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1.
Front Immunol ; 10: 1876, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447858

RESUMO

High risk Neuroblastoma (NB) includes aggressive, metastatic solid tumors of childhood. The survival rate improved only modestly, despite the use of combination therapies including novel immunotherapies based on the antibody-mediated targeting of tumor-associated surface ligands. Treatment failures may be due to the lack of adequate in vitro models for studying, in a given patient, the efficacy of potential therapeutics, including those aimed to enhance anti-tumor immune responses. We here propose a 3D alginate-based hydrogel as extracellular microenvironment to evaluate the effects of the three-dimensionality on biological and immunological properties of NB cells. NB cell lines grown within the 3D alginate spheres presented spheroid morphology, optimal survival, and proliferation capabilities, and a reduced sensitivity to the cytotoxic effect of imatinib mesylate. 3D cultured NB cells were also evaluated for the constitutive and IFN-γ-induced expression of surface molecules capable of tuning the anti-tumor activity of NK cells including immune checkpoint ligands. In particular, IFN-γ induced de novo expression of high amounts of HLA-I molecules, which protected NB cells from the attack mediated by KIR/KIR-L matched NK cells. Moreover, in the 3D alginate spheres, the cytokine increased the expression of the immune checkpoint ligands PD-Ls and B7-H3 while virtually abrogating that of PVR, a ligand of DNAM-1 activating receptor, whose expression correlates with high susceptibility to NK-mediated killing. Our 3D model highlighted molecular features that more closely resemble the immunophenotypic variants occurring in vivo and not fully appreciated in classical 2D culture conditions. Thus, based on our results, 3D alginate-based hydrogels might represent a clinical-relevant cell culture platform where to test the efficacy of personalized therapeutic approaches aimed to optimize the current and innovative immune based therapies in a very systematic and reliable way.

2.
Front Immunol ; 10: 1415, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316503

RESUMO

Natural killer (NK) cells were originally defined as effector lymphocytes of innate immunity characterized by the unique ability of killing tumor and virally infected cells without any prior priming and expansion of specific clones. The "missing-self" theory, proposed by Klas Karre, the seminal discovery of the first prototypic HLA class I-specific inhibitory receptors, and, later, of the Natural Cytotoxicity Receptors (NCRs) by Alessandro Moretta, provided the bases to understand the puzzling behavior of NK cells. Actually, those discoveries proved crucial also for many of the achievements that, along the years, have contributed to the modern view of these cells. Indeed, NK cells, besides killing susceptible targets, are now known to functionally interact with different immune cells, sense pathogens using TLR, adapt their responses to the local environment, and, even, mount a sort of immunological memory. In this review, we will specifically focus on the main activating NK receptors and on their crucial role in the ever-increasing number of functions assigned to NK cells and other innate lymphoid cells (ILCs).

3.
HLA ; 94(2): 100-110, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31177639

RESUMO

The Eleventh Killer Immunoglobulin-like Receptor (KIR) Workshop was held in Camogli (Genoa, Italy) in October 2018. This congress brought together 113 participants working on KIR field. Fifty-eight studies have been presented, the majority of which included unpublished data. Thus, KIR workshop, allowing the meeting of people sharing their knowledge and experience in a friendly atmosphere, still represents a special event of fruitful discussion and exchange of novel breakthrough, results, and ideas. In this report, we summarize all the scientific contributions highlighting the most recent advances in KIR field. Forty abstracts presented at the KIR Workshop are published in this issue.

5.
Front Immunol ; 10: 1179, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31231370

RESUMO

Natural killer (NK) cells contribute to the first line of defense against viruses and to the control of tumor growth and metastasis spread. The discovery of HLA class I specific inhibitory receptors, primarily of killer Ig-like receptors (KIRs), and of activating receptors has been fundamental to unravel NK cell function and the molecular mechanisms of tumor cell killing. Stemmed from the seminal discoveries in early '90s, in which Alessandro Moretta was the major actor, an extraordinary amount of research on KIR specificity, genetics, polymorphism, and repertoire has followed. These basic notions on NK cells and their receptors have been successfully translated to clinical applications, primarily to the haploidentical hematopoietic stem cell transplantation to cure otherwise fatal leukemia in patients with no HLA compatible donors. The finding that NK cells may express the PD-1 inhibitory checkpoint, particularly in cancer patients, may allow understanding how anti-PD-1 therapy could function also in case of HLA class Ineg tumors, usually susceptible to NK-mediated killing. This, together with the synergy of therapeutic anti-checkpoint monoclonal antibodies, including those directed against NKG2A or KIRs, emerging in recent or ongoing studies, opened new solid perspectives in cancer therapy.

