Donor-recipient ethnic mismatching impacts short- and long-term results of heart transplantation.

BACKGROUND: The impact of donor-recipient ethnic matching on heart transplantation (HT) has been poorly studied with inconclusive results. We aimed to investigate the impact of ethnic matching on HT outcomes in Israeli multiethnic patients. METHODS: The study comprised 168 patients who underwent HT from 1990-2017. Patients and their donors were ethnically categorized to Jews and Arabs. Primary end points were all-cause in-hospital and late mortality; secondary end points included primary graft dysfunction (PGD), rejections, and vasculopathy. RESULTS: Donor-recipient ethnic matching was found in 111 patients, while 57 were ethnically mismatched. Baseline characteristics were similar in both groups. Ethnic mismatching was associated with >7-fold (P = 0.018) increased risk for in-hospital mortality and >8-fold (P < 0.001) increased risk for PGD. Kaplan-Meier survival analysis showed that overall survival at 10 years was significantly higher among matched patients (73% vs 43%, log-rank P < 0.001). Multivariate analysis showed that ethnic mismatching was associated with an approximately fourfold higher risk for death (P < 0.01). These findings were validated by propensity score analysis. The ethnic mismatched group experienced significantly higher rejection rates compared with the matched group with lower survival free of rejections (log-rank P = 0.029). No differences in vasculopathy were found. CONCLUSIONS: Donor-recipient ethnic mismatch is an important independent predictor of early- and long-term outcomes following HT, and is associated with increased risk for PGD, rejections, and mortality. These findings will help to design tailored treatment protocols leading to improved outcomes after HT.

Individual olfactory perception reveals meaningful nonolfactory genetic information.

Each person expresses a potentially unique subset of ∼ 400 different olfactory receptor subtypes. Given that the receptors we express partially determine the odors we smell, it follows that each person may have a unique nose; to capture this, we devised a sensitive test of olfactory perception we termed the "olfactory fingerprint." Olfactory fingerprints relied on matrices of perceived odorant similarity derived from descriptors applied to the odorants. We initially fingerprinted 89 individuals using 28 odors and 54 descriptors. We found that each person had a unique olfactory fingerprint (P < 10(-10)), which was odor specific but descriptor independent. We could identify individuals from this pool using randomly selected sets of 7 odors and 11 descriptors alone. Extrapolating from this data, we determined that using 34 odors and 35 descriptors we could individually identify each of the 7 billion people on earth. Olfactory perception, however, fluctuates over time, calling into question our proposed perceptual readout of presumably stable genetic makeup. To test whether fingerprints remain informative despite this temporal fluctuation, building on the linkage between olfactory receptors and HLA, we hypothesized that olfactory perception may relate to HLA. We obtained olfactory fingerprints and HLA typing for 130 individuals, and found that olfactory fingerprint matching using only four odorants was significantly related to HLA matching (P < 10(-4)), such that olfactory fingerprints can save 32% of HLA tests in a population screen (P < 10(-6)). In conclusion, a precise measure of olfactory perception reveals meaningful nonolfactory genetic information.

Central nervous system acute lymphoblastic leukemia: role of natural killer cells.

Central nervous system acute lymphoblastic leukemia (CNS-ALL) is a major clinical problem. Prophylactic therapy is neurotoxic, and a third of the relapses involve the CNS. Increased expression of interleukin 15 (IL-15) in leukemic blasts is associated with increased risk for CNS-ALL. Using in vivo models for CNS leukemia caused by mouse T-ALL and human xenografts of ALL cells, we demonstrate that expression of IL-15 in leukemic cells is associated with the activation of natural killer (NK) cells. This activation limits the outgrowth of leukemic cells in the periphery, but less in the CNS because NK cells are excluded from the CNS. Depletion of NK cells in NOD/SCID mice enabled combined systemic and CNS leukemia of human pre-B-ALL. The killing of human leukemia lymphoblasts by NK cells depended on the expression of the NKG2D receptor. Analysis of bone marrow (BM) diagnostic samples derived from children with subsequent CNS-ALL revealed a significantly high expression of the NKG2D and NKp44 receptors. We suggest that the CNS may be an immunologic sanctuary protected from NK-cell activity. CNS prophylactic therapy may thus be needed with emerging NK cell-based therapies against hematopoietic malignancies.

