A PTP1B-Cdk3 Signaling Axis Promotes Cell Cycle Progression of Human Glioblastoma Cells through an Rb-E2F Dependent Pathway.

PTP1B plays a key role in developing different types of cancer. However, the molecular mechanism underlying this effect is unclear. To identify molecular targets of PTP1B that mediate its role in tumorigenesis, we undertook a SILAC-based phosphoproteomic approach, which allowed us to identify Cdk3 as a novel PTP1B substrate. Substrate trapping experiments and docking studies revealed stable interactions between the PTP1B catalytic domain and Cdk3. In addition, we observed that PTP1B dephosphorylates Cdk3 at tyrosine residue 15 in vitro and interacts with it in human glioblastoma cells. Next, we found that pharmacological inhibition of PTP1B or its depletion with siRNA leads to cell cycle arrest with diminished activity of Cdk3, hypophosphorylation of Rb, and the downregulation of E2F target genes Cdk1, Cyclin A, and Cyclin E1. Finally, we observed that the expression of a constitutively active Cdk3 mutant bypasses the requirement of PTP1B for cell cycle progression and expression of E2F target genes. These data delineate a novel signaling pathway from PTP1B to Cdk3 required for efficient cell cycle progression in an Rb-E2F dependent manner in human GB cells.

Microencapsulation of Propolis and Honey Using Mixtures of Maltodextrin/Tara Gum and Modified Native Potato Starch/Tara Gum.

Ethanolic extracts of propolis and bee honey contain substances beneficial to human health. Mixtures of wall materials were compared in spray-drying microencapsulation of ethanolic extracts of propolis and bee honey rich in bioactive compounds. Maltodextrin and tara gum were used to obtain microencapsulates A, and modified native potato starch and tara gum were used for microencapsulates B. High values of phenolic compounds, flavonoids, and antioxidant capacity were obtained in microcapsules A and B, and the results obtained in terms of encapsulation efficiency, yield, hygroscopicity, solubility, moisture, Aw, bulk density, and color were typical of the spray-drying process. On the other hand, spherical and elliptical microparticles of sizes between 7.83 and 53.7 µm with light and medium stability were observed. Thermogravimetric properties were similar in both microencapsulates; total organic carbon, SEM-EDS, and FTIR analyses corroborated the encapsulation. X-ray diffractogram exhibited amorphous structures, and the release kinetics of phenolic compounds presented high values from 8.13 to 12.58 mg GAE/g between 7 and 13 h. Finally, modified potato starch is a better encapsulant than maltodextrin because it has better core protection and controlled release of the encapsulated bioactive compounds.

Bioactive Compounds and Sensory Analysis of Freeze-Dried Prickly Pear Fruits from an Inter-Andean Valley in Peru.

Prickly pear fruits are seasonal and have shades ranging from pale green to deep purple. Their pigments are associated with bioactive compounds, being sensitive to thermal transformation processes for their conservation. The objective of this research was to evaluate the bioactive compounds and the sensory analysis of freeze-dried prickly pear fruits from an inter-Andean valley in Peru. The prickly pear fruits of the morada, anaranjada, and blanca ecotypes came from an inter-Andean valley in Peru at 2972 m altitude. The sliced fruits were freeze-dried at -40 °C and 0.25 mTorr, and the total polyphenol content (TPC), vitamin C, and antioxidant activity (AA) were determined, as well as the color L* a* b*, color index (CI*), FTIR spectra, and mineral content. In the same way, sensory analysis of preferences with nine scales was applied. It was observed that in the freeze-dried fruits, TPC, AA, and vitamin C increased significantly (p-value < 0.05), and their corresponding functional groups increased in intensity in their corresponding FTIR spectra; furthermore, trace elements such as Cu, Fe, Se, Zn, Si, and Mn were identified. On the other hand, freeze-drying provided deeper colors to the fruits, which most panelists said they "very much liked" during the sensory analysis, although the texture was not very well accepted, with most panelists reporting being "indifferent" towards it. The freeze-drying technique allows the bioactive and sensory attributes of prickly pear fruits from inter-Andean valleys to be preserved, making it a potential fruit for export and conservation due to its seasonality.

Myosin 1g as a high-risk biomarker in a pediatric patient with lineage switch from acute lymphoblastic leukemia to myeloid phenotype.