6.
HLA ; 93(4): 185-194, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30828978

RESUMO

Natural killer (NK) cells are innate immune effector cells involved in the first line of defense against viral infections and malignancies. In the last three decades, the identification of HLA class I-specific inhibitory killer immunoglobulin-like receptors (KIR) and of the main activating receptors has strongly improved our understanding of the mechanisms regulating NK cell functions. The increased knowledge on how NK cells discriminate healthy cells from damaged cells has made it possible to transfer basic research notions to clinical applications. Of particular relevance is the strong NK-mediated anti-leukemia effect in haploidentical hematopoietic stem cell transplantation to cure high-risk leukemia.

7.
Clin Immunol ; 2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30391652

RESUMO

X-linked lymphoproliferative disease 1 (XLP1) is a monogenic disorder caused by mutations in SH2D1A, resulting in the absence/dysfunction of the signaling lymphocyte activation molecule (SLAM)-associated protein (SAP). Consequently, SLAM receptors as 2B4 (CD244) and NTB-A (SLAMF6), upon ligand engagement, exert inhibitory instead of activating function. This causes an immune dysfunction that is worsened by the selective inability of NK and T cells to kill EBV-infected B cells with dramatic clinical sequelae (e.g. fulminant mononucleosis, hyperinflammation, lymphoma). Here we outline recent findings on the interplay between inhibitory 2B4 and the various activating receptors in NK cells. 2B4 engagement selectively blocks ITAM-dependent activating receptors as NCR and CD16, while it does not affect NKG2D and DNAM-1. Furthermore, inhibitory 2B4 participates to NK cell education, as highlighted by the existence in XLP1 patients of a large subset of fully functional NK cells that lack self-HLA specific inhibitory receptors and exert autoreactivity against mature dendritic cells.

8.
J Immunol ; 201(7): 2028-2041, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30120122

RESUMO

Cross-talk between NK cells and dendritic cells (DCs) is important in Th1 immune responses, including antitumor immunity and responses to infections. DCs also play a crucial role in polarizing Th2 immunity, but the impact of NK cell-DC interactions in this context remains unknown. In this study, we stimulated human monocyte-derived DCs in vitro with different pathogen-associated molecules: LPS or polyinosinic-polycytidylic acid, which polarize a Th1 response, or soluble egg Ag from the helminth worm Schistosoma mansoni, a potent Th2-inducing Ag. Th2-polarizing DCs were functionally distinguishable from Th1-polarizing DCs, and both showed distinct morphology and dynamics from immature DCs. We then assessed the outcome of autologous NK cells interacting with these differently stimulated DCs. Confocal microscopy showed polarization of the NK cell microtubule organizing center and accumulation of LFA-1 at contacts between NK cells and immature or Th2-polarizing DCs but not Th1-polarizing DCs, indicative of the assembly of an activating immune synapse. Autologous NK cells lysed immature DCs but not DCs treated with LPS or polyinosinic-polycytidylic acid as reported previously. In this study, we demonstrated that NK cells also degranulated in the presence of Th2-polarizing DCs. Moreover, time-lapse live-cell microscopy showed that DCs that had internalized fluorescently labeled soluble egg Ag were efficiently lysed. Ab blockade of NK cell-activating receptors NKp30 or DNAM-1 abrogated NK cell lysis of Th2-polarizing DCs. Thus, these data indicate a previously unrecognized role of NK cell cytotoxicity and NK cell-activating receptors NKp30 and DNAM-1 in restricting the pool of DCs involved in Th2 immune responses.