The Impact of the Donor Card Holder Prioritization Program on Kidney Allocation in Israel.

BACKGROUND: Since 2014, as part of a priority program within the Israeli Transplant Law, additional points were given to waitlisted candidates with donor cards. We assessed the impact on deceased donor kidney allocation. METHODS: This study enrolled all patients older than 18 y who underwent deceased donor kidney transplantation (January 2016-December 2019). Data were obtained from the National HLA Tissue Laboratory registry at the Sheba Medical Center. Patients were grouped by donor card status (ADI group) (not signed, 0 points; relative signed, 0.1 points; patient signed, 2 points; and relative donated, 9 points). The primary outcome was waiting time until kidney transplantation with and without the additional score. RESULTS: Four hundred forty-four patients underwent kidney transplantation during the study period: 281 (63%) were donor card holders (DCH) and 163 (37%) were not DCH. DCH with extra points waited 68.0 (±47.0) mo on average, compared with 94.6 (±47.3) mo for not DCH ( P  < 0.001). Donor card signers had a shorter time until transplant in a multivariable model. Without extra points, 145 recipients (32.6%) would have missed organs allocated to higher-scored candidates. Allocation changes occurred in 1 patient because of an additional 0.1 points, in 103 candidates because of an additional 2 points, and in 41 candidates because of an additional 9 points. CONCLUSIONS: Additional DCH scores improved allocation and reduced waiting time for donor card signers and those with donating relatives. To enhance fairness, consideration should be given to reducing the score weight of this social criterion and raising scores for other factors, especially dialysis duration.

Compound heterozygosity of HLA-DRB3*01:01 and HLA-DRB4*01:01 as a potential predictor of fetal neonatal alloimmune thrombocytopenia.

BACKGROUND: Fetal neonatal alloimmune thrombocytopenia (FNAIT) is a life-threatening bleeding disorder in the fetus or neonate caused by maternal alloantibodies directed against fetal platelet (PLT) antigens inherited from the father. The immune-dominant antigen leading to severe FNAIT is the human PLT antigen (HPA)-1, whose polymorphism constitutes an epitope for human leukocyte antigens (HLAs), usually DRB3*0101 leading to an immune response. STUDY DESIGN AND METHODS: In this study our aims were to find whether other allele variants of the ß subunit of the HLA-DR family specifically focused on the HLA residues that bind Position 33 of the HPA-1 integrin contribute to FNAIT development and affect response to treatment and whether coexistence of both anti-HPA-1a and anti-HLA class I specific against the father's antigens leads to a more severe thrombocytopenia in the newborn. We examine the genotype of 23 mothers to newborns with FNAIT compared to a control group. RESULTS: Our results suggested that, when HPA-1 incompatibility with the husband is found, the presence of two HLA alleles (DRB3*01:01 and DRB4*01:01) in the mother increases the risk and severity of FNAIT and reduces the success of a preventive immunoglobulin G treatment. We provide a structural model for the molecular basis of the rational effects of the different HLA alleles. In addition, we found that the presence of both anti-HPA-1 and anti-HLAs did not aggravate FNAIT in comparison to mothers harboring only anti-HPA-1. CONCLUSION: Overall, we suggest that a specific genotyping of the mother in relation to HLA-DRB as well as HPA-1 can serve as an antenatal diagnostic tool, particularly in siblings of women who gave birth to neonates with FNAIT.

Differences in Telomere Length between Adolescent Females with Anorexia Nervosa Restricting Type and Anorexia Nervosa Binge-Purge Type.

Physiological and psychological distress may accelerate cellular aging, manifested by shortening of telomere length (TL). The present study focused on TL shortening in anorexia nervosa (AN), an illness combining physiological and psychological distress. For that purpose, we measured TL in 44 female adolescents with AN at admission to inpatient treatment, in a subset of 18 patients also at discharge, and in 22 controls. No differences in TL were found between patients with AN and controls. At admission, patients with AN-binge/purge type (AN-B/P; n = 18) showed shorter TL compared with patients with AN-restricting type (AN-R; n = 26). No change in TL was found from admission to discharge, despite an improvement in body mass index standard deviation score (BMI-SDS) following inpatient treatment. Older age was the only parameter assessed to be correlated with greater TL shortening. Several methodological changes have to be undertaken to better understand the putative association of shorter TL with B/P behaviors, including increasing the sample size and the assessment of the relevant pathological eating disorder (ED) and non-ED psychological correlates in the two AN subtypes.

