Investigating the role of Prefrontal Neurons in cognitive tasks through Fiber Photometry and Adapted Barnes Maze Protocols

The medial prefrontal cortex (mPFC) is essential in the execution of cognitive tasks, however very little is known on how these neurons are modulated during specific tasks and which subtype of neurons are responsible for so. Therego, with the intention of addressing this issue, we recorded mPFC gabaergic and glutamatergic activation patterns through fiber photometry (FIP) in mice, while simultaneously performing the Barnes Maze (BM) cognitive task (4 day behavioral trial). In addition, an altered structural and procedural protocol for BM was validated in this study due to necessary modifications allowing FIP and BM to happen simultaneously. A successful protocol validation was followed by our preliminary results, which showed that both glutamatergic and gabaergic neurons presented significant change in activation intensity and number of events in specific contexts throughout the task days. In addition, when stratified and crossed with BM performance parameters, such as latency to complete tasks and adopted strategy, glutamatergic and gabaergic neurons presented a significant decline in both activation patterns and number of activation events throughout the days. This data suggest not only an important role of glutamatergic and gabaergic mPFC neurons in learning, memory and decision making, but also that activation patterns of each of these groups may serve as markers for cognitive progression and/or dysfunction. KEY-WORDS: Memory, Learning, Decision Making, Medial Prefrontal Cortex (mPFC), Fiber Photometry (FIP), Barnes Maze (BM), Glutamatergic, Gabaergic, Neuronal Activity, Neuronal Activation Patterns, Neuronal Dynamics.

O córtex pré-frontal medial (mPFC) é essencial na execução de tarefas cognitivas, no entanto, pouco se sabe sobre como esses neurônios são modulados durante tarefas específicas e qual subtipo de neurônios é responsável por isso. Portanto, com a intenção de abordar essa questão, registramos os padrões de ativação de neurônios gabaérgicos e glutamatérgicos do mPFC por meio de fotometria de fibra (FIP) em camundongos, enquanto realizávamos simultaneamente a tarefa cognitiva do Labirinto de Barnes (BM) (ensaio comportamental de 4 dias). Além disso, um protocolo estrutural e procedimental alterado para o BM foi validado neste estudo devido a modificações necessárias que permitiram a realização simultânea de FIP e BM. Uma validação bem-sucedida do protocolo foi seguida pelos nossos resultados preliminares, que mostraram que tanto os neurônios glutamatérgicos quanto os gabaérgicos apresentaram mudanças significativas na intensidade de ativação e no número de eventos em contextos específicos ao longo dos dias da tarefa. Além disso, quando estratificados e cruzados com parâmetros de desempenho do BM, como latência para completar as tarefas e estratégia adotada, os neurônios glutamatérgicos e gabaérgicos apresentaram uma diminuição significativa nos padrões de ativação e no número de eventos de ativação ao longo dos dias. Esses dados sugerem não apenas um papel importante dos neurônios glutamatérgicos e gabaérgicos do mPFC na aprendizagem, memória e tomada de decisões, mas também que os padrões de ativação de cada um desses grupos podem servir como marcadores de progressão e/ou disfunção cognitiva. PALAVRAS-CHAVE: Memória, Aprendizagem, Tomada de Decisões, Córtex Pré-Frontal Medial (mPFC), Fotometria de Fibra (FIP), Labirinto de Barnes (BM), Glutamatérgico, Gabaérgico, Atividade Neuronal, Padrões de Ativação Neuronal, Dinâmica Neuronal.

B220 expression as an immunological marker for differentiation of Feline Leukemia Virus carrying cats / A expressão de B220 como um marcador imunológico para diferenciação de gatos portadores do vírus da Leucemia Felina

ABSTRACT: Feline leukemia virus (FeLV) causes an infection in cats that, in some cases, can also be reported with other pathologies, such as infection with feline immunodeficiency virus (FIV), feline infectious peritonitis (FIP), and lymphoma. Although, a compromised immune response is reported in these animals, little is known about the immunological state of their cells. To shed some light in this area, we studied peripheral blood samples from both infected and non-infected cats with FeLV, with or without FIV, FIP, and lymphoma. We tested a panel of monoclonal antibodies (n=11) against mouse and human antigens and we reported that cat leukocytes can be stained with anti-mouse B220 monoclonal antibody; therefore, percentages of B cells were evaluated in different cat groups. Our results showed that cats with FeLV and FIP, or with leukemia, presented a large decrease in B220+ mononuclear cells. However, FeLV+ cats without clinical signs, or with unspecific clinical signs, had the same amount of B220+ mononuclear cells as healthy cats (control cats). Since the expression of B220 is exclusively restricted to the naïve B cell population, we inferred that the absence of these B cells in FeLV+ cats is related to other conditions that affect B cell numbers, such as viral infections and leukemias. Therefore, the amount of naïve B cells in peripheral blood (i.e., B220+ cells) can be used to identify FeLV+ cats concomitantly carrying FIP or leukemia, from FeLV+ cats with lymphoma or without any clinical signs.