9.
J Immunol ; 201(5): 1460-1467, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068594

RESUMO

Four killer cell Ig-like receptor (KIR) genes, collectively referred to as framework genes, characterize almost all KIR haplotypes. In particular, KIR3DL3 and KIR3DL2 mark the ends of the locus, whereas KIR3DP1 and KIR2DL4 are located in the central part. A recombination hot spot, mapped between KIR3DP1 and KIR2DL4, splits the haplotypes into two regions: a centromeric (Cen) region (spanning from KIR3DL3 to KIR3DP1) and a telomeric region (from KIR2DL4 to KIR3DL2), both varying in KIR gene content. In this study, we analyzed KIR3DP1 polymorphism in a cohort of 316 healthy, unrelated individuals. To this aim, we divided KIR3DP1 alleles into two groups by the use of a sequence-specific primer- PCR approach. Our data clearly indicated that KIR3DP1 alleles present on haplotypes carrying Cen-A or Cen-B1 regions differ from those having Cen-B2 motifs. Few donors (∼3%) made exceptions, and they were all, except one, characterized by uncommon haplotypes, including either KIR deletions or KIR duplications. Consequently, as KIR2DL1 is present in Cen-A and Cen-B1 regions but absent in Cen-B2 regions, we demonstrated that KIR3DP1 polymorphism might represent a suitable marker for KIR2DL1 gene copy number analysis. Moreover, because Cen-B1 and Cen-B2 regions are characterized by different KIR3DP1 alleles, we showed that KIR3DP1 polymorphism analysis also provides information to dissect between Cen-B1/Cen-B1 and Cen-B1/Cen-B2 donors. Taken together, our data suggest that the analysis of KIR3DP1 polymorphism should be included in KIR repertoire evaluation.

10.
Trends Immunol ; 39(7): 577-590, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29793748

RESUMO

Natural killer (NK) cells are involved in innate defenses against viruses and tumors. Their function is finely tuned by activating and inhibitory receptors. Among the latter, killer immunoglobulin-like receptors and CD94/NKG2A recognize human leukocyte antigen (HLA) Class I molecules, allowing NK cells to discriminate between normal and aberrant cells, as well as to recognize allogeneic cells, because of their ability to sense HLA polymorphisms. This latter phenomenon plays a key role in HLA-haploidentical hematopoietic stem cell transplantation (haplo-HSCT) for high-risk acute leukemia patients transplanted from an NK-alloreactive donor. Different haplo-HSCT settings have been developed, either T depleted or T replete - the latter requiring graft-versus-host disease prophylaxis. A novel graft manipulation, based on depletion of αß T cells and B cells, allows infusion of fully mature, including alloreactive, NK cells. The excellent patient clinical outcome underscores the importance of these innate cells in cancer therapy.

11.
Clin Cancer Res ; 24(4): 870-881, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29217528

RESUMO

Purpose: T cells infiltrating follicular lymphoma (FL) tumors are considered dysfunctional, yet the optimal target for immune checkpoint blockade is unknown. Characterizing coinhibitory receptor expression patterns and signaling responses in FL T-cell subsets might reveal new therapeutic targets.Experimental Design: Surface expression of 9 coinhibitory receptors governing T-cell function was characterized in T-cell subsets from FL lymph node tumors and from healthy donor tonsils and peripheral blood samples, using high-dimensional flow cytometry. The results were integrated with T-cell receptor (TCR)-induced signaling and cytokine production. Expression of T-cell immunoglobulin and ITIM domain (TIGIT) ligands was detected by immunohistochemistry.Results: TIGIT was a frequently expressed coinhibitory receptor in FL, expressed by the majority of CD8 T effector memory cells, which commonly coexpressed exhaustion markers such as PD-1 and CD244. CD8 FL T cells demonstrated highly reduced TCR-induced phosphorylation (p) of ERK and reduced production of IFNγ, while TCR proximal signaling (p-CD3ζ, p-SLP76) was not affected. The TIGIT ligands CD112 and CD155 were expressed by follicular dendritic cells in the tumor microenvironment. Dysfunctional TCR signaling correlated with TIGIT expression in FL CD8 T cells and could be fully restored upon in vitro culture. The costimulatory receptor CD226 was downregulated in TIGIT+ compared with TIGIT- CD8 FL T cells, further skewing the balance toward immunosuppression.Conclusions: TIGIT blockade is a relevant strategy for improved immunotherapy in FL. A deeper understanding of the interplay between coinhibitory receptors and key T-cell signaling events can further assist in engineering immunotherapeutic regimens to improve clinical outcomes of cancer patients. Clin Cancer Res; 24(4); 870-81. ©2017 AACR.

