[Moyamoya disease: revision and description of a number of pedriatic cases]. / Enfermedad de moyamoya: descripción de una serie de casos pediátricos.

INTRODUCTION: Moyamoya disease is caused because of progressive occlusion of the arterial circle of Willis, leading to a compensatory net-like abnormal vessels development. The objective is to describe the number of cases in our center (tertiary hospital). PATIENTS AND METHODS: Retrospective study. Revision of pediatric medical histories diagnosed of moyamoya disease or moyamoya syndrome (in case of predisposing disease) between 2005 and 2018. Demographic variables were collected, related to diagnosis, risk factors, treatment, and follow-up. RESULTS: Seven cases were collected with a median age of 6 years and an equitable distribution by sex. Five associated predisposing pathologies (Down syndrome, neurofibromatosis, sickle cell disease, Behcet). The main clinical diagnosis was neurological focus (five cases), followed by epileptic seizures (four), and headache (two). One was asymptomatic at diagnosis. Six strokes were documented, five of them were isquemic. The arteriography (goldstardard) was made in five patients. Five presented bilateral involvement of the vessels, the internal carotid arteries and the middle cerebral arteries were the most affected. Six received acetylsalicylic acid treatment and five of them required antiepileptic drugs. Revascularization surgery (encephaloduroarteriomyosinangiosis) was performed in four patients, and in one, strokes persisted. The most prevalent sequelae were hemiparesis and psychomotor retardation. CONCLUSIONS: The risk factors presented in our patients match to those described in the literature. The symptoms at the onset can be diverse and ischemic strokes predominate in our series. Revascularization surgery was effective in more than half of the cases. Subsequent follow-up is necessary to assess complications and sequelae.

TITLE: Enfermedad de moyamoya: descripción de una serie de casos pediátricos.Introducción. La enfermedad de moyamoya se produce por la oclusión de las arterias alrededor del polígono de Willis y genera una amplia red de vasos colaterales. El objetivo es describir la serie histórica de nuestro centro (hospital terciario). Pacientes y métodos. Es un estudio retrospectivo. Se hizo una revisión de historias clínicas de pacientes pediátricos diagnosticados de enfermedad o síndrome de moyamoya (si patología predisponente) entre 2005 y 2018. Se recogieron variables demográficas, relacionadas con el diagnóstico, factores de riesgo, tratamiento y seguimiento. Resultados. Se obtuvieron siete casos, con una mediana de edad de seis años y distribución por sexos equitativa. Cinco asociaban patologías predisponentes (síndrome de Down, neurofibromatosis, drepanocitosis y Behçet). La clínica predominante en el diagnóstico fue focalidad neurológica (cinco casos), seguida de crisis epilépticas (cuatro) y cefalea (dos). Un paciente era asintomático en el momento del diagnóstico. Se documentaron seis ictus, cinco de los cuales fueron isquémicos. La arteriografía (técnica de referencia) constaba en cinco pacientes. Cinco presentaban afectación bilateral y estaban mayormente afectadas las arterias carótidas internas y las cerebrales medias. Seis recibieron tratamiento con ácido acetilsalicílico y cinco necesitaron fármacos antiepilépticos. La cirugía de revascularización (encefaloduroarteriomiosinangiosis) se realizó en cuatro pacientes y en uno persistieron los ictus. Las secuelas más prevalentes fueron hemiparesia y retraso psicomotor. Conclusiones. Los factores de riesgo presentados en nuestros pacientes se ajustan a los descritos en la bibliografía. La clínica en el inicio puede ser diversa y predominan los ictus isquémicos en nuestra serie. La cirugía de revascularización fue efectiva en más de la mitad de los casos. Es necesario un seguimiento posterior para evaluar complicaciones y secuelas.

