scholarly journals Bringing natural killer cells to the clinic: ex vivo manipulation

Hematology ◽  
2013 ◽  
Vol 2013 (1) ◽  
pp. 234-246 ◽  
Author(s):  
Richard W. Childs ◽  
Maria Berg

Abstract Recently, there has been a substantial gain in our understanding of the role that natural killer (NK) cells play in mediating innate host immune responses against viruses and cancer. Although NK cells have long been known to be capable of killing cancer cells independently of antigen recognition, the full therapeutic potential of NK cell–based immunotherapy has yet to be realized. Here we review novel methods to activate and expand human NK cells ex vivo for adoptive transfer in humans, focusing on the important phenotypic and functional differences observed among freshly isolated, cytokine activated, and ex vivo–expanded NK populations.

Hematology ◽  
2013 ◽  
Vol 2013 (1) ◽  
pp. 247-253 ◽  
Author(s):  
Jeffrey S. Miller

Abstract Natural killer (NK) cells recognize targets stressed by malignant transformation or infection (particularly CMV). We now know that NK cells can be long-lived and remember past exposures. They become educated by interaction with MHC class I molecules to gain potent function to kill targets and produce cytokines. In the clinical setting, haploidentical NK cells can be transferred adoptively to treat cancer. Persistence and in vivo expansion of NK cells depends on lymphodepleting chemotherapy to make space for the release of endogenous IL-15. In vivo expansion is also enhanced by cytokine administration. IL-2 has been used at low doses to stimulate NK cells in vivo, but has the down side of stimulating CD25hi regulatory T cells. IL-15 is now being tested and has the advantage of avoiding inhibitory regulatory T cell stimulation. In refractory acute myeloid leukemia, leukemia clearance is correlated with the persistence and in vivo expansion of NK cells after adoptive transfer. Limitations to NK cell therapy include poor in vivo survival and lack of specificity. Monoclonal antibodies and bispecific or trispecific killer engagers to target CD16 on NK cells to enhance recognition of various tumor antigens and ADAM17 inhibition to prevent CD16 shedding after NK cell activation should promote enhanced killing of cancer with specificity. Future strategies to exploit favorable donor immunogenetics or to expand NK cells ex vivo from blood, progenitors, or pluripotent progenitors may overcome immune barriers of adoptive transfer and comparative clinical trials will be needed to test these approaches.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2664-2664
Author(s):  
Lisa M. Kopp ◽  
Cecele J. Denman ◽  
Shiguo Zhu ◽  
Dean A. Lee

Abstract Abstract 2664 Poster Board II-640 Adoptive transfer of activated autologous or allogeneic natural killer (NK) cells has emerged as a safe and potentially efficacious immunotherapy for cancer. Alloreactive HLA haploidentical NK cells in the HSCT setting have been reported to enhance engraftment, reduce GVHD and prevent relapse of leukemia. The main restrictions to developing NK cells for immunotherapy are the limited quantity of cells available for adoptive transfer and the modulation of NK cell receptors and/or NK cell ligands as a recognized mechanism of immune escape in oncogenesis. To address the first hurdle, we have developed an efficient method to expand CD3−CD56+ primary NK cells in vitro using K562 artificial APCs expressing membrane-bound IL-21. Altering the balance of activating and inhibitory signals with immunosensitizing drugs is an attractive approach to addressing the second hurdle of NK cell therapy. DNA methylation inhibitors such as 5-Aza-2'-deoxycytidine and 5-azacytidine are being tested for their activity in AML, and have been shown to sensitize AML blasts to lysis by NK cells. However, there is little information on the direct immunologic effect of these hypomethylating agents on NK cell function, reconstitution, and phenotype. Using the calcein release assay, we investigated NK cell survival and lytic function against the NK cell-sensitive HLAnull 721.221 cells after exposing expanded NK cells to 5-Aza-2'-deoxycytidine. Human peripheral blood NK cells that had been expanded ex vivo in our laboratory were incubated with a wide range of 5-Aza-2'-deoxycytidine concentrations for 3 days in the presence of 50 IU/mL IL-2. Cell viability was tested every 24 h. We found that 5-Aza-2'-deoxycytidine at higher concentrations resulted in reduced NK cell viability, but at lower concentrations inhibited NK cell killing. At these lower doses, NK cell inhibition was not associated with loss of viability, resulting in an overall U-shaped dose response curve to 5-Aza-2'-deoxycytidine with maximum inhibition in the 0.3 – 2.5 micromolar range. This biphasic response to 5-Aza-2'-deoxycytidine matches that previously described for malignant cells in which reduced proliferation at higher concentrations resulted in reduced demethylation inhibition (Qin et al, Clin Cancer Res. 2007 Jul 15;13(14):4225–32). To assess the role of demethylation in NK cells in a more dynamic setting, we are investigating 5-Aza-2'-deoxycytidine effects on NK cell proliferation and phenotype during ex vivo expansion, and assessing NK cell recovery, phenotype, and function in a prospective cross-over trial of patients receiving 5-azacytidine post HSCT. Disclosures: No relevant conflicts of interest to declare.