12.
Int J Hyperthermia ; 34(4): 469-478, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28705098

RESUMO

RATIONALE: Hyperthermic isolated lung Perfusion (ILuP) is used to deliver high-dose chemotherapy to pulmonary metastases while sparing systemic toxicity. Accurate leakage monitoring is however necessary. This study aimed to verify the accuracy of radionuclide leakage monitoring in patients undergoing ILuP, by comparing this method with serial blood sampling. METHODS: A total of 15 consecutive ILuP procedures were performed on eleven patients affected by lung metastases from soft tissue sarcoma. After establishing isolated perfusion, erythrocytes of systemic blood (SB) were labelled with 0.2 MBq/kg of 99mTc. The baseline SB counting rate (CR) was assessed using a γ-probe. Subsequently, erythrocytes of the circuit blood (CB) were labelled with 2 Mbq/kg of 99mTc. Radioactivity leakage factor (RLF) was continuously measured using a formula, accounting for CR, systemic/circuit activity ratio and total/systemic volume ratio. The TNF-α concentration in SB and CB was measured by enzymelinked immunosorbent assay (ELISA) throughout the procedure. RESULTS: RLF averaged 2.3 ± 1.5%, while the systemic/circuit TNF-α ratio was 0.05 ± 0.12%. These two indices were strictly correlated in all of the procedures (average Rvalue 0.88 ± 0.07). RLF exceeded 5% during three of 15 procedures, prompting the application of compensatory manoeuvres. ELISA confirmed a marked increase in systemic TNF-α levels in these patients (2.6 ± 3.5 ng/ml). Conversely, patients whose RLF did not exceed the 5% threshold presented a mean TNF-α of 0.02 ± 0.005 ng/ml (p < 0.01). CONCLUSIONS: In patients submitted to ILuP, RLF monitoring is feasible and accurate. Moreover, it grants immediate results, permitting for the adoption of corrective manoeuvres for leakage, thus minimising toxicity.

14.
Blood ; 130(5): 677-685, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28588018

RESUMO

Allogeneic hematopoietic stem cell transplantation (HSCT) from an HLA-haploidentical relative (haplo-HSCT) is a suitable option for children with acute leukemia (AL) either relapsed or at high-risk of treatment failure. We developed a novel method of graft manipulation based on negative depletion of αß T and B cells and conducted a prospective trial evaluating the outcome of children with AL transplanted with this approach. Eighty AL children, transplanted between September 2011 and September 2014, were enrolled in the trial. All children were given a fully myeloablative preparative regimen. Anti-T-lymphocyte globulin from day -5 to -3 was used for preventing graft rejection and graft-versus-host disease (GVHD); no patient received any posttransplantation GVHD prophylaxis. Two children experienced primary graft failure. The cumulative incidence of skin-only, grade 1-2 acute GVHD was 30%; no patient developed extensive chronic GVHD. Four patients died, the cumulative incidence of nonrelapse mortality being 5%, whereas 19 relapsed, resulting in a 24% cumulative incidence of relapse. With a median follow-up of 46 months for surviving patients, the 5-year probability of chronic GVHD-free, relapse-free survival (GRFS) is 71%. Total body irradiation-containing preparative regimen was the only variable favorably influencing relapse incidence and GRFS. The outcomes of these 80 patients are comparable to those of 41 and 51 children given transplantation from an HLA-identical sibling or a 10/10 allelic-matched unrelated donor in the same period. These data indicate that haplo-HSCT after αß T- and B-cell depletion represents a competitive alternative for children with AL in need of urgent allograft. This trial was registered at www.clinicaltrials.gov as #NCT01810120.