RESUMO: O vírus da leucemia felina (FeLV) causa de uma infecção em gatos, que também podem ter outras patologias, como a imunodeficiência felina (FIV), a peritonite infecciosa felina (FIP) e linfoma. Embora uma resposta imune comprometida seja encontrada nestes animais, pouco se sabe sobre o estado imunológico de suas células. Para ampliar o número de testes com a finalidade de avaliar o estado imunológico destes animais, estudamos amostras de sangue periférico de gatos infectados, ou não, com FeLV, e que apresentavam (concomitantemente) FIV, FIP e linfoma. Para isto, amostras de sangue foram marcadas com um painel de anticorpos monoclonais contra antígenos de camundongos e humanos (n = 11), para avaliar seu potencial para estudos imunológicos em gatos. De todo o painel de anticorpos testados, apenas o anticorpo anti-B220 de camundongo foi capaz de marcar leucócitos de gato. Nossos resultados mostraram que os gatos com FeLV e FIP, ou com leucemia, apresentaram uma grande diminuição nas células mononucleares B220+. No entanto, gatos FeLV+ sem sinais clínicos, ou com sinais clínicos inespecíficos, tiveram a mesma quantidade de células B220+ que os gatos saudáveis (gatos controle). Como a expressão de B220 é restrita à população de células B naïve, podemos inferir que a ausência dessas células B em gatos FeLV+ está relacionada a outras condições que afetam o número destas células, como infecções virais e leucemias. Portanto, a quantidade de células B naïve no sangue periférico pode ser usada para identificar gatos FeLV+ concomitantemente portadores de PIF ou leucemia, de gatos FeLV+ com linfoma ou sem sinais clínicos.

Recent advances in the classification and management of hypereosinophilia

Numerous disorders and etiologies may underlie increased eosinophil counts. Hypereosinophilia (HE) is defined as a peripheral blood eosinophil count greater than 1,500/mm3 and may be potentially harmful because of tissue damage. Hypereosinophilic syndrome (HES) also represents a heterogeneous disorder characterized by persistent HE with the evidence of organ dysfunction, clinical symptoms, or both caused by eosinophilia. The refining criteria and subclassification of HE and HES are currently being revised on cellular and molecular based diagnostic methods. Initial approaches focus on evaluating various underlying causes, including helminthic infections, adverse drug reactions, allergic diseases, and neoplastic diseases. When secondary causes of HE are excluded, the workup should proceed to the evaluation of primary/clonal bone marrow disease, including fip 1-like 1-platelet driven growth factor receptor alpha (FIP1L1-PDGFRA) mutation. Concurrently, if the patient has symptoms and signs, organ damage or dysfunction must be evaluated. Although, corticosteroids are the mainstay of therapy in confirmed HES, imatinib is considered a definitive treatment for FIP1L1-PDGFRA, platelet driven growth factor receptor beta rearranged HE and HES. In this article, we discuss recent advances in the classification of and practical approaches to HE and HES. In addition, we introduce several promising therapies for HE and HES.

Hypereosinophilic Syndrome: A rare differential diagnosis for profound leucocytosis

@#A broad range of disorders are present with eosinophilia and these include infectious, allergic, rheumatic, neoplastic, endocrine and idiopathic disorders which range from benign to life-threatening illnesses. All these conditions create a heterogeneous list of clinical presentation that patients may display, thus creating a diagnostic challenge for clinicians. We present a patient with a broad range of clinical features and hematological counts that fit into the diagnosis of Hypereosinophilic Syndrome (HES). He was investigated reasonably to rule the various possible differentials and subsequently started on Prednisone therapy.

FIP1L1/PDGFRα fusion gene-negative chronic eosinophilic leukemia with t(5; 12)(q31;p13): a case report and review of literatures / 中华内科杂志

Objective To deepen the understanding of chronic eosinophilic leukemia (CEL).Methods The course of diagnosis and treatment in a case of FIP1L1/PDGFRα fusion gene negative CEL was reported. Flow cytometry was used to analyze the immunophenotype of the cells in peripheral blood and pleural fluid. Karyotype was analyzed with G-banding. The expression of FIP1L1/PDGFRα fusion gene was detected by RT-PCR technique. Routine pathological examination of the tissues from bone marrow, lung and spleen were performed. Result A sixteen-year-old girl had severe anemia, fever, splenomegaly,thrombocytopenia and dominant hypereosinophilia lasting for 22 months. Trephine biopsy showed a hypercellular marrow with eosinophilic proliferation and moderate reticular fibrosis. Eosinophilic infiltration was found in lung and spleen and embolism was also found in spleen. She had a clonal chromosomal abnormality t(5;12)(q31;p13). The expression of FIP1L1/PDGFRα was negative. An abnormal clone of T cells expressing CD3-,CD4-,CD8- was found in peripheral blood and pleural fluid, in which the cional T cell accounted for 5.43% and 1.66% of the total lymphocytes respectively. The patient was refractory to treatment with hydroxyurea, prednisone and interferon alpha. She had poor response to a combination of therapy with low dose cytosine arabinoside, mitoxantrone, vincristine, cyclophosphamide, methotrexate and prednisone. She did not respond to imatinib and died of multiple organ failure. Conclusion The present case fulfilled the WHO diagnostic criteria of FIP1L1/PDGFRα(-) CEL which did not respond to routine treatment and imatinib. Allogenic stem cell transplantation should be considered as early as possible in this case. It is noteworthy that clonal CD3-,CD4-,CD8- T-cell abnormality is related to the pathogenesis of CEL.