New Insights on DR and DQ Human Leukocyte Antigens in Anti-LGI1 Encephalitis.

BACKGROUND AND OBJECTIVES: To explore the clinical characteristics and HLA associations of patients with anti-leucine-rich glioma-inactivated 1 encephalitis (LGI1E) from a large single center in Israel. Anti-LGI1E is the most commonly diagnosed antibody-associated encephalitic syndrome in adults. Recent studies of various populations reveal significant associations with specific HLA genes. We examined the clinical characteristics and HLA associations of a cohort of Israeli patients. METHODS: Seventeen consecutive patients with anti-LGI1E diagnosed at Tel Aviv Medical Center between the years 2011 and 2018 were included. HLA typing was performed using next-generation sequencing at the tissue typing laboratory of Sheba Medical Center and compared with data from the Ezer Mizion Bone Marrow Donor Registry, containing over 1,000,000 samples. RESULTS: Our cohort displayed a male predominance and median age at onset in the 7th decade, as previously reported. The most common presenting symptom was seizures. Notably, paroxysmal dizziness spells were significantly more common than previously reported (35%), whereas faciobrachial dystonic seizures were found only in 23%. HLA analysis revealed overrepresentation of DRB1*07:01 (OR: 3.18, CI: 20.9 p < 1.e-5) and DRB1*04:02 (OR: 3.8, CI: 20.1 p < 1.e-5), as well as of the DQ allele DQB1*02:02 (OR: 2.8, CI: 14.2 p < 0.0001) as previously reported. A novel overrepresentation observed among our patients was of the DQB1*03:02 allele (OR: 2.3, CI: 6.9 p < 0.008). In addition, we found DR-DQ associations, among patients with anti-LGI1E, that showed complete or near-complete linkage disequilibrium (LD). By applying LD analysis to an unprecedentedly large control cohort, we were able to show that although in the general population, DQB*03:02 is not fully associated with DRB1*04:02, in the patient population, both alleles are always coupled, suggesting the DRB1*04:02 association to be primary to disease predisposition. In silico predictions performed for the overrepresented DQ alleles reveal them to be strong binders of LGI1-derived peptides, similarly to overrepresented DR alleles. These predictions suggest a possible correlation between peptide binding sites of paired DR-DQ alleles. DISCUSSION: Our cohort presents distinct immune characteristics with substantially higher overrepresentation of DRB1*04:02 and slightly lower overrepresentation of DQB1*07:01 compared with previous reports implying differences between different populations. DQ-DR interactions found in our cohort may shed additional light on the complex role of immunogenetics in the pathogenesis of anti-LGI1E, implying a possible relevance of certain DQ alleles and DR-DQ interactions.

Clone clusters in autoreactive CD4 T-cell lines from probable multiple sclerosis patients form disease-characteristic signatures.

We developed a method for selectively propagating disease-related autoreactive T-cell lines (auTCLs) based on their increased resistance to apoptosis. The generated auTCLs homogeneously co-express CD45RO and CD49a, adhere strongly to extracellular matrix proteins and express high interleukin-17 (IL-17) messenger RNA levels, resembling a T-cell subset proposed to transmigrate into tissues and induce systemic and local inflammation in rheumatoid arthritis. The combinations of T-cell oligoclones that comprise probable multiple sclerosis (pMS) disease-related lines use a unique portfolio of T-cell receptor beta-chain variable allele (BV genes) combinations forming 'disease-specific cluster patterns'. The auTCL derived from different patients and from different myelin epitopes display striking similarities in BV gene allele clusters and are derived primarily from a disease-prone hotspot residing in the BV gene locus between Vbeta6 and Vbeta9. Conversely, healthy subject TCLs use different BV gene allele sets, forming 'healthy responder usage formats'. These formats were absent from the pMS patient V-beta gene allele combinations evaluated in this study. Hierarchical clustering of the BV gene combinations, distinguish three pMS auTCL groups, implying existence of up to three disease-related immune response patterns. These subgroup patterns may reflect different disease subclasses or alternatively they may suggest immune reactivity to different aetiological agents. Analyses of clonal-clustering patterns may potentially aid in subclassification of MS or in characterizing aetiological agents of this disease.

Donor-derived brain tumor following neural stem cell