BACKGROUND: Myosin 1g (Myo1g) has recently been identified as a potential diagnostic biomarker in childhood acute lymphocytic leukemia (ALL). CASE REPORT: We describe the case of a 1-year-old Mexican female patient. Although initially studied for hepatomegaly, an infectious or genetic etiology was excluded. Liver biopsy showed infiltration by neoplastic B-cell precursors (BCPs), and bone marrow (BM) aspirate showed 14.5% of BCPs. In a joint session of the oncology, hematology, and pathology departments, low-risk (LR) BCP-ALL of hepatic origin with aberrant myeloid markers was diagnosed. Although treatment was initiated, the patient presented early with BM relapse. Modest overexpression of Myo1g was observed from the onset. However, at the end of the steroid window, expression increased significantly and remained elevated during this first relapse to BM. The parents refused hematopoietic stem cell transplantation, but she continued chemotherapy. After a second BM relapse at 5 years of age, the phenotype switched to myeloid. Her parents then opted for palliative care, and the patient died two months later at home. CONCLUSIONS: This case shows the potential use of Myo1g in clinical practice as a high-risk indicator. Myo1g monitoring may reveal a high risk and relapse trend, even when typical parameter values are not altered: Myo1g could be used to classify patients from low to high risk from diagnosis, allowing patients to promptly receive the best treatment and potentially modifying prognosis and survival.

INTRODUCCIÓN: Recientemente se ha identificado a miosina 1g (Myo1g) como un potencial biomarcador de diagnóstico en la leucemia linfoblástica aguda (LLA) infantil. CASO CLÍNICO: Se describe el caso de una paciente mexicana de 1 año de edad. Aunque inicialmente se estudió por hepatomegalia, se descartó una etiología infecciosa o genética. La biopsia hepática mostró infiltración por precursores de células B neoplásicas (PCB) y un aspirado de médula ósea (MO) mostró 14.5% de PCB. En una sesión conjunta de los departamentos de oncología, hematología y patología, se diagnosticó PCB-LLA de bajo riesgo de origen hepático con marcadores mieloides aberrantes. Aunque se inició tratamiento, la paciente presentó tempranamente recaída de MO. Se observó una modesta sobreexpresión de Myo1g. Sin embargo, al final de la ventana de esteroides, la expresión aumentó considerablemente y permaneció elevada durante esta primera recaída a MO. El trasplante de células madre hematopoyéticas fue rechazado por los padres, pero se continuó con la quimioterapia. Tras una segunda recaída de MO a los 5 años, el fenotipo cambió a mieloide. Sus padres optaron entonces por cuidados paliativos y la paciente falleció dos meses después en su domicilio. CONCLUSIONES: Este caso muestra el potencial uso de Myo1g como indicador de alto riesgo en la práctica clínica. El seguimiento de Myo1g puede revelar una tendencia de alto riesgo y recaídas, incluso cuando los valores de los parámetros rutinarios son aparentemente normales; Myo1g podría utilizarse para clasificar a los pacientes de bajo a alto riesgo desde el diagnóstico, lo que permitiría que los pacientes reciban el mejor tratamiento de manera oportuna, modificando potencialmente el pronóstico y la supervivencia.

Myosin 1g as a high-risk biomarker in a pediatric patient with lineage switch from acute lymphoblastic leukemia to myeloid phenotype / Miosina 1g como un marcador de alto riesgo en una paciente pediátrica con cambio de linaje de leucemia linfoblástica aguda a fenotipo mieloide

Abstract Background: Myosin 1g (Myo1g) has recently been identified as a potential diagnostic biomarker in childhood acute lymphocytic leukemia (ALL). Case report: We describe the case of a 1-year-old Mexican female patient. Although initially studied for hepatomegaly, an infectious or genetic etiology was excluded. Liver biopsy showed infiltration by neoplastic B-cell precursors (BCPs), and bone marrow (BM) aspirate showed 14.5% of BCPs. In a joint session of the oncology, hematology, and pathology departments, low-risk (LR) BCP-ALL of hepatic origin with aberrant myeloid markers was diagnosed. Although treatment was initiated, the patient presented early with BM relapse. Modest overexpression of Myo1g was observed from the onset. However, at the end of the steroid window, expression increased significantly and remained elevated during this first relapse to BM. The parents refused hematopoietic stem cell transplantation, but she continued chemotherapy. After a second BM relapse at 5 years of age, the phenotype switched to myeloid. Her parents then opted for palliative care, and the patient died two months later at home. Conclusions: This case shows the potential use of Myo1g in clinical practice as a high-risk indicator. Myo1g monitoring may reveal a high risk and relapse trend, even when typical parameter values are not altered: Myo1g could be used to classify patients from low to high risk from diagnosis, allowing patients to promptly receive the best treatment and potentially modifying prognosis and survival.

