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Blood Adv ; 3(22): 3674-3687, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31765481


An understanding of natural killer (NK) cell physiology in acute myeloid leukemia (AML) has led to the use of NK cell transfer in patients, demonstrating promising clinical results. However, AML is still characterized by a high relapse rate and poor overall survival. In addition to conventional NKs that can be considered the innate counterparts of CD8 T cells, another family of innate lymphocytes has been recently described with phenotypes and functions mirroring those of helper CD4 T cells. Here, in blood and tissues, we identified a CD56+ innate cell population harboring mixed transcriptional and phenotypic attributes of conventional helper innate lymphoid cells (ILCs) and lytic NK cells. These CD56+ ILC1-like cells possess strong cytotoxic capacities that are impaired in AML patients at diagnosis but are restored upon remission. Their cytotoxicity is KIR independent and relies on the expression of TRAIL, NKp30, NKp80, and NKG2A. However, the presence of leukemic blasts, HLA-E-positive cells, and/or transforming growth factor-ß1 (TGF-ß1) strongly affect their cytotoxic potential, at least partially by reducing the expression of cytotoxic-related molecules. Notably, CD56+ ILC1-like cells are also present in the NK cell preparations used in NK transfer-based clinical trials. Overall, we identified an NK cell-related CD56+ ILC population involved in tumor immunosurveillance in humans, and we propose that restoring their functions with anti-NKG2A antibodies and/or small molecules inhibiting TGF-ß1 might represent a novel strategy for improving current immunotherapies.

Mol Cell Pediatr ; 5(1): 1, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29352427


BACKGROUND: Children with inflammatory bowel disease (IBD) or autoimmune hepatitis (AIH) are at risk for severe infections. This is partially a result of their chronic disease condition but, moreover, a side effect of their immunosuppressive therapy. Currently, vaccinations with live vaccines are regarded as contraindicated under immunosuppressive therapy, mainly because of concerns about side effects and a lack of data showing an adequate immune reaction. As there is no systematic study on the individual immunoreactivity under immunosuppressive therapy in this patient group, we analyzed the lymphocyte subgroups and immunoreactivity of lymphocytes in children with IBD or AIH with and without immunosuppressive therapy in vitro. METHODS: We collected whole blood samples from 17 children with IBD or AIH on high-level immunosuppression (IS) (group 1) and 8 on low-level IS (group 2) in comparison with 6 patients without systemic IS (group 3). After Ficoll separation of peripheral mononuclear cells, the samples were analyzed by flow cytometry to determine the lymphocyte subgroups. Furthermore, we stimulated the isolated lymphocytes with phytohemagglutinin (PHA), tetanus antigen, and adenovirus antigen and measured their proliferation by incorporation of H3-thymidine detected in a beta counter. The statistical evaluation was performed by Kruskal-Wallis test and Mann-Whitney U test using a bilateral level of significance of α = 5%. RESULTS: Patients with low- or high-level IS showed no significant difference in the number of lymphocytes or T cells. Interestingly, IS did not influence the lymphocyte proliferation assay significantly regarding median reaction to PHA, tetanus antigen, or adenovirus antigen between the three groups. However, comparing all immunosuppressed patients to the patients without IS, there was a significant difference towards stimulation with tetanus antigen. CONCLUSIONS: Contrary to expectations of a strong influence of IS therapy on the immunoreactivity, this study showed only minor differences between the groups with high-level, low-level, and no IS. Particularly, the in vitro reactivity to adenovirus antigen was nearly the same in all three groups. We assume that-provided a normal distribution and count of lymphocyte subgroups-patients with moderate immunosuppression might be capable of raising an effective immune response to inactivated and live vaccines.

Blood ; 129(21): 2928-2938, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28331055


Reticular dysgenesis (RD) is a rare congenital disorder defined clinically by the combination of severe combined immunodeficiency (SCID), agranulocytosis, and sensorineural deafness. Mutations in the gene encoding adenylate kinase 2 were identified to cause the disorder. Hematopoietic stem cell transplantation (HSCT) is the only option to cure this otherwise fatal disease. Retrospective data on clinical presentation, genetics, and outcome of HSCT were collected from centers in Europe, Asia, and North America for a total of 32 patients born between 1982 and 2011. Age at presentation was <4 weeks in 30 of 32 patients (94%). Grafts originated from mismatched family donors in 17 patients (55%), from matched family donors in 6 patients (19%), and from unrelated marrow or umbilical cord blood donors in 8 patients (26%). Thirteen patients received secondary or tertiary transplants. After transplantation, 21 of 31 patients were reported alive at a mean follow-up of 7.9 years (range: 0.6-23.6 years). All patients who died beyond 6 months after HSCT had persistent or recurrent agranulocytosis due to failure of donor myeloid engraftment. In the absence of conditioning, HSCT was ineffective to overcome agranulocytosis, and inclusion of myeloablative components in the conditioning regimens was required to achieve stable lymphomyeloid engraftment. In comparison with other SCID entities, considerable differences were noted regarding age at presentation, onset, and type of infectious complications, as well as the requirement of conditioning prior to HSCT. Although long-term survival is possible in the presence of mixed chimerism, high-level donor myeloid engraftment should be targeted to avoid posttransplant neutropenia.

Transplante de Células-Tronco de Sangue do Cordão Umbilical , Transplante de Células-Tronco Hematopoéticas , Leucopenia/mortalidade , Leucopenia/terapia , Imunodeficiência Combinada Severa/mortalidade , Imunodeficiência Combinada Severa/terapia , Condicionamento Pré-Transplante , Doadores não Relacionados , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Adolescente , Adulto , Idade de Início , Aloenxertos , Criança , Intervalo Livre de Doença , Feminino , Humanos , Leucopenia/enzimologia , Leucopenia/genética , Masculino , Imunodeficiência Combinada Severa/enzimologia , Imunodeficiência Combinada Severa/genética , Taxa de Sobrevida
Hum Mutat ; 37(3): 257-68, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26615982


Immunodeficiency patients with DNA repair defects exhibit radiosensitivity and proneness to leukemia/lymphoma formation. Though progress has been made in identifying the underlying mutations, in most patients the genetic basis is unknown. Two de novo mutated candidate genes, MCM3AP encoding germinal center-associated nuclear protein (GANP) and POMP encoding proteasome maturation protein (POMP), were identified by whole-exome sequencing (WES) and confirmed by Sanger sequencing in a child with complex phenotype displaying immunodeficiency, genomic instability, skin changes, and myelodysplasia. GANP was previously described to promote B-cell maturation by nuclear targeting of activation-induced cytidine deaminase (AID) and to control AID-dependent hyperrecombination. POMP is required for 20S proteasome assembly and, thus, for efficient NF-κB signaling. Patient-derived cells were characterized by impaired homologous recombination, moderate radio- and cross-linker sensitivity associated with accumulation of damage, impaired DNA damage-induced NF-κB signaling, and reduced nuclear AID levels. Complementation by wild-type (WT)-GANP normalized DNA repair and WT-POMP rescued defective NF-κB signaling. In conclusion, we identified for the first time mutations in MCM3AP and POMP in an immunodeficiency patient. These mutations lead to cooperative effects on DNA recombination and damage signaling. Digenic/polygenic mutations may constitute a novel genetic basis in immunodeficiency patients with DNA repair defects.

Acetiltransferases/genética , Dano ao DNA/genética , Reparo do DNA/genética , Síndromes de Imunodeficiência/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Chaperonas Moleculares/genética , Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Humanos , Mutação/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia