Imunoterapia com células natural killer : um caminho possível para o tratamento da Leucemia Mielóide Aguda também no Brasil

The allogeneic hematopoietic stem cell transplantation (HSCT) can cure intermediate and high-risk acute myeloid leukemia. Even with the development of strategies to reduce HSCT toxicity, this is still a complex treatment with high morbidity and mortality. Knowledge of the graft versus leukemia effect of HSCT has prepared the way for the development of Adoptive Immunotherapy or in vitro expansion of activated lymphocytes without alloreactivity, with subsequent intravenous infusion. The infusion of genetically modified T lymphocytes and haploidentical natural killer cells has been tested as an alternative to HSCT with very interesting results worldwide and in Brazil, as we not only have the technology of in vitro expansion of clinical grade lymphocytes available, but also do it according to the Good Manufacturing Practices that have been determined internationally.O transplante de células-tronco hematopoéticas (TCTH) alogênico é curativo para leucemia mielóide aguda de risco intermediário e alto. Mesmo com o desenvolvimento de estratégias para minorar a toxicidade do TCTH, este ainda é um tratamento complexo com elevada morbi-mortalidade. O conhecimento sobre o efeito enxerto contra leukemia do TCTH pavimentou o caminho para o desenvolvimento da Imunoterapia Adotiva ou expansão in vitro de linfócitos ativados, sem alo- reatividade, com posterior infusão endovenosa. A infusão de Linfócitos T geneticamente modificados e de células Natural Killer haploidenticas tem sido testada como alternativa ao TCTH com resultados bastante interessantes no mundo e no Brazil já que não apenas dominamos a tecnologia de expansão in vitro de linfócitos em grau clínico, como o fazemos segundo as Boas Práticas de Manufatura determinadas internacionalmente

Peripheral blood persistence and expansion of transferred non-genetically modified Natural Killer cells might not be necessary for clinical activity

Natural killer (NK) cells are innate lymphocytes that react without previous exposition to virus infected or malignant cells and stimulate adaptive immune response to build a long-lasting immunity against it. To that end, tissue resident NK cells are predominantly regulatory as opposed to cytotoxic. In the hematopoietic stem cell transplant (HSCT) setting, which curative potential relies on the graft versus leukemia effect, NK cells are known to play a significant role. This knowledge has paved the way to the active investigation on its anti-tumor effect outside the stem cell transplant scenario. Based on the relevant literature on the adoptive transfer of non-genetically modified NK cells for the treatment of relapsed/refractory acute leukemia and on our own experience, we discuss the role of donor cell peripheral blood persistence and expansion and its lack of correlation with anti-leukemia activity

Aspectos Ambientais e Genéticos no Desenvolvimento de Leucemias

The causes of AL are likely to involve an interaction between genetic susceptibility and environment. Polymorphisms in genes coding metabolizing/detoxification enzymes are responsible for this susceptibility. Environmental exposure (occupational or recreational) may also be involved with the etiology of leukemia. Some studies have described that infant leukemia may have the initiation period during in utero development and this may be caused by the parental pre or during the pregnancy period. The aim of this study was to analyze polymorphisms of GSTM1 and GSTT1 genes in order to verify if they have a role in genetic susceptibility to AL and correlate with some environmental aspects. Genomic DNA from 87 patients was analyzed by a multiplex PCR methodology. Material from twenty four families (the patient, the mother and/or the father) were also analyzed and a questionnaire about environmental aspects was applied. Significant increase in the prevalence of GSTT1 null genotype was detected in the patient group comparing to controls (40% X 23%) (P=0.005). No difference was found in the prevalence of GSTM1 null genotype between AL patients and controls (50% X 50%). We detected higher prevalence of occupational exposure to solvents among the fathers, being this an important aspect on leukemia development.A etiologia das LA pode ser explicada pela combinação de fatores genéticos e ambientais. Como exemplo das influências genéticas podem-se citar polimorfismos de genes de metabolização/detoxificação e, como agente ambiental à exposição ocupacional e por lazer. Tem sido descrito que Leucemias infantis poderiam ter a iniciação ocorrendo in útero, devido à exposição parental pré-ou durante a gestação. Este trabalho tem por objetivo analisar os polimorfismos dos genes GSTM1 e GSTT1 em relação à suscetibilidade de desenvolvimento de LA e a relação com alguns fatores ambientais. O DNA genômico de um banco de 87 pacientes foi analisado pela técnica de PCR multiplex. Também foram coletados dados de 24 famílias (pacientes pai e/ou mãe) e aplicado questionário sobre exposição. Foi detectado aumento significativo da freqüência do genótipo GSTT1 nulo quando comparado com uma população controle (40% X 23%) (P=0.005). A freqüência do genótipo nulo para GSTM1 nos pacientes não apresentou diferença significativa com relação aos controles (50% X 50%). Foi detectada uma prevalência alta de pais que relatam exposição a tintas e solventes no período de pré-concepção, podendo este ser um fator importante na origem da doença

Bone marrow mesenchymal stem cells in acute-on-chronic liver failure grades 2 and 3 : a phase I-II randomized clinical trial