Enfermedad de moyamoya: descripción de una serie de casos pediátricos / Moyamoya disease: revision and description of a number of pedriatic cases

Introducción: La enfermedad de moyamoya se produce por la oclusión de las arterias alrededor del polígono de Willis y genera una amplia red de vasos colaterales. El objetivo es describir la serie histórica de nuestro centro (hospital terciario). Pacientes y métodos: Es un estudio retrospectivo. Se hizo una revisión de historias clínicas de pacientes pediátricos diagnosticados de enfermedad o síndrome de moyamoya (si patología predisponente) entre 2005 y 2018. Se recogieron variables demográficas, relacionadas con el diagnóstico, factores de riesgo, tratamiento y seguimiento. Resultados: Se obtuvieron siete casos, con una mediana de edad de seis años y distribución por sexos equitativa. Cinco asociaban patologías predisponentes (síndrome de Down, neurofibromatosis, drepanocitosis y Behçet). La clínica predominante en el diagnóstico fue focalidad neurológica (cinco casos), seguida de crisis epilépticas (cuatro) y cefalea (dos). Un paciente era asintomático en el momento del diagnóstico. Se documentaron seis ictus, cinco de los cuales fueron isquémicos. La arteriografía (técnica de referencia) constaba en cinco pacientes. Cinco presentaban afectación bilateral y estaban mayormente afectadas las arterias carótidas internas y las cerebrales medias. Seis recibieron tratamiento con ácido acetilsalicílico y cinco necesitaron fármacos antiepilépticos. La cirugía de revascularización (encefaloduroarteriomiosinangiosis) se realizó en cuatro pacientes y en uno persistieron los ictus. Las secuelas más prevalentes fueron hemiparesia y retraso psicomotor. Conclusiones: Los factores de riesgo presentados en nuestros pacientes se ajustan a los descritos en la bibliografía. La clínica en el inicio puede ser diversa y predominan los ictus isquémicos en nuestra serie. La cirugía de revascularización fue efectiva en más de la mitad de los casos. Es necesario un seguimiento posterior para evaluar complicaciones y secuelas.(AU)

Introduction: Moyamoya disease is caused because of progressive occlusion of the arterial circle of Willis, leading to a compensatory net-like abnormal vessels development. The objective is to describe the number of cases in our center (tertiary hospital). Patients and methods: Retrospective study. Revision of pediatric medical histories diagnosed of moyamoya disease or moyamoya syndrome (in case of predisposing disease) between 2005 and 2018. Demographic variables were collected, related to diagnosis, risk factors, treatment, and follow-up. Results: Seven cases were collected with a median age of 6 years and an equitable distribution by sex. Five associated predisposing pathologies (Down syndrome, neurofibromatosis, sickle cell disease, Behçet). The main clinical diagnosis was neurological focus (five cases), followed by epileptic seizures (four), and headache (two). One was asymptomatic at diagnosis. Six strokes were documented, five of them were isquemic. The arteriography (goldstardard) was made in five patients. Five presented bilateral involvement of the vessels, the internal carotid arteries and the middle cerebral arteries were the most affected. Six received acetylsalicylic acid treatment and five of them required antiepileptic drugs. Revascularization surgery (encephaloduroarteriomyosinangiosis) was performed in four patients, and in one, strokes persisted. The most prevalent sequelae were hemiparesis and psychomotor retardation. Conclusions: The risk factors presented in our patients match to those described in the literature. The symptoms at the onset can be diverse and ischemic strokes predominate in our series. Revascularization surgery was effective in more than half of the cases. Subsequent follow-up is necessary to assess complications and sequelae.(AU)

Role of FK778 alone or in combination with tacrolimus or mTOR inhibitors as an immunomodulator of immunofunctions: in vitro evaluation of T cell proliferation and the expression of lymphocyte surface antigens.

