Modulation of glutathione intracellular levels alters the spontaneous proliferation of lymphocyte from HTLV-1 infected patients.

The human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus associated with neoplasias and inflammatory diseases, such as adult T-cell leukemia/lymphoma and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1-infected individuals present a spontaneous T lymphocyte proliferation. This phenomenon is related to the HTLV-1-proviral load and the persistence of the infection. Viral proteins induce many cellular mediators, which can be associated with the abnormal cellular proliferation. The intracellular levels of glutathione (GSH) are important to modulate the cellular proliferation. The aim of this study was to investigate the correlation between the modulation of intracellular GSH levels and the spontaneous lymphocyte proliferation during the HTLV-1 infection. Intracellular GSH level can be modulated by using dl-buthionine-[S,R]-sulfoximine (BSO, GSH synthesis inhibitor) and N-acetylcysteine (NAC, peptide precursor). Our results demonstrated that BSO was capable of inducing a decrease in the spontaneous proliferation of PBMC derived from HTLV-1 carriers. On the other hand, the GSH precursor induces an increase in mitogen-stimulated cellular proliferation in infected and uninfected individuals. Similar results were observed by the inhibition of ABCC1/MRP1 protein, augmenting the mitogen-induced proliferation. This effect can be related with an increase in the GSH levels since ABCC1/MRP1 transports GSH to the extracellular medium. There was a significant difference on the expression of CD69 and CD25 molecules during the lymphocyte activation. We did not observe any alterations on CD25 expression induced by BSO or NAC. However, our results demonstrated that NAC treatment induced an increase in CD69 expression on unstimulated CD8(+) T lymphocytes obtained from HTLV-1 infected individuals, healthy donors and HTLV carriers. Therefore, our results suggest that the cellular proliferation promoted by the infection with HTLV-1 and the activation phenotype of CD8(+) T lymphocytes can be regulated by changing the intracellular GSH levels; suggesting the modulation of these intracellular levels as a new approach for the treatment of pathologies associated with the HTLV-1 infection.

Sickle cell disease: acute clinical manifestations in early childhood and molecular characteristics in a group of children in Rio de Janeiro.

OBJECTIVES: To describe clinical events of sickle cell disease and the correlation with ß-globin haplotypes and α-thalassemia in under 6-year-old children. METHODS: A retrospective study was conducted of under 6-year-old children from the neonatal screening program in Rio de Janeiro. Forty-eight male and 48 female children were enrolled in this study, 79 with sickle cell anemia and 17 with hemoglobin SC. The mean age was 29.9 (standard deviation = 20.9) months, 62 (16.2 ± 8.6) were aged between 0-3 years old and 34 (54.9 ± 11.3) were from 3-6 years old. Painful events, acute splenic sequestration, hemolytic crises, hand-foot and acute chest syndromes and infections were evaluated. RESULTS: The events were more frequent in under 3-year-old children, 94% of children had at least one episode. Infection was the most common event affecting 88.5% of children. Acute splenic sequestration took place earlier, while painful crises and acute chest syndromes in under 6-year-old children. Thal-α 3.7 was observed in 20.9% of cases. Bantu was the most frequent haplotype found, followed by Benin. No correlation was observed between clinical events and ß-globin haplotypes. Children with sickle cell anemia and α-thalassemia have less infectious events. No correlation was found among these polymorphisms and clinical events, however, the majority of children with Bantu/Bantu and without α-thalassemia had more clinical events.

Health care-associated infection and hospital readmission in a home care service for children.

The number of children in home health care services is increasing, and there is a need for infection control regulation in this environment. We describe the main causes of infection and hospitalization in children assisted by a pediatric home health care service in Rio de Janeiro, Brazil.

Adult T-cell leukemia/lymphoma: a case report of primary cutaneous tumoral type.

BACKGROUND: Adult T-cell leukemia/lymphoma (ATLL) is a distinctive peripheral T- lymphocytic malignancy associated with human T-cell lymphotropic virus type 1 (HTLV-1). It may closely resemble other skin lymphomas, particularly mycosis fungoides (MF). CASE REPORT: A 38-year-old woman presented some ellipsoid scaling patches lasting 18 months and developed a large tumoral lesion in the abdomen, which were previously diagnosed as MF. Although histopathologic and immunohistochemistry findings were in consonance with this diagnosis, the fast progression of the disease raised the suspicion that it could represent another type of T-cell lymphoma. The work-up revealed a positive anti-HTLV-1 serology and molecular studies confirmed the monoclonal integration of HTLV-1 provirus into neoplastic cells of the skin, but not into circulating lymphocytes. Extensive investigations were unable to demonstrate any systemic involvement. The final diagnosis was of primary cutaneous type of ATLL. The patient was submitted to a chemotherapy regimen with cyclophosphamide, doxorubicin, vincristine and prednisone, later to conjugated dexamethasone and surgical cytoreduction and then to a second line treatment with gemcitabine, resulting in partial response. A bone marrow heterologous transplantation was performed, but failed to achieve a sustained remission. DISCUSSION: ATLL is a rare lymphoid malignancy in non-endemic HTLV-1 areas, the diagnosis of which could be missed if not highly suspected. In addition to the four subtypes of Shimoyama classification (acute, lymphomatous, chronic and smoldering), a fifth one denominated primary cutaneous and characterized by presence of lesions only in the skin had been proposed and is herein exemplified.

Monocytes from HTLV-1-infected patients are unable to fully mature into dendritic cells.

Human T-cell lymphotropic virus type 1 (HTLV-1) is a causative agent of adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. HTLV-1-associated myelopathy/tropical spastic paraparesis is a chronic inflammatory disease characterized by loss of motor movement in response to spinal marrow cell destruction by T lymphocytes. To perform their cellular function, T cells need to be activated by antigen-presenting cells, such as dendritic cells (DCs). The aim of this work was to analyze DC differentiation and activation from monocytes of HTLV-1-infected individuals. We demonstrated that monocytes from HTLV-1-infected patients who had been stimulated to differentiate had an impaired loss of CD14 expression, expressed low levels of CD1a, and maintained secretion of tumor necrosis factor-α compared with monocytes from noninfected donors. We further evaluated DC activation by tumor necrosis factor-α. We observed that in response to activation, DCs that were derived from noninfected donors had an increase in the percentage of CD83(+), CD86(+), and human leukocyte antigen-DR(+) cells, whereas in DCs derived from HTLV-1-infected patients, the percentage of CD83(+), CD86(+), and human leukocyte antigen-DR(+) cells remained similar to that of nonactivated cells. Moreover, these cells had an impaired capacity to stimulate allogeneic T lymphocytes. We demonstrated that DC maturation was altered in HTLV-1-infected patients, which could contribute to the development of HTLV-1-associated diseases.