技术资料

Mucosal-associated invariant T (MAIT) cells exhibit different characteristics from those of TCRalpha7.2- conventional T cells. They play important roles in various inflammatory diseases,including rheumatoid arthritis and inflammatory bowel disease. MAIT cells express a single T cell receptor alpha chain,TCRalpha7.2 segment associated with Jalpha33 and CDR3 with fixed length,which recognizes bacteria-derived vitamin B metabolites. However,the characteristics of MAIT cells and TCRalpha7.2+ CD161- T cells have never been compared. Here,we performed RNA sequencing to compare the properties of MAIT cells,TCRalpha7.2- conventional T cells and TCRalpha7.2+ CD161- T cells. Genome-wide transcriptomes of MAIT cells,TCRalpha7.2- conventional T cells,and TCRalpha7.2+ CD161- T cells were compared and analyzed using causal network analysis. This is the first report comparing the transcriptomes of MAIT cells,TCRalpha7.2- conventional T cells and TCRalpha7.2+ CD161- T cells. We also identified the predominant signaling pathways of MAIT cells,which differed from those of TCRalpha7.2- conventional T cells and TCRalpha7.2+ CD161- T cells,through a gene set enrichment test and upstream regulator analysis and identified the genes responsible for the characteristic MAIT cell phenotypes. Our study advances the complete understanding of MAIT biology. View Publication

Recent clinical studies suggest that adoptive transfer of donor-derived natural killer (NK) cells may improve clinical outcome in hematological malignancies and some solid tumors by direct anti-tumor effects as well as by reduction of graft versus host disease (GVHD). NK cells have also been shown to enhance transplant engraftment during allogeneic hematopoietic stem cell transplantation (HSCT) for hematological malignancies. The limited ex vivo expansion potential of NK cells from peripheral blood (PB) or umbilical cord blood (UCB) has however restricted their therapeutic potential. Here we define methods to efficiently generate NK cells from donor-matched,full-term human placenta perfusate (termed Human Placenta-Derived Stem Cell,HPDSC) and UCB. Following isolation from cryopreserved donor-matched HPDSC and UCB units,CD56+CD3- placenta-derived NK cells,termed pNK cells,were expanded in culture for up to 3 weeks to yield an average of 1.2 billion cells per donor that were textgreater80% CD56+CD3-,comparable to doses previously utilized in clinical applications. Ex vivo-expanded pNK cells exhibited a marked increase in anti-tumor cytolytic activity coinciding with the significantly increased expression of NKG2D,NKp46,and NKp44 (p textless 0.001,p textless 0.001,and p textless 0.05,respectively). Strong cytolytic activity was observed against a wide range of tumor cell lines in vitro. pNK cells display a distinct microRNA (miRNA) expression profile,immunophenotype,and greater anti-tumor capacity in vitro compared to PB NK cells used in recent clinical trials. With further development,pNK may represent a novel and effective cellular immunotherapy for patients with high clinical needs and few other therapeutic options. View Publication

The serological complement-dependent cytotoxicity crossmatch (CDC-XM) permits routine identification of anti-donor alloantibodies in the sera of allotransplant recipients. However,in a small group of recipients,antibodies below the threshold of detection may still be responsible for hyperacute rejection. For the same reason,approximately 20% of recipients develop acute rejection episodes. The flow cytometry crossmatch (FCXM) was designed to address these problems,but because of the presence of clinically insignificant antibodies (linked,non-lytic),the FCXM appears to be too sensitive yielding false-positive results. We compared FCXM with its modified version assessing cell viability (cytolytic flow cytometry crossmatch; cFCXM) using sera from previously sensitised kidney recipients. The presence of alloantibodies was detected using the Luminex platform. The cFCXM proved to be of greater sensitivity than CDC-XM,which was additionally confirmed with bead-based Luminex techniques. The cFCXM was also superior to FCXM because it distinguished lytic from non-lytic antibodies. The cFCXM was superior to assess donor specificity,sensitivity,and detection of clinically relevant lytic antibodies. View Publication