We evaluated the in vitro capacity of FK778, alone or in combination with other immunosuppressive drugs: Tacrolimus (TRL); Sirolimus (SRL), Everolimus (EVL), to inhibit clonal expansion of T-lymphocytes and expression of lymphocyte-activation surface antigens; secondly, we compared the immunosuppressive potential of FK778 combined with TRL, SRL and EVL with the same combinations using Mycophenolic acid (MPA) as antimetabolite. Lymphocyte proliferation was assessed by 3H-Thymidine incorporation, in whole blood cultures stimulated with ConA. The effect of FK778 on alloresponse was evaluated by MLC and the expression of lymphocyte surface antigens by cytometry. FK778, TRL, SRL and EVL showed a high in vitro capacity to inhibit lymphocyte proliferation in a concentration-dependent way. Combinations of FK778 with TRL, SRL, or EVL presented an additive effect, especially FK778+TRL. Similar inhibition capacity of the clonal expansion was observed, when FK778 was combined with TRL, SRL or EVL, respecting the same combinations but using MPA instead of FK778. In addition, FK778 inhibited the expression of lymphocyte surface antigens involved in activation, co-stimulatory and apoptosis signals. In conclusion, FK778 inhibits the proliferative response induced by mitogeneic and allogeneic stimuli and the expression of surface antigens. Combinations of FK778 with TRL or mTOR inhibitors presented an additive effect and their action on T cell proliferation was similar to that of combinations with MPA. Since FK778, TRL and mTOR inhibitors present different action mechanisms and involve different cellular targets, these combinations may help prevent episodes of allorejection in organ transplants. FK778 and mTOR inhibitors may represent an alternative treatment for patients with renal failure.

Immunological benefits of antiretroviral therapy in very early stages of asymptomatic chronic HIV-1 infection.

OBJECTIVES: To assess whether an almost complete restoration of immune system can be achieved when antiretroviral therapy is initiated at very early stages of asymptomatic chronic HIV-1 infection. DESIGN: T cell subsets and cell-mediated responses were analysed at baseline and after 12 months of either a double or a triple antiretroviral therapy in 26 asymptomatic HIV-1-infected patients with CD4 T cell counts > 500 x 10(6) cells/l and a baseline plasma viral load > 10000 copies/ml. RESULTS: Triple therapy was significantly more effective in reducing plasma HIV RNA to undetectable levels, in returning CD4:CD8 ratio to nearly normal levels, in reducing activated cells (CD38) and in increasing naive (CD45RA+CD45RO-) and memory (CD45RA-CD45RO+) CD4 cells. Both double and triple therapies caused a clear decrease in memory (CD45RA-CD45RO+) CD8 cells as well as a significant increase in the CD28 subset of CD8 cells. At baseline, there was an important increase in cells producing interferon-gamma (IFNgamma) with no significant abnormalities in T lymphocytes producing interleukin 2 (IL-2), tumour necrosis factor alpha and interleukin 4. Both types of therapy reduced IFNgamma- and IL2-producing CD4 T lymphocytes while IFNgamma-producing CD8 cells remained increased. Even before therapy, these HIV-1-positive patients lacked significant abnormalities in the T cell responsiveness to polyclonal stimuli as well as in the secretion of CCR5 chemokines by peripheral blood mononuclear cells. CONCLUSIONS: Initiating highly active antiretroviral therapy at very early stages of chronic HIV-1 infection allows rapid and almost complete normalization of T cell subsets and preservation of T cell functions. These early-treated patients could be excellent candidates for receiving additional HIV-specific immune-based therapies, which might be essential for the control of HIV infection.

Isolation of two CD50 (ICAM-3)-negative Jurkat T-cell clones and their application for analysis of CD50 function.

The leukocyte differentiation antigen CD50 (intercellular adhesion molecule-3, ICAM-3), mediates cell-cell adhesion through its ligand LFA-1 and is a transducting receptor molecule during T-cell activation. Since CD50 homologues in other species have not yet been identified, the role of this molecule can only be analyzed in human cell models. Thus, to better study CD50 function in T cells, we have obtained two CD50-negative T-cell clones, named CAMY.1 and CAMY.2. These clones were derived from the Jurkat T-cell variant PPL.1. Data from analysis of protein expression, specific mRNA content and calcium mobilization assays have confirmed the absence of functional CD50 molecules on these two clones. Thus, CAMY.1 and CAMY.2 show no CD50 expression by phenotypical and immunoprecipitation analysis. CD50-specific mRNA content is undetectable by Northern blot analysis in these clones and, only, when RT-PCR was performed could specific mRNA be detected. Additionally, CD50 cross-linking on theses clones shows no increase in intracellular calcium. Transfection of CD50 cDNA on CAMY cells restores not only CD50 surface expression, but its functional ability to induce calcium mobilization, CD69 upregulation and cell morphological changes. The CAMY.1 and CAMY.2 clones provide useful model systems to analyze CD50 function in T cells.