Author(s):  
Leoni Rolfes ◽  
Tobias Ruck ◽  
Christina David ◽  
Stine Mencl ◽  
Stefanie Bock ◽  
...  

AbstractRag1−/− mice, lacking functional B and T cells, have been extensively used as an adoptive transfer model to evaluate neuroinflammation in stroke research. However, it remains unknown whether natural killer (NK) cell development and functions are altered in Rag1−/− mice as well. This connection has been rarely discussed in previous studies but might have important implications for data interpretation. In contrast, the NOD-Rag1nullIL2rgnull (NRG) mouse model is devoid of NK cells and might therefore eliminate this potential shortcoming. Here, we compare immune-cell frequencies as well as phenotype and effector functions of NK cells in Rag1−/− and wildtype (WT) mice using flow cytometry and functional in vitro assays. Further, we investigate the effect of Rag1−/− NK cells in the transient middle cerebral artery occlusion (tMCAO) model using antibody-mediated depletion of NK cells and adoptive transfer to NRG mice in vivo. NK cells in Rag1−/− were comparable in number and function to those in WT mice. Rag1−/− mice treated with an anti-NK1.1 antibody developed significantly smaller infarctions and improved behavioral scores. Correspondingly, NRG mice supplemented with NK cells were more susceptible to tMCAO, developing infarctions and neurological deficits similar to Rag1−/− controls. Our results indicate that NK cells from Rag1−/− mice are fully functional and should therefore be considered in the interpretation of immune-cell transfer models in experimental stroke. Fortunately, we identified the NRG mice, as a potentially better-suited transfer model to characterize individual cell subset-mediated neuroinflammation in stroke.


2022 ◽  
Vol 21 (1) ◽  
Author(s):  
Reza Hosseini ◽  
Hamzeh Sarvnaz ◽  
Maedeh Arabpour ◽  
Samira Molaei Ramshe ◽  
Leila Asef-Kabiri ◽  
...  

AbstractTumor-derived exosomes (TDEs) play pivotal roles in several aspects of cancer biology. It is now evident that TDEs also favor tumor growth by negatively affecting anti-tumor immunity. As important sentinels of immune surveillance system, natural killer (NK) cells can recognize malignant cells very early and counteract the tumor development and metastasis without a need for additional activation. Based on this rationale, adoptive transfer of ex vivo expanded NK cells/NK cell lines, such as NK-92 cells, has attracted great attention and is widely studied as a promising immunotherapy for cancer treatment. However, by exploiting various strategies, including secretion of exosomes, cancer cells are able to subvert NK cell responses. This paper reviews the roles of TDEs in cancer-induced NK cells impairments with mechanistic insights. The clinical significance and potential approaches to nullify the effects of TDEs on NK cells in cancer immunotherapy are also discussed.


Vaccines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1363
Author(s):  
Elena V. Abakushina ◽  
Liubov I. Popova ◽  
Andrey A. Zamyatnin ◽  
Jens Werner ◽  
Nikolay V. Mikhailovsky ◽  
...  