Assuntos
Linfócitos B , Transplante de Células-Tronco Hematopoéticas , Leucemia , Depleção Linfocítica , Receptores de Antígenos de Linfócitos T alfa-beta , Linfócitos T , Doença Aguda , Adolescente , Adulto , Aloenxertos , Soro Antilinfocitário/administração & dosagem , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Lactente , Leucemia/mortalidade , Leucemia/terapia , Masculino , Taxa de Sobrevida
15.
Eur J Immunol ; 47(6): 1051-1061, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28386908

RESUMO

X-linked lymphoproliferative disease 1 (XLP1) is an inherited immunodeficiency, caused by mutations in SH2D1A encoding Signaling Lymphocyte Activation Molecule (SLAM)-associated protein (SAP). In XLP1, 2B4, upon engagement with CD48, has inhibitory instead of activating function. This causes a selective inability of cytotoxic effectors to kill EBV-infected cells, with dramatic clinical sequelae. Here, we investigated the NK cell education in XLP1, upon characterization of killer Ig-like receptor (KIR)/KIR-L genotype and phenotypic repertoire of self-HLA class I specific inhibitory NK receptors (self-iNKRs). We also analyzed NK-cell cytotoxicity against CD48+ or CD48- KIR-ligand matched or autologous hematopoietic cells in XLP1 patients and healthy controls. XLP1 NK cells may show a defective phenotypic repertoire with substantial proportion of cells lacking self-iNKR. These NK cells are cytotoxic and the inhibitory 2B4/CD48 pathway plays a major role to prevent killing of CD48+ EBV-transformed B cells and M1 macrophages. Importantly, self-iNKR defective NK cells kill CD48- targets, such as mature DCs. Self-iNKR- NK cells in XLP1 patients are functional even in resting conditions, suggesting a role of the inhibitory 2B4/CD48 pathway in the education process during NK-cell maturation. Killing of autologous mature DC by self-iNKR defective XLP1 NK cells may impair adaptive responses, further exacerbating the patients' immune defect.


Assuntos
Células Matadoras Naturais/imunologia , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/fisiopatologia , Receptores de Células Matadoras Naturais/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo , Antígeno CD48/imunologia , Antígeno CD48/metabolismo , Genes MHC Classe I , Humanos , Células Matadoras Naturais/metabolismo , Ativação Linfocitária , Canais de Potássio Corretores do Fluxo de Internalização/imunologia , Receptores Imunológicos/metabolismo , Transdução de Sinais , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária/metabolismo , Família de Moléculas de Sinalização da Ativação Linfocitária/imunologia
16.
J Immunol ; 198(7): 2556-2567, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28202613

RESUMO

The functions of activating members of the killer cell Ig-like receptor (KIR) family are not fully understood, as the ligands for these receptors are largely unidentified. In this study, we report that KIR2DS2 reporter cells recognize a ligand expressed by cancer cell lines. All cancer targets recognized by KIR2DS2 were also recognized by KIR2DL2 and KIR2DL3 reporters. Trogocytosis of membrane proteins from the cancer targets was observed with responding reporter cells, indicating the formation of KIR2DS2 ligand-specific immunological synapses. HLA-C typing of target cells showed that KIR2DS2 recognition was independent of the HLA C1 or C2 group, whereas targets cells that were only recognized by KIR2DL3 expressed C1 group alleles. Anti-HLA class I Abs blocked KIR2DL3 responses toward C1-expressing targets, but they did not block KIR2DS2 recognition of cancer cells. Small interfering RNA knockdown of ß2-microglobulin reduced the expression of class I H chain on the cancer targets by >97%, but it did not reduce the KIR2DS2 reporter responses, indicating a ß2-microglobulin-independent ligand for KIR2DS2. Importantly, KIR2DL3 responses toward some KIR2DS2 ligand-expressing cells were also undiminished after ß2-microglobulin knockdown, and they were not blocked by anti-HLA class I Abs, suggesting that KIR2DL3, in addition to the traditional HLA-C ligands, can bind to the same ß2-microglobulin-independent ligand as KIR2DS2. These observations indicate the existence of a novel, presently uncharacterized ligand for the activating NK cell receptor KIR2DS2. Molecular identification of this ligand may lead to improved KIR-HLA mismatching in hematopoietic stem cell transplantation therapy for leukemia and new, more specific NK cell-based cancer therapies.