CD50 (intercellular adhesion molecule 3) stimulation induces calcium mobilization and tyrosine phosphorylation through p59fyn and p56lck in Jurkat T cell line.

The leukocyte differentiation antigen, CD50, has been recently identified as the intercellular adhesion molecule 3 (ICAM-3), the third counter-receptor of leukocyte function-associated antigen 1 (LFA-1). This molecule seems to be specially involved in the adhesion events of the initial phases of the immune response. To characterize the role of CD50 in leukocyte interactions, the different molecular events induced after cross-linking of CD50 on T cell-derived Jurkat cell line have been analyzed. When cells were incubated with anti-CD50 mAbs and cross-linked with polyclonal goat anti-mouse immunoglobulins, a rise in intracellular calcium concentration ([Ca2+]i) was observed. This increase in [Ca2+]i was mainly due to the uptake of extracellular Ca2+. This Ca2+ flux involved tyrosine phosphorylations and was further increased by CD3 costimulation. These data, together with those obtained by phosphotyrosine (P-Tyr) immunoprecipitation and in vitro kinase assays, suggested the involvement of protein-tyrosine kinases (PTK) in CD50 transduction pathways. By using specific antisera, the presence of p56lck and p59fyn protein tyrosine kinases (PTK) was clearly demonstrated in the CD50 immunoprecipitates. These findings suggest that the interaction of CD50 with its natural ligand (LFA-1) may result in T lymphocyte activation events, in which CD50 could play a very active role after antigen triggering.

Impaired post-transcriptional expression of interleukin-2 receptor in pokeweed mitogen-activated T cells.

The expression and role of interleukin-2/interleukin-2 receptor (IL-2/IL-2R) system in the pokeweed mitogen (PWM)-induced T cell mitogenesis was studied. In the absence of monocytes (Mo), both soluble and Sepharose-bound PWM fail to induce T cell mitogenesis even when exogenous IL-2 or IL-1 or IL-1 + IL-2 or IL-4 are also present. In the presence of Mo, PWM stimulation of T lymphocytes (highly depleted of B lymphocytes) induces as much IL-2 mRNA as phytohemagglutinin (PHA), but results in higher and persistent IL-2 levels in culture supernatants despite the concomitant T cell mitogenesis, suggesting that PWM-activated T cells do not utilize the IL-2 they produce. Confirming this notion, Mo-dependent PWM-preactivated T cells, as compared to PHA-preactivated ones: (a) failed to consume exogenous IL-2 and their mitogenic response did not increase upon exposure to exogenous IL-2; (b) exhibited very low numbers of high-affinity IL-2R; and (c) showed lower expression of IL-2R p55 and undetectable expression of IL-2R p75 on their surface. Moreover, the PWM-induced T cell mitogenesis was not inhibited by anti-IL-2 or CD25 antibodies and only partially (50%-60%) inhibited by cyclosporin A, while these treatments abrogated the PHA-induced one. PWM-activated T cells, as compared to the PHA-activated ones, exhibited as high (p55) or even higher (p75) mRNA expression of both IL-2R p55 and p75 subunits. The possibility that PWM interferes with IL-2R subunits once expressed on the T cell surface was excluded. Thus, intracellular PWM-related events are likely to impair IL-2R expression post-transcriptionally. Possible explanations for this effect and its relation with the capacity of PWM to induce T cell-dependent B cell differentiation are discussed.