Multi-parameter flow cytometry analysis of T regulatory (Treg) cells is a widely used approach in basic and translational research studies. This approach has been complicated by a lack of specific markers for Treg cells and lack of uniformity in the quantification of Treg cells. Given the central role of Treg cells in the inception and perpetuation of diverse immune responses as well as its target as a therapeutic,it is imperative to have established methodologies for Treg cell analysis that are robust and usable for studies with multiple subjects as well as multicenter studies. In this study,we describe an optimized multi-parameter flow cytometry protocol for the quantification of human Treg cells from freshly obtained and viably frozen samples and correlations with epigenetic Treg cell analysis (TSDR demethylation). We apply these two methodologies to characterize Treg cell differences between cord blood and adult peripheral blood. In summary,the optimized protocol appears to be robust for Treg cell quantification from freshly isolated or viably frozen cells and the multi-parameter flow cytometry findings are strongly positively correlated with TSDR demethylation thus providing several options for the characterization of Treg cell frequency and function in large translational or clinical studies. View Publication

In this study,we examined the effects of cryoprotectant,freezing and thawing,and adenovirus (Adv) transduction on the viability,transgene expression,phenotype,and function of human dendritic cells (DCs). DCs were differentiated from cultured peripheral blood (PB) monocytes following Elutra isolation using granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) for 6 days and then transduced using an Adv vector with an IL-12 transgene. Fresh,cryopreserved,and thawed transduced immature DCs were examined for their: 1) cellular concentration and viability; 2) antigenicity using an allogeneic mixed lymphocyte reaction (MLR); 3) phenotype (HLA-DR and CD11c) and activation (CD83); and 4) transgene expression based on IL-12 secretion. Stability studies revealed that transduced DCs could be held in cryoprotectant for as long as 75 min at 2-8°C prior to freezing with little effect on their viability and cellularity. Further,cryopreservation,storage,and thawing reduced the viability of the transduced DCs by an average of 7.7%; and had no significant impact on DC phenotype and activation. In summary,cryopreservation,storage,and thawing had no significant effect on DC viability,function,and transgene expression by Adv-transduced DCs. View Publication

BACKGROUND Patients with gene expression profiling-defined high-risk myeloma in relapse have poor outcomes with current therapies. We tested whether natural killer cells expanded by co-culture with K562 cells transfected with 41BBL and membrane-bound interleukin-15 could kill myeloma cells with a high-risk gene expression profile in vitro and in a unique model which recapitulates human myeloma. DESIGN AND METHODS OPM2 and high-risk primary myeloma tumors were grown in human fetal bone implanted into non-obese diabetic severe combined immunodeficiency mice with a deficient interleukin-2 receptor gamma chain. These mice are devoid of endogenous natural killer and T-cell activity and were used to determine whether adoptively transferred expanded natural killer cells could inhibit myeloma growth and myeloma-associated bone destruction. RESULTS Natural killer cells from healthy donors and myeloma patients expanded a median of 804- and 351-fold,respectively,without significant T-cell expansion. Expanded natural killer cells killed both allogeneic and autologous primary myeloma cells avidly via a perforin-mediated mechanism in which the activating receptor NKG2D,natural cytotoxicity receptors,and DNAX-accessory molecule-1 played a central role. Adoptive transfer of expanded natural killer cells inhibited the growth of established OPM2 and high-risk primary myeloma tumors grown in the murine model. The transferred,expanded natural killer cells proliferated in vivo in an interleukin-2 dose-dependent fashion,persisted up to 4 weeks,were readily detectable in the human bone,inhibited myeloma growth and protected bone from myeloma-induced osteolysis. CONCLUSIONS These studies provide the rationale for testing expanded natural killer cells in humans. View Publication

Human embryonic stem cell-derived dendritic cells (hESC-DCs) may potentially provide a platform to generate off-the-shelf" therapeutic cancer vaccines. To apply hESC-DCs for cancer immunotherapy in a semiallogeneic setting� View Publication

Lymphocyte activation gene-3 (LAG-3) is an inhibitory receptor expressed by CD4+ T cells and tempers their homeostatic expansion. Because CD4+ T cell proliferation is tightly coupled to bioenergetics,we investigate the role of LAG-3 in modulating naive CD4+ T cell metabolism. LAG-3 deficiency enhances the metabolic profile of naive CD4+ T cells by elevating levels of mitochondrial biogenesis. In vivo,LAG-3 blockade partially restores expansion and the metabolic phenotype of wild-type CD4+ T cells to levels of Lag3-/- CD4+ T cells,solidifying that LAG-3 controls these processes. Lag3-/- CD4+ T cells also demonstrate greater signal transducer and activator of transcription 5 (STAT5) activation,enabling resistance to interleukin-7 (IL-7) deprivation. These results implicate this pathway as a target of LAG-3-mediated inhibition. Additionally,enhancement of STAT5 activation,as a result of LAG-3 deficiency,contributes to greater activation potential in these cells. These results identify an additional mode of regulation elicited by LAG-3 in controlling CD4+ T cell responses. View Publication