Assuntos
Neoplasias/metabolismo , Receptores KIR2DL2/metabolismo , Linhagem Celular Tumoral , Separação Celular , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Humanos , Ligantes
17.
Cytometry B Clin Cytom ; 92(2): 100-114, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28054442

RESUMO

Natural killer (NK) cells, the most important effectors of the innate lymphoid cells (ILCs), play a fundamental role in tumor immune-surveillance, defense against viruses and, in general, in innate immune responses. NK cell activation is mediated by several activating receptors and co-receptors able to recognize ligands on virus-infected or tumor cells. To prevent healthy cells from auto-aggression, NK cells are provided with strong inhibitory receptors (KIRs and NKG2A) which recognize HLA class I molecules on target cells and, sensing their level of expression, allow killing of targets underexpressing HLA-class I. In vivo, NK cell-mediated anti-tumor function may be suppressed by tumor or tumor-associated cells via inhibitory soluble factors/cytokines or the engagement of the so called immune-check point molecules (e.g., PD1-PDL1). The study of these immune check-points is now offering new important opportunities for the therapy of cancer. In haemopoietic stem cell transplantation, alloreactive NK cells (i.e., those that express KIRs, which do not recognize HLA class I molecules on patient cells), derived from HSC of haploidentical donors, are able to kill leukemia blasts and patient's DC, thus preventing both tumor relapses and graft-versus-host disease. A clear correlation exists between size of the alloreactive NK cell population and clinical outcome. Thus, in view of the recent major advances in cancer therapy based on immuno-mediated mechanisms, the phenotypic analysis of cells and molecules involved in these mechanisms plays an increasingly major role. © 2017 International Clinical Cytometry Society.


Assuntos
Doença Enxerto-Hospedeiro/patologia , Transplante de Células-Tronco Hematopoéticas , Células Matadoras Naturais/citologia , Leucemia/terapia , Receptores KIR/metabolismo , Animais , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/imunologia , Humanos , Leucemia/imunologia , Fenótipo
18.
Immunol Lett ; 178: 15-9, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27185471

RESUMO

Natural killer (NK) cells play a major role in innate defenses against pathogens, primarily viruses, and are also thought to be part of the immunosurveillance against tumors. They express an array of surface receptors that mediate NK cell function. The human leukocytes antigen (HLA) class I-specific inhibitory receptors allow NK cells to detect and kill cells that have lost or under-express HLA class I antigens, a typical feature of tumor or virally infected cells. However, NK cell activation and induction of cytolytic activity and cytokine production depends on another important checkpoint, namely the expression on target cells of ligands recognized by activating NK receptors. Despite their potent cytolytic activity, NK cells frequently fail to eliminate tumors. This is due to mechanisms of tumor escape, determined by the tumor cells themselves or by tumor-associated cells (i.e. the tumor microenvironment) via the release of soluble suppressive factors or the induction of inhibitory loops involving induction of regulatory T cells, M2-polarized macrophages and myeloid-derived suppressor cells. The most important clinical application involving NK cells is the cure of high-risk leukemias in the haplo-identical hematopoietic stem cell transplant (HSCT) setting. NK cells originated from hematopoietic stem cells (HSC) of HLA-haploidentical donors may express Killer Immunoglobulin-like receptors (KIRs) that are mismatched with the HLA class I alleles of the recipient. This allows NK cells to kill leukemia blasts residual after the conditioning regimen, while sparing normal cells (that do not express ligands for activating NK receptors). More recent approaches based on the specific removal of TCR α/ß(+) T cells and of CD19(+) B cells, allow the infusion, together with CD34(+) HSC, of mature KIR(+) NK cells and of TCR γ/δ(+) T cells, both characterized by a potent anti-leukemia activity. This greatly reduces the time interval necessary to obtain alloreactive, KIR(+) NK cells derived from donor HSC. Another promising approach is based on the use of anti-KIR blocking monoclonal antibodies (mAbs), rendering alloreactive any KIR(+) NK cells.