Resumen Introducción: Recientemente se ha identificado a miosina 1g (Myo1g) como un potencial biomarcador de diagnóstico en la leucemia linfoblástica aguda (LLA) infantil. Caso clínico: Se describe el caso de una paciente mexicana de 1 año de edad. Aunque inicialmente se estudió por hepatomegalia, se descartó una etiología infecciosa o genética. La biopsia hepática mostró infiltración por precursores de células B neoplásicas (PCB) y un aspirado de médula ósea (MO) mostró 14.5% de PCB. En una sesión conjunta de los departamentos de oncología, hematología y patología, se diagnosticó PCB-LLA de bajo riesgo de origen hepático con marcadores mieloides aberrantes. Aunque se inició tratamiento, la paciente presentó tempranamente recaída de MO. Se observó una modesta sobreexpresión de Myo1g. Sin embargo, al final de la ventana de esteroides, la expresión aumentó considerablemente y permaneció elevada durante esta primera recaída a MO. El trasplante de células madre hematopoyéticas fue rechazado por los padres, pero se continuó con la quimioterapia. Tras una segunda recaída de MO a los 5 años, el fenotipo cambió a mieloide. Sus padres optaron entonces por cuidados paliativos y la paciente falleció dos meses después en su domicilio. Conclusiones: Este caso muestra el potencial uso de Myo1g como indicador de alto riesgo en la práctica clínica. El seguimiento de Myo1g puede revelar una tendencia de alto riesgo y recaídas, incluso cuando los valores de los parámetros rutinarios son aparentemente normales; Myo1g podría utilizarse para clasificar a los pacientes de bajo a alto riesgo desde el diagnóstico, lo que permitiría que los pacientes reciban el mejor tratamiento de manera oportuna, modificando potencialmente el pronóstico y la supervivencia.

Immunoproteomics of cow's milk allergy in Mexican pediatric patients.

Immunological mechanisms of non-IgE-mediated cow's milk protein allergy (CMPA) are not well understood. Such a circumstance requires attention with the aim of discovering new biomarkers that could lead to better diagnostic assays for early treatment. Here, we sought both to investigate the mechanism that underlies non-IgE-mediated CMPA and to identify cow's milk immunoreactive proteins in a Mexican pediatric patient group (n = 34). Hence, we determined the IgE and IgG1-4 subclass antibody levels against cow's milk proteins (CMP) by ELISA. Then, we performed 2D-Immunoblots using as first antibody immunoglobulins in the patients'serum that bound specifically against CMP together with CMP enrichment by ion-exchange chromatography. Immunoreactive proteins were identified by mass spectrometry-based proteomics. The serological test confirmed absence of specific IgE in the CMPA patients but showed significant increase in antigen-specific IgG1. Additionally, we identified 11 proteins that specifically bound to IgG1. We conclude that the detection of specific IgG1 together with an immunoproteomics approach is highly relevant to the understanding of CMPA's physiopathology and as a possible aid in making a prognosis since current evidence indicates IgG1 occurrence as an early signal of potential risk toward development of IgE-mediated food allergy. SIGNIFICANCE: Allergies are one of the most studied topics in the field of public health and novel protein allergens are found each year. Discovery of new principal and regional allergens has remarkable repercussions in precise molecular diagnostics, prognostics, and more specific immunotherapies. In this context, specific IgE is widely known to mediate physiopathology; however, allergies whose mechanism does not involve this immunoglobulin are poorly understood although their incidence has increased. Therefore, accurate diagnosis and adequate treatment are delayed with significant consequences on the health of pediatric patients. The study of type and subtypes of immunoglobulins associated with the immunoreactivity of cow's milk proteins together with an immunoproteomics approach allows better comprehension of physiopathology, brings the opportunity to discover new potential cow's milk protein allergens and may help in prognosis prediction (IgG1 occurrence as an early signal of possible risk toward development of IgE-mediated food allergy).