The hexamethylene bisacetamide (HMBA) anticancer drug was dismissed due to limited efficacy in leukemic patients but it may re-enter into the clinics in HIV-1 eradication strategies because of its recently disclosed capacity to reactivate latent virus. Here,we investigated the impact of HMBA on the cytotoxicity of natural killer (NK) cells against acute T lymphoblastic leukemia (T-ALL) cells or HIV-1-infected T cells that exit from latency. We show that in T-ALL cells HMBA upmodulated MICB and ULBP2 ligands for the NKG2D activating receptor. In a primary CD4+ T cell-based latency model,HMBA did not reactivate HIV-1,yet enhanced ULBP2 expression on cells harboring virus reactivated by prostratin (PRO). However,HMBA reduced the expression of NKG2D and its DAP10 adaptor in NK cells,hence impairing NKG2D-mediated cytotoxicity and DAP10-dependent response to IL-15 stimulation. Alongside,HMBA dampened killing of T-ALL targets by IL-15-activated NK cells and impaired NK cell-mediated clearance of PRO-reactivated HIV-1+ cells. Overall,our results demonstrate a dominant detrimental effect of HMBA on the NKG2D pathway that crucially controls NK cell-mediated killing of tumors and virus-infected cells,providing one possible explanation for poor clinical outcome in HMBA-treated cancer patients and raising concerns for future therapeutic application of this drug. View Publication

In the inner ear,endolymph fluid surrounds the organ of Corti,which is important for auditory function; notably,even slight environmental changes mediated by trauma or infection can have significant consequences. However,it is unclear how the immune response is modulated in these tissues. Here,we report the local immune surveillance role of cleaved cochlin LCCL (Limulus factor C,Cochlin,and Lgl1) during Pseudomonas aeruginosa infection in the cochlea. Upon infection,the LCCL domain is cleaved from cochlin and secreted into the perilymph. This cleaved fragment sequesters infiltrating bacteria in the scala tympani and subsequently recruits resident immune cells to eliminate the bacteria. Importantly,hearing loss in a cochlin knockout mouse model is remedied by treatment with a cochlin LCCL peptide. These findings suggest cleaved cochlin LCCL constitutes a critical factor in innate immunity and auditory function and may be a potential therapeutic target to treat chronic otitis media-induced hearing loss. View Publication

Intestinal fibrosis is a serious complication in inflammatory bowel disease (IBD). Despite the remarkable success of recent anti-inflammatory therapies for IBD,incidence of intestinal fibrosis and need for bowel resection have not significantly changed. To clarify the contribution of haematopoietic-derived cells in intestinal fibrosis,we prepared bone marrow (BM) chimeric mice (chimeras),which were reconstituted with BM cells derived from enhanced green fluorescent protein (EGFP)-transgenic mice or CC chemokine receptor 2 (CCR2)-deficient mice. After 2 months of transplantation,BM chimeras were treated with azoxymethane/dextran sodium sulphate. During chronic inflammation,CCR2+ BM-derived monocyte and fibrocyte infiltration into the colon and CC chemokine ligand 2 production increased,leading to colon fibrosis in EGFP BM chimeras. In CCR2-deficient BM chimeras,monocyte and fibrocyte numbers in the colonic lamina propria significantly decreased,and colon fibrosis was attenuated. In colon tissue,mRNA expression of tissue inhibitor of metalloproteinase (TIMP)-1 but not of collagen I,transforming growth factor-beta1 or matrix metalloproteinases was significantly different between the two chimeras. CCR2+ monocytes and fibrocytes showed high Timp1 mRNA expression. Our results suggest that infiltrating CCR2+ monocytes and their progenies,fibrocytes,promote colon fibrosis by inhibiting collagen degradation through TIMP-1 production. View Publication