In the last decade, an impressive advance was achieved in adoptive cell therapy (ACT), which has improved therapeutic potential and significant value in promising cancer treatment for patients. The ACT is based on the cell transfer of dendritic cells (DCs) and/or immune effector cells. DCs are often used as vaccine carriers or antigen-presenting cells (APCs) to prime naive T cells ex vivo or in vivo. Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells are used as major tool effector cells for ACT. Despite the fact that NK cell immunotherapy is highly effective and promising against many cancer types, there are still some limitations, including insignificant infiltration, adverse conditions of the microenvironment, the immunosuppressive cellular populations, and the low cytotoxic activity in solid tumors. To overcome these difficulties, novel methods of NK cell isolation, expansion, and stimulation of cytotoxic activity should be designed. In this review, we discuss the basic characteristics of DC vaccines and NK cells as potential adoptive cell preparations in cancer therapy.


Blood ◽  
2009 ◽  
Vol 114 (19) ◽  
pp. 4081-4088 ◽  
Author(s):  
Ting Zhang ◽  
Shuxun Liu ◽  
Pengyuan Yang ◽  
Chaofeng Han ◽  
Jianli Wang ◽  
...  

Abstract Tissue microenvironment and stroma-derived extracellular matrix (ECM) molecules play important roles in the survival and differentiation of cells. Mouse natural killer (NK) cells usually die within 24 hours once isolated ex vivo. Exogenous cytokines such as interleukin-12 (IL-12) and IL-15 are required to maintain the survival and activity of mouse NK cells cultured in vitro. Whether and how ECM molecules such as fibronectin can support the survival of NK cells remain unknown. We demonstrate that fibronectin, just like IL-15, can maintain survival of mouse NK cells in vitro. Furthermore, we show that fibronectin binds to the CD11b on NK cells, and then CD11b recruits and activates Src. Src can directly interact with β-catenin and trigger nuclear translocation of β-catenin. The activation of β-catenin promotes extracellular signal-related kinase (ERK) phosphorylation, resulting in the increased expression of antiapoptotic protein B-cell leukemia 2 (Bcl-2), which may contribute to the maintenance of NK-cell survival. Consistently, fibronectin cannot maintain the survival of CD11b− NK cells and β-catenin–deficient NK cells in vitro, and the number of NK cells is dramatically decreased in the β-catenin–deficient mice. Therefore, fibronectin can maintain survival of mouse NK cells by activating ERK and up-regulating Bcl-2 expression via CD11b/Src/β-catenin pathway.


Cancers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2417 ◽  
Author(s):  
Tram N. Dao ◽  
Sagar Utturkar ◽  
Nadia Atallah Lanman ◽  
Sandro Matosevic

Among natural killer (NK) cell receptors, the T-cell immunoglobulin and mucin-containing domain (TIM-3) has been associated with both inhibitory and activating functions, depending on context and activation pathway. Ex vivo and in vitro, expression of TIM-3 is inducible and depends on activation stimulus. Here, we report that TIM-3 expression can be downregulated on NK cells under specific conditions. When NK cells are exposed to cancer targets, they synergize with stimulation conditions to induce a substantial decrease in TIM-3 expression on their surface. We found that such downregulation occurs following prior NK activation. Downregulated TIM-3 expression correlated to lower cytotoxicity and lower interferon gamma (IFN-γ) expression, fueling the notion that TIM-3 might function as a benchmark for human NK cell dysfunction.


Cancers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 926 ◽  
Author(s):  
Stefania Mantovani ◽  
Barbara Oliviero ◽  
Stefania Varchetta ◽  
Dalila Mele ◽  
Mario U. Mondelli

Hepatocellular carcinoma (HCC) still represents a significant complication of chronic liver disease, particularly when cirrhosis ensues. Current treatment options include surgery, loco-regional procedures and chemotherapy, according to specific clinical practice guidelines. Immunotherapy with check-point inhibitors, aimed at rescuing T-cells from exhaustion, has been applied as second-line therapy with limited and variable success. Natural killer (NK) cells are an essential component of innate immunity against cancer and changes in phenotype and function have been described in patients with HCC, who also show perturbations of NK activating receptor/ligand axes. Here we discuss the current status of NK cell treatment of HCC on the basis of existing evidence and ongoing clinical trials on adoptive transfer of autologous or allogeneic NK cells ex vivo or after activation with cytokines such as IL-15 and use of antibodies to target cell-expressed molecules to promote antibody-dependent cellular cytotoxicity (ADCC). To this end, bi-, tri- and tetra-specific killer cell engagers are being devised to improve NK cell recognition of tumor cells, circumventing tumor immune escape and efficiently targeting NK cells to tumors. Moreover, the exciting technique of chimeric antigen receptor (CAR)-engineered NK cells offers unique opportunities to create CAR-NK with multiple specificities along the experience gained with CAR-T cells with potentially less adverse effects.


