigenetic disease

The available research data about mast cell activation disease (MCAD, a common disease with prevalence estimated at 17–20%) suggest it may be rooted in an unnamed transgenerationally transmittable epigenetic disease. As a result, somatic and germline mutations in a variety of genes occur which finally manifest in MCAD and its comorbidities. The combinatorial calculated number of possible combinations of such genetic alterations in mast cells results in a unique mutational pattern or profile in each patient, inducing a unique pattern of aberrant mast cell mediator production and release. Therefore, treatment must be guided by the individual’s clinical symptoms. The number of generations which the unnamed underlying epigenetic disease will affect by transgenerational transmission cannot be predicted because of insufficient knowledge about the causative processes driving this transgenerational epigenetic disease. However, in contrast to genetic diseases, epigenetic diseases are, in principle, reversible, such that individual MCAD might be able to be induced into remission, perhaps even cured, by drugs targeting the epigenome. However, new epigenomic drugs with much better risk–benefit ratios than existing epigenomic drugs are needed. Since there is currently at best only a vague conception of the processes driving transgenerational transmission, cessation and, thus, remission or cure of the epigenetic disease likely will not be inducible by drugs in the near future. The presented novel concept of MCAD being rooted in an unnamed epigenetic disease has impact on research, diagnosis and treatment of MCAD.

Human Tumor Targeted Cytotoxic Mast Cells for Cancer Immunotherapy

The diversity of autologous cells being used and investigated for cancer therapy continues to increase. Mast cells (MCs) are tissue cells that contain a unique set of anti-cancer mediators and are found in and around tumors. We sought to exploit the anti-tumor mediators in MC granules to selectively target them to tumor cells using tumor specific immunoglobin E (IgE) and controllably trigger release of anti-tumor mediators upon tumor cell engagement. We used a human HER2/neu-specific IgE to arm human MCs through the high affinity IgE receptor (FcεRI). The ability of MCs to bind to and induce apoptosis of HER2/neu-positive cancer cells in vitro and in vivo was assessed. The interactions between MCs and cancer cells were investigated in real time using confocal microscopy. The mechanism of action using cytotoxic MCs was examined using gene array profiling. Genetically manipulating autologous MC to assess the effects of MC-specific mediators have on apoptosis of tumor cells was developed using siRNA. We found that HER2/neu tumor-specific IgE-sensitized MCs bound, penetrated, and killed HER2/neu-positive tumor masses in vitro. Tunneling nanotubes formed between MCs and tumor cells are described that parallel tumor cell apoptosis. In solid tumor, human breast cancer (BC) xenograft mouse models, infusion of HER2/neu IgE-sensitized human MCs co-localized to BC cells, decreased tumor burden, and prolonged overall survival without indications of toxicity. Gene microarray of tumor cells suggests a dependence on TNF and TGFβ signaling pathways leading to apoptosis. Knocking down MC-released tryptase did not affect apoptosis of cancer cells. These studies suggest MCs can be polarized from Type I hypersensitivity-mediating cells to cytotoxic cells that selectively target tumor cells and specifically triggered to release anti-tumor mediators. A strategy to investigate which MC mediators are responsible for the observed tumor killing is described so that rational decisions can be made in the future when selecting which mediators to target for deletion or those that could further polarize them to cytotoxic MC by adding other known anti-tumor agents. Using autologous human MC may provide further options for cancer therapeutics that offers a unique anti-cancer mechanism of action using tumor targeted IgE’s.

Cutaneous Mastocytosis in an 8-year-old child: Case Report and Review of the Literature

Mastocytosis is a clinical condition occurring from birth to adulthood and may involve mainly the skin and/ or many organs such as the liver, bone marrow, spleen and lymph nodes. The condition has a bimodal distribution presenting in children from birth to 2 years of age and in patients older than 15. In adult patients may or may not have cutaneous involvement. In cutaneous mastocytosis the mast cells infiltrate mostly the skin but may be associated with systemic symptoms due to mast cell mediators release. In children, the disease manifests with one or more tan to red-brown papules or plaques (urticaria pigmentosa). Patients with mastocytosis may be asymptomatic or have symptoms due to mast cells degranulation – itch, flush, headache, syncope, gastrointestinal complaints of abdominal pain and diarrhea. A pathognomic sign for the disease is Darier`s sign where stroking of the skin lesions provokes pronounced urtication due to mast cells degranulation. Diagnosis of cutaneous mastocytosis is based on clinical morphology of skin lesions, positive Darier`s sign and histological skin lesions stained for tryptase and/or CD117. Therapeutic management involves avoiding triggers, H1-/H2- receptor blockers and symptomatic medications. All patients with cutaneous mastocytosis require follow-up examinations. Herein, a clinical case of an 8-year-old male patient with cutaneous mastocytosis is presented. An update comprehensive review of literature focusing on clinical findings, diagnosis and modern therapeutic modalities is highlighted.