Introduction: Acute-on-chronic liver failure (ACLF) is an acute liver decompensation in cirrhotic patients, which leads to organ failures and high short-term mortality. The treatment is based on the management of complications and, in severe cases, liver transplantation. Since specific treatment is unavailable, we aimed to evaluate the safety and initial efficacy of bone marrow mesenchymal stem cells (BM-MSC) in patients with ACLF Grades 2 and 3, a population excluded from previous clinical trials. Methods: This is a randomized placebo-controlled phase I-II single center study, which enrolled 9 cirrhotic patients from 2018 to 2020, regardless of the etiology. The control group (n=5) was treated with standard medical therapy (SMT) and placebo infusion of saline. The intervention group (n=4) received SMT plus 5 infusions of 1 × 10^6 cells/kg of BM-MSC for 3 weeks. Both groups were monitored for 90 days. A Chi-square test was used for qualitative variables, and the t-test and Mann–Whitney U test for quantitative variables. The Kaplan–Meier estimator was used to build survival curves. In this study, we followed the intention-totreat analysis, with a significance of 5%. Results: Nine patients with a mean Child–Pugh (CP) of 12.3, MELD of 38.4, and CLIF-C score of 50.7 were recruited. Hepatitis C and alcohol were the main etiologies. )e average infusion per patient was 2.9 and only 3 patients (2 in control and 1 in the BM-MSC group) received all the protocol infusions. There were no infusion-related side effects, although one patient in the intervention group presented hypernatremia and a gastric ulcer, after the third and fifth infusions, respectively. )e survival rate after 90 days was 20% (1/5) for placebo versus 25% (1/4) for the BM-MSC. The patient who completed the entire MSC protocol showed a significant improvement in CP (C-14 to B-9), MELD (32 to 22), and ACLF (grade 3 to 0). Conclusion: BM-MSC infusion is safe and feasible in patients with ACLF Grades 2 and 3

Survival of patients submitted to allogeneic bone marrow transplantation

Introdução: O transplante de células-tronco hematopoiéticas (TCTH) alogênico é um procedimento que oferece um potencial de cura para doenças hematológicas malignas e benignas. O benefício da técnica está especialmente relacionado ao aumento da sobrevida em pacientes com doadores HLA-compatíveis em cujos casos o tratamento quimioterápico mostrouse insuficiente ou ineficaz. Objetivos: Analisar a sobrevida de pacientes que receberam TCTH alogênico aparentado no Serviço de Hematologia Clínica e Transplante de Medula Óssea (SHCTMO) do Hospital de Clínicas de Porto Alegre (HCPA). Métodos: Estudo de coorte prospectiva com análise de sobrevida de pacientes transplantados entre 1994 e 2003. Resultados: Foram analisados 133 pacientes com idade média de 30,8±14,8 anos com um tempo médio de 26,8 meses entre o diagnóstico e o TCTH. Cinco anos após o transplante, 71 pacientes (53,4%) estavam vivos, 22 pacientes tinham leucemia mieloide aguda (LMA), 54, leucemia mieloide crônica (LMC), e seis padeciam de síndrome mielodisplásica (SMD), sendo que, em 5 anos, a sobrevida foi de 52, 50 e 33%, respectivamente. Dos 26 pacientes transplantados por anemia aplásica (AA), 66,7% tinham idade inferior a 20 anos, e 61,5% dos que tinham mais de 20 anos estavam vivos. Conclusão: Embora, no nosso estudo, o tempo médio entre o diagnóstico e o transplante tenha sido superior a 2 anos, e embora nossa análise tenha sido apenas estratificada pelo tipo da doença, independentemente do regime de condicionamento ou da fase da doença no momento do TCTH, nossos resultados são superponíveis aos descritos na literatura mundial.Background: Hematopoietic stem cell transplantation (HSCT) represents a curative alternative for malignant and benign hematological diseases. The benefits of the technique are especially related to an increase in the survival of patients with HLA-compatible hematopoietic stem cell donors when chemotherapy or clinical therapy has resulted ineffective. Objectives: To analyze the survival of patients submitted to allogeneic HSCT at the Hematology and Bone Marrow Transplant Service of Hospital de Clínicas de Porto Alegre. Methods: A prospective cohort of all patients submitted to transplantation between 1994 and 2003 was analyzed for overall survival. Results: A total of 133 patients were submitted to transplantation in the study period, with a mean age of 30.8±14.8 years; mean time elapsed between diagnosis and transplant was 26.8 months. Five years after the procedure, 71 patients (53.4%) were alive, 22 patients had acute and 54 had chronic myeloid leukemia, and six patients presented myelodysplastic syndrome; the 5 year overall survival was 52, 50, and 33%, respectively. Of the 26 patients transplanted for aplastic anemia, 66.7% had 20 or less years of age, and 61.5% of the patients older than 20 years were alive. Conclusion: Although the mean time elapsed between diagnosis and transplantation was over 2 years and although our results were stratified by type of disease only, the findings herein reported are similar to those found in the literature, independently of conditioning regimen or disease stage at the time of transplant

Prophylaxis in hemophilia

Hemophilia is an inherited X-linked coagulopathy defined by a deficiency or abnormality in the clotting function of factor VIII (Hemophilia A) or factor IX (Hemophilia B). Prophylaxis – the regular administration of therapeutic products to maintain hemostasis and prevent bleeding – is the mainstream of treatment. Addressing the development and scientific evidence for administrating prophylaxis is the goal of this review. Prophylaxis is the therapeutic modality of choice for people with severe hemophilia, being considered, in principle, a lifelong treatment. It should have an early onset, ideally as a primary, or at least secondary. Even lifelong tertiary prophylaxis seems to offer benefit, although further studies are still lacking. Individualized strategies should lead to an optimization of the dilemma between better joint outcomes versus involved costs