Effect of the Addition of Corn Husk Cellulose Nanocrystals in the Development of a Novel Edible Film.

The cellulose from agroindustrial waste can be treated and converted into nanocrystals or nanofibers. It could be used to produce biodegradable and edible films, contributing to the circular economy and being environmentally friendly. This research aimed to develop an edible film elaborated with activated cellulose nanocrystals, native potato starch, and glycerin. The activated cellulose nanocrystals were obtained by basic/acid digestion and esterification with citric acid from corn husks. The starch was extracted from the native potato cultivated at 3500 m of altitude. Four film formulations were elaborated with potato starch (2.6 to 4.4%), cellulose nanocrystals (0.0 to 0.12%), and glycerin (3.0 to 4.2%), by thermoforming at 60 °C. It was observed that the cellulose nanocrystals reported an average size of 676.0 nm. The films mainly present hydroxyl, carbonyl, and carboxyl groups that stabilize the polymeric matrix. It was observed that the addition of cellulose nanocrystals in the films significantly increased (p-value < 0.05) water activity (0.409 to 0.447), whiteness index (96.92 to 97.27), and organic carbon content. In opposition to gelatinization temperature (156.7 to 150.1 °C), transparency (6.69 to 6.17), resistance to traction (22.29 to 14.33 N/mm), and solubility in acidic, basic, ethanol, and water media decreased. However, no significant differences were observed in the thermal decomposition of the films evaluated through TGA analysis. The addition of cellulose nanocrystals in the films gives it good mechanical and thermal resistance qualities, with low solubility, making it a potential food-coating material.

IL-36γ is secreted through an unconventional pathway using the Gasdermin D and P2X7R membrane pores.

Mucosal innate immunity functions as the first line of defense against invading pathogens. Members of the IL-1 family are key cytokines upregulated in the inflamed mucosa. Inflammatory cytokines are regulated by limiting their function and availability through their activation and secretion mechanisms. IL-1 cytokines secretion is affected by the lack of a signal peptide on their sequence, which prevents them from accessing the conventional protein secretion pathway; thus, they use unconventional protein secretion pathways. Here we show in mouse macrophages that LPS/ATP stimulation induces cytokine relocalization to the plasma membrane, and conventional secretion blockade using monensin or Brefeldin A triggers no IL-36γ accumulation within the cell. In silico modeling indicates IL-36γ can pass through both the P2X7R and Gasdermin D pores, and both IL-36γ, P2X7R and Gasdermin D mRNA are upregulated in inflammation; further, experimental blockade of these receptors' limits IL-36γ release. Our results demonstrate that IL-36γ is secreted mainly by an unconventional pathway through membrane pores formed by P2X7R and Gasdermin D.

Clinical features and severe acute respiratory syndrome-coronavirus-2 structural protein-based serology of Mexican children and adolescents with coronavirus disease 2019.

Severe acute respiratory syndrome (SARS)-coronavirus (CoV)-2 infection in children and adolescents primarily causes mild or asymptomatic coronavirus disease 2019 (COVID-19), and severe illness is mainly associated with comorbidities. However, the worldwide prevalence of COVID-19 in this population is only 1%-2%. In Mexico, the prevalence of COVID-19 in children has increased to 10%. As serology-based studies are scarce, we analyzed the clinical features and serological response (SARS-CoV-2 structural proteins) of children and adolescents who visited the Hospital Infantil de México Federico Gómez (October 2020-March 2021). The majority were 9-year-old children without comorbidities who were treated as outpatients and had mild-to-moderate illness. Children aged 6-10 years and adolescents aged 11-15 years had the maximum number of symptoms, including those with obesity. Nevertheless, children with comorbidities such as immunosuppression, leukemia, and obesity exhibited the lowest antibody response, whereas those aged 1-5 years with heart disease had the highest levels of antibodies. The SARS-CoV-2 spike receptor-binding domain-localized peptides and M and E proteins had the best antibody response. In conclusion, Mexican children and adolescents with COVID-19 represent a heterogeneous population, and comorbidities play an important role in the antibody response against SARS-CoV-2 infection.