Assuntos
Imunidade Inata , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Receptores de Células Matadoras Naturais/metabolismo , Transplante de Células-Tronco Hematopoéticas , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunomodulação , Imunoterapia , Células Matadoras Naturais/citologia , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Transplante Homólogo , Microambiente Tumoral/imunologia
19.
Eur J Immunol ; 46(6): 1511-7, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26990677

RESUMO

KIR3DL1 is a natural killer (NK) cell receptor that recognizes the Bw4 epitope of human leukocyte antigen (HLA) class I molecules. Following hematopoietic stem cell transplantation for patients lacking Bw4, KIR3DL1-expressing NK cells from Bw4-positive donors can be alloreactive and eliminate tumor cells. However, KIR3DL1 alleles having T instead of C at nucleotide 320 (encoding leucine 86 instead of serine 86) are not expressed on the cell surface. Thus, not all individuals testing positive for KIR3DL1 are optimal donors for Bw4-negative recipients. Therefore, we developed a method for genotyping codon 86, which was validated by its perfect correlation with NK cell phenotype for 100 donors of diverse KIR3DL1/S1 genotype. We typed 600 donors and found that ∼12.2% had the KIR3DL1 gene, but did not express cell-surface KIR3DL1. By contrast, high-expressing allotypes were identified when haplotypes from four families with duplicated KIR3DL1/S1 genes were characterized at high resolution. Identifying donors who have KIR3DL1 but lack cell-surface KIR3DL1 would refine donor selection. With this technique, the number of individuals identified who may not be optimal donors for Bw4-negative patients increases by threefold, when compared with standard methods. Taken together, we propose that allele typing of killer cell Ig-like receptor (KIR) polymorphisms should become a standard practice when selecting donors.


Assuntos
Códon , Seleção do Doador , Antígenos HLA-B/imunologia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/imunologia , Células-Tronco Hematopoéticas/metabolismo , Receptores KIR3DL1/genética , Receptores KIR3DS1/genética , Alelos , Membrana Celular/metabolismo , Expressão Gênica , Genótipo , Haplótipos , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Modelos Biológicos , Polimorfismo de Nucleotídeo Único , Receptores KIR3DL1/metabolismo , Receptores KIR3DS1/metabolismo , Transplante Homólogo
20.
J Immunother ; 39(2): 90-100, 2016 Feb-Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26849078

RESUMO

Cell-based immunotherapy using donor-derived natural killer (NK) cells after allogeneic hematopoietic stem cell transplantation may be an attractive treatment of residual leukemia. This study aimed to optimize clinical grade production of a cytokine-activated NK-cell product. NK cells were isolated either by double depletion (CD3(-), CD19(-)) or by sequential depletion and enrichment (CD3(-,) CD56(+)) via CliniMACS from leukapheresis material and cultured in vitro with interleukin (IL)-2 or IL-15. Both NK cell isolation procedures yielded comparable recovery of NK cells and levels of T-cell contamination. After culture with cytokines, the CD3(-)CD56(+) procedure resulted in NK cells of higher purity, that is, less T cells and monocytes, higher viability, and a slightly higher yield than the CD3(-)CD19- procedure. CD69, NKp44, and NKG2A expression were higher on CD3(-)CD56(+) products, whereas lysis of Daudi cells was comparable. Five days of culture led to higher expression of CD69, NKp44, and NKp30 and lysis of K562 and Daudi cell lines. Although CD69 expression and lysis of Daudi cells were slightly higher in cultures with IL-2, T-cell contamination was lower with IL-15. Therefore, further experiments were performed with CD3(-)CD56(+) products cultured with IL-15. Cryopreservation of IL-15-activated NK cells resulted in a loss of cytotoxicity (>92%), whereas thawing of isolated, uncultured NK cells followed by culture with IL-15 yielded cells with about 43% of the original lytic activity. Five-day IL-15-activated NK cells lysed tumor target cell lines and primary leukemic blasts, providing the basis for NK cell­based immunotherapeutic strategies in a clinical setting.


Assuntos
Células Matadoras Induzidas por Citocinas/imunologia , Transplante de Células-Tronco Hematopoéticas , Células Matadoras Naturais/imunologia , Leucemia/terapia , Antígenos CD/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Criopreservação , Células Matadoras Induzidas por Citocinas/transplante , Citocinas/metabolismo , Citotoxicidade Imunológica , Humanos , Células Matadoras Naturais/transplante , Leucemia/imunologia
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