Anterior Mediastinal Neuroblastoma Associated with Syndrome of Inappropriate Antidiuretic Hormone Secretion: A Morphologic, Immunohistochemical, and Genetic Case Report and Review of the Literature.

We report a mediastinal neuroblastoma in an octogenarian with paraneoplastic syndrome of inappropriate antidiuretic hormone secretion (SIADH). Neuroblastomas are very rare tumors in adults, with thoracic or mediastinal locations being especially uncommon. These neoplasms have been occasionally associated with the SIADH. Given the rarity of incidence and paucity of diagnostic and outcomes data, the significance of standard neuroblastoma prognostic characteristics is unclear, and no treatment paradigms exist for these patients. Further studies are needed to inform future clinical guidelines.

Purification and Immunophenotypic Characterization of Murine Plasma Cells.

B cells are primarily known for their capacity to differentiate into antibody-secreting cells (ASCs). ASCs are usually viewed as terminally differentiated cells sharing a unique phenotype. However, it lately became evident that ASCs exist in a variety of subsets differing by their lifespan, anatomic location, and immunological function. Thus, ASCs can exist as long-lived plasma cells (LLPC) that can persist for years in a nonproliferating state within particular niches in the bone marrow (BM), or as short-lived plasma cells (SLPC) that are primarily found in secondary lymphoid organs or inflamed tissues and wane upon the termination of the associated immune response. Another layer of ASC diversity was uncovered with the discovery of their capacity to produce various pro- or anti-inflammatory cytokines. Notably, a subset of natural regulatory plasma cells characterized by the distinctive expression of the inhibitory receptor lymphocyte activation gene (LAG)-3 and a unique capacity to produce interleukin (IL)-10 upon stimulation was recently identified. Here, we describe how to immunophenotypically characterize murine plasma cells as well as how to isolate them using cell sorting, with a special focus on these recently described natural regulatory plasma cells.

Isolation and characterization of equine peripheral blood-derived multipotent mesenchymal stromal cells / Isolamento e caracterização das células mesenquimais multipotentes estromais derivadas do sangue periférico equino

The objective of the study was to isolate, cultivate and characterize equine peripheral blood-derived multipotent mesenchymal stromal cells (PbMSCs). Peripheral blood was collected, followed by the isolation of mononuclear cells using density gradient reagents, and the cultivation of adherent cells. Monoclonal mouse anti-horse CD13, mouse anti-horse CD44, and mouse anti-rat CD90 antibodies were used for the immunophenotypic characterization of the surface of the PbMSCs. These cells were also cultured in specific media for adipogenic and chondrogenic differentiation. There was no expression of the CD13 marker, but CD44 and CD90 were expressed in all of the passages tested. After 14 days of cell differentiation into adipocytes, lipid droplets were observed upon Oil Red O (ORO) staining. Twenty-one days after chondrogenic differentiation, the cells were stained with Alcian Blue. Although the technique for the isolation of these cells requires improvement, the present study demonstrates the partial characterization of PbMSCs, classifying them as a promising type of progenitor cells for use in equine cell therapy.

O objetivo deste estudo foi isolar, cultivar e caracterizar as células mesenquimais multipotentes estromais derivadas do sangue periférico (SpCTMs) equino. O sangue periférico foi coletado, seguido do isolamento das células mononucleadas utilizando o reagente de gradiente de densidade e o cultivo das células aderentes. Os anticorpos monoclonais mouse anti-horse CD13, mouse anti-horse CD44 e mouse anti-rat CD90 foram utilizados para a caracterização imunofenotípica da superfície das SpCTMs. Estas células também foram cultivadas utilizando meio de cultura específico para a diferenciação adipogênica e condrogênica. Não houve expressão do marcador CD13, mas os marcadores CD44 e CD90 foram expressos em todas as passagens testadas. Após 14 dias da diferenciação das células em adipócitos, gotículas de lipídeos foram observados através da coloração com Oil Red O. Vinte e um dias após a diferenciação condrogênica, as células foram coradas com o Alcian Blue. Embora a técnica de isolamento destas células necessite ser otimizada, o presente estudo demonstra a caracterização parcial das SpCTMs, classificando-as como um tipo de células progenitoras promissoras para o uso na terapia celular em equinos.

Characterization of mesenchymal stem cells derived from equine adipose tissue / Caracterização das células tronco mesenquimais derivadas do tecido adiposo equino

Stem cell therapy has shown promising results in tendinitis and osteoarthritis in equine medicine. The purpose of this work was to characterize the adipose-derived mesenchymal stem cells (AdMSCs) in horses through (1) the assessment of the capacity of progenitor cells to perform adipogenic, osteogenic and chondrogenic differentiation; and (2) flow cytometry analysis using the stemness related markers: CD44, CD90, CD105 and MHC Class II. Five mixed-breed horses, aged 2-4 years-old were used to collect adipose tissue from the base of the tail. After isolation and culture of AdMSCs, immunophenotypic characterization was performed through flow cytometry. There was a high expression of CD44, CD90 and CD105, and no expression of MHC Class II markers. The tri-lineage differentiation was confirmed by specific staining: adipogenic (Oil Red O), osteogenic (Alizarin Red), and chondrogenic (Alcian Blue). The equine AdMSCs are a promising type of adult progenitor cell for tissue engineering in veterinary medicine.

O uso de células tronco tem demonstrado resultados promissores na terapia da tendinite e osteoartrite na medicina equina. O objetivo deste trabalho foi caracterizar as células tronco mesenquimais derivadas do tecido adiposo (AdCTMs) em cavalos através da (1) avaliação da capacidade das células progenitoras para realizar a diferenciação adipogênica, osteogênica e condrogênica; e (2) através da análise por citometria de fluxo, utilizando os marcadores stemness relacionados: CD44, CD90, CD105 e MHC de Classe II. Cinco cavalos sem raça definida, de 2 a 4 anos de idade foram utilizados para a coleta do tecido adiposo da base da cauda. Após o isolamento e cultivo das AdCTMs, a caracterização imunofenotípica foi realizada pela citometria de fluxo. Houve alta expressão dos marcadores CD44, CD90 e CD105, e não houve expressão do MHC Classe II. A diferenciação foi confirmada pela coloração específica: adipogênica (Oil Red O), osteogênico (Alizarin Red), e condrogênico (Alcian Blue). As AdCTMs são um tipo promissor de células progenitoras adulta para a engenharia tecidual na medicina veterinária.