Effect of the Application of a Coating Native Potato Starch/Nopal Mucilage/Pectin on Physicochemical and Physiological Properties during Storage of Fuerte and Hass Avocado (Persea americana).

The avocado fruit is an agro-industrial product with high export demand in Peru due to its sensory and nutritional qualities, which can be affected during storage. The study aimed to evaluate the effect of the application of a coating formulated with potato starch (Solanum tuberosum ssp andigena), nopal mucilage (Opuntia ficus indica), and pectin on the physicochemical and physiological properties during the storage of Fuerte and Hass avocados. Samples were taken in their harvest state from the plantation in "Occobamba", which is cultivated by the Avocado Producers Association in Chincheros, Apurímac, Peru. Physicochemical properties (titratable acidity, pH, total soluble solids) and physiological properties (weight loss, firmness, and color L* a* b*) were determined during 20 days of storage at 20 °C. The elaborated films present high transparency and low aw values. In the coated avocado of the Hass and Fuerte varieties, acidity and total soluble solids decreased significantly (p-value < 0.05) during the storage time. Weight loss and firmness of coated fruits decrease to a lesser extent. Luminosity L*, color index, and color variation showed better attributes for the coated samples. The use of coatings made with potato starch, nopal mucilage, and pectin allows the physicochemical and physiological properties of avocado fruits to be maintained for a longer time during storage.

Sex-dependent effect of aging on calcium signaling and expression of TRPM2 and CRAC channels in human neutrophils.

The vulnerability of older adults to bacterial infections has been associated with age-related changes in neutrophils. We analyzed the consequences of aging on calcium (Ca2+) mobilization and TRPM2 and CRAC channels expression in human neutrophils. The percentages of granulocytes, mature neutrophils, and neutrophil precursors were equivalent between young and older adults. However, neutrophil chemotaxis towards IL-8, C5a, or fMLP was lower in older adults of both sexes. Interestingly, a stronger Ca2+ transient followed by an identical Ca2+ influx to IL-8 was observed in older adult females. In addition, the Ca2+ response to LPS was delayed and prolonged in neutrophils of older adult males. There was no significant difference in Ca2+ response to fMLP, C5a, or store-operated Ca2+ entry in the older adults. There were also no differences in the expression of CXCR2, CD88, FPLR1, and TLR4. Interestingly, TRPM2- and ORAI1-mRNA expression was lower in neutrophils of older adults, mainly in females. Both channels were detected intracellularly in the neutrophils. TRPM2 was in late endosomes in young adults and in lysosomes in older adult neutrophils. In summary, defective neutrophil chemotaxis in aging seemed not to stem from alterations in Ca2+ signals; nevertheless, the low TRPM2 and ORAI1 expression may affect other functions.

Detection of Myosin 1g Overexpression in Pediatric Leukemia by Novel Monoclonal Antibodies.

Myosin 1g (Myo1g) is a mechanoenzyme associated with actin filaments, expressed exclusively in hematopoietic cells, and involved in various cellular functions, including cell migration, adhesion, and membrane trafficking. Despite the importance of Myo1g in distinct functions, there is currently no monoclonal antibody (mAb) against Myo1g. mAbs are helpful tools for the detection of specific antigens in tumor cells and other tissues. The development of mAbs against targeted dysregulated molecules in cancer cells remains a crucial tool for aiding in the diagnosis and the treatment of patients. Using hybridoma technology, we generated a panel of hybridomas specific for Myo1g. ELISA, immunofluorescence, and Western blot assay results revealed the recognition of Myo1g by these novel monoclonal antibodies in normal and transformed T and B cells. Here, we report the development and application of new monoclonal antibodies against Myo1g for their potential use to detect its overexpression in acute lymphoblastic leukemia (ALL) patients.

Transcriptional Regulation of Yin-Yang 1 Expression through the Hypoxia Inducible Factor-1 in Pediatric Acute Lymphoblastic Leukemia.