2016 ◽  
Vol 90 (6) ◽  
pp. 3123-3137 ◽  
Author(s):  
Kevin C. Chen ◽  
Richard J. Stanton ◽  
Jareer J. Banat ◽  
Mark R. Wills

ABSTRACTImmune responses of natural killer (NK) cell are controlled by the balance between activating and inhibitory receptors, but the expression of these receptors varies between cells within an individual. Although NK cells are a component of the innate immune system, particular NK cell subsets expressing Ly49H are positively selected and increase in frequency in response to cytomegalovirus infection in mice. Recent evidence suggests that in humans certain NK subsets also have an increased frequency in the blood of human cytomegalovirus (HCMV)-infected individuals. However, whether these subsets differ in their capacity of direct control of HCMV-infected cells remains unclear. In this study, we developed a novelin vitroassay to assess whether human NK cell subsets have differential abilities to inhibit HCMV growth and dissemination. NK cells expressing or lacking NKG2C did not display any differences in controlling viral dissemination. However, whenin vitro-expanded NK cells were used, cells expressing or lacking the inhibitory receptor leukocyte immunoglobulin-like receptor 1 (LIR1) were differentially able to control dissemination. Surprisingly, the ability of LIR1+NK cells to control virus spread differed between HCMV viral strains, and this phenomenon was dependent on amino acid sequences within the viral ligand UL18. Together, the results here outline anin vitrotechnique to compare the long-term immune responses of different human NK cell subsets and suggest, for the first time, that phenotypically defined human NK cell subsets may differentially recognize HCMV infections.IMPORTANCEHCMV infection is ubiquitous in most populations; it is not cleared by the host after primary infection but persists for life. The innate and adaptive immune systems control the spread of virus, for which natural killer (NK) cells play a pivotal role. NK cells can respond to HCMV infection by rapid, short-term, nonspecific innate responses, but evidence from murine studies suggested that NK cells may display long-term, memory-like responses to murine cytomegalovirus infection. In this study, we developed a new assay that examines human NK cell subsets that have been suggested to play a long-term memory-like response to HCMV infection. We show that changes in an HCMV viral protein that interacts with an NK cell receptor can change the ability of NK cell subsets to control HCMV while the acquisition of another receptor has no effect on virus control.


Blood ◽  
2011 ◽  
Vol 118 (9) ◽  
pp. 2473-2482 ◽  
Author(s):  
Catharina H. M. J. Van Elssen ◽  
Joris Vanderlocht ◽  
Tammy Oth ◽  
Birgit L. M. G. Senden-Gijsbers ◽  
Wilfred T. V. Germeraad ◽  
...  

Abstract Among prostaglandins (PGs), PGE2 is abundantly expressed in various malignancies and is probably one of many factors promoting tumor growth by inhibiting tumor immune surveillance. In the current study, we report on a novel mechanism by which PGE2 inhibits in vitro natural killer–dendritic cell (NK-DC) crosstalk and thereby innate and adaptive immune responses via its effect on NK-DC crosstalk. The presence of PGE2 during IFN-γ/membrane fraction of Klebsiella pneumoniae DC maturation inhibits the production of chemokines (CCL5, CCL19, and CXCL10) and cytokines (IL-12 and IL-18), which is cAMP-dependent and imprinted during DC maturation. As a consequence, these DCs fail to attract NK cells and show a decreased capacity to trigger NK cell IFN-γ production, which in turn leads to reduced T-helper 1 polarization. In addition, the presence of PGE2 during DC maturation impairs DC-mediated augmentation of NK-cell cytotoxicity. Opposed to their inhibitory effects on peripheral blood–derived NK cells, PGE2 matured DCs induce IL-22 secretion of inflammation constraining NKp44+ NK cells present in mucosa-associated lymphoid tissue. The inhibition of NK-DC interaction is a novel regulatory property of PGE2 that is of possible relevance in dampening immune responses in vivo.


Sign in / Sign up

Export Citation Format

Share Document