Yin-Yang transcription factor 1 (YY1) is involved in tumor progression, metastasis and has been shown to be elevated in different cancers, including leukemia. The regulatory mechanism underlying YY1 expression in leukemia is still not understood. Bioinformatics analysis reveal three Hypoxia-inducible factor 1-alpha (HIF-1α) putative binding sites in the YY1 promoter region. The regulation of YY1 by HIF-1α in leukemia was analyzed. Mutation of the putative YY1 binding sites in a reporter system containing the HIF-1α promoter region and CHIP analysis confirmed that these sites are important for YY1 regulation. Leukemia cell lines showed that both proteins HIF-1α and YY1 are co-expressed under hypoxia. In addition, the expression of mRNA of YY1 was increased after 3 h of hypoxia conditions and affect several target genes expression. In contrast, chemical inhibition of HIF-1α induces downregulation of YY1 and sensitizes cells to chemotherapeutic drugs. The clinical implications of HIF-1α in the regulation of YY1 were investigated by evaluation of expression of HIF-1α and YY1 in 108 peripheral blood samples and by RT-PCR in 46 bone marrow samples of patients with pediatric acute lymphoblastic leukemia (ALL). We found that the expression of HIF-1α positively correlates with YY1 expression in those patients. This is consistent with bioinformatic analyses of several databases. Our findings demonstrate for the first time that YY1 can be transcriptionally regulated by HIF-1α, and a correlation between HIF-1α expression and YY1 was found in ALL clinical samples. Hence, HIF-1α and YY1 may be possible therapeutic target and/or biomarkers of ALL.

Class I Myosins, molecular motors involved in cell migration and cancer.

Class I Myosins are a subfamily of motor proteins with ATPase activity and a characteristic structure conserved in all myosins: A N-Terminal Motor Domain, a central Neck and a C terminal Tail domain. Humans have eight genes for these myosins. Class I Myosins have different functions: regulate membrane tension, participate in endocytosis, exocytosis, intracellular trafficking and cell migration. Cell migration is influenced by many cellular components including motor proteins, like myosins. Recently has been reported that changes in myosin expression have an impact on the migration of cancer cells, the formation of infiltrates and metastasis. We propose that class I myosins might be potential markers for future diagnostic, prognostic or even as therapeutic targets in leukemia and other cancers.Abbreviations: Myo1g: Myosin 1g; ALL: Acute Lymphoblastic Leukemia, TH1: Tail Homology 1; TH2: Tail Homology 2; TH3: Tail Homology 3.

Aging does not affect calcium response to CCL2 and LPS in human monocytes.

Monocytes play important roles in anti-microbial and anti-viral responses and chronic inflammatory diseases. Monocytes' functions are altered by aging. We investigated age-changes in calcium (Ca2+) response to CCL2 and LPS in human monocytes. CCL2 and LPS induced a slow increase of the cytosolic Ca2+ level, with a maximum response at ∼360 s and ∼300 s, respectively, in monocytes of young and older adults. No difference was observed in the magnitude and in the Ca2+ kinetic with both stimuli. Furthermore, store-operated Ca2+ entry and plasma membrane expression of ORAI1 showed no difference between both groups. In summary, monocytes from older adults maintained the capacity to mobilize calcium as their counterparts in young adults suggesting that the mechanisms underlying the dysfunctions in monocytes in aging might not involve alterations in Ca2+ flow through the plasma membrane.

TBC1D10C is a cytoskeletal functional linker that modulates cell spreading and phagocytosis in macrophages.

Cell spreading and phagocytosis are notably regulated by small GTPases and GAP proteins. TBC1D10C is a dual inhibitory protein with GAP activity. In immune cells, TBC1D10C is one of the elements regulating lymphocyte activation. However, its specific role in macrophages remains unknown. Here, we show that TBC1D10C engages in functions dependent on the cytoskeleton and plasma membrane reorganization. Using ex vivo and in vitro assays, we found that elimination and overexpression of TBC1D10C modified the cytoskeletal architecture of macrophages by decreasing and increasing the spreading ability of these cells, respectively. In addition, TBC1D10C overexpression contributed to higher phagocytic activity against Burkholderia cenocepacia and to increased cell membrane tension. Furthermore, by performing in vitro and in silico analyses, we identified 27 TBC1D10C-interacting proteins, some of which were functionally classified as protein complexes involved in cytoskeletal dynamics. Interestingly, we identified one unreported TBC1D10C-intrinsically disordered region (IDR) with biological potential at the cytoskeleton level. Our results demonstrate that TBC1D10C shapes macrophage activity by inducing reorganization of the cytoskeleton-plasma membrane in cell spreading and phagocytosis. We anticipate our results will be the basis for further studies focused on TBC1D10C. For example, the specific molecular mechanism in Burkholderia cenocepacia phagocytosis and functional analysis of TBC1D10C-IDR are needed to further understand its role in health and disease.

High expression of Myosin 1g in pediatric acute lymphoblastic leukemia.

Acute Lymphoblastic Leukemia (ALL) is the most frequent cancer in pediatric population. Although the treatment has improved and almost 85% of the children are cured about 20% suffer relapse, therefore finding molecules that participate in the pathogenesis of the disease for the identification of relapse and patients at risk is an urgent unmet need. Class I myosins are molecular motors involved in membrane tension, endocytosis, phagocytosis and cell migration and recently they have been shown important for development and aggressiveness of diverse cancer types, however Myo1g an hematopoietic specific myosin has not been studied in cancer so far. We evaluated the expression of Myo1g by qRT-PCR, Immunocytochemistry and Immunofluorescence in a cohort of 133 ALL patients and correlated the expression at diagnosis and after treatment with clinical features and treatment outcomes. We found high expression levels of Myo1g in Peripheral Blood Mononuclear Cells (PBMCs) from patients with ALL at diagnosis and those levels decreased after complete remission; furthermore, we found an increase in Myo1g expression on patients with 9:22 translocation and those who relapse. This study show that Myo1g is over expressed in ALL and that may participate in the pathogenesis of the disease specially in high-risk patients.

NLRP3 Regulates IL-4 Expression in TOX+ CD4+ T Cells of Cutaneous T Cell Lymphoma to Potentially Promote Disease Progression.

In cutaneous T cell lymphoma (CTCL), a dominant Th2 profile associated with disease progression has been proposed. Moreover, although the production and regulation of IL-4 expression during the early stages of the disease may have important implications in later stages, these processes are poorly understood. Here, we demonstrate the presence of TOX+ CD4+ T cells that produce IL-4+ in early-stage skin lesions of CTCL patients and reveal a complex mechanism by which the NLRP3 receptor promotes a Th2 response by controlling IL-4 production. Unassembled NLRP3 is able to translocate to the nucleus of malignant CD4+ T cells, where it binds to the human il-4 promoter. Accordingly, IL-4 expression is decreased by knocking down and increased by promoting the nuclear localization of NLRP3. We describe a positive feedback loop in which IL-4 inhibits NLRP3 inflammasome assembly, thereby further increasing its production. IL-4 induced a potentially malignant phenotype measured based on TOX expression and proliferation. This mechanism of IL-4 regulation mediated by NLRP3 is amplified in late-stage CTCL associated with disease progression. These results indicate that NLRP3 might be a key regulator of IL-4 expression in TOX+ CD4+ T cells of CTCL patients and that this mechanism might have important implications in the progression of the disease.

Evaluation and Quantification of Micro Epithelial Gaps in the Colonic Mucosa using Immunofluorescence Staining.

Epithelial cells lining the intestinal mucosa create a physical barrier that separates the luminal content from the interstitium. Epithelial barrier impairment has been associated with the development of various pathologies such as inflammatory bowel diseases (IBD). In the inflamed mucosa, superficial erosions or micro-erosions that corrupt epithelial monolayers correspond to sites of high permeability. Several mechanisms have been implicated in the formation of micro-erosions including cell shedding and apoptosis. These micro-erosions often represent microscopic epithelial gaps randomly distributed in the colon. Visualization and quantification of those epithelial gaps has emerged as an important tool to investigate intestinal epithelial barrier function. Here, we describe a new method to visualize the specific location of where transcellular and paracellular permeability is enhanced in the inflamed colonic mucosa. In this assay, we apply a 10 kDa fluorescent dye conjugated to a lysine fixable dextran to visualize high permeability regions (HPR) in the colonic mucosa. Additional use of cell death markers revealed that HPR encompass apoptotic foci where epithelial extrusion/shedding occurs. The protocol described here provides a simple but effective approach to visualize and quantify micro-erosions in the intestine, which is a very useful tool in disease models, in which the intestinal epithelial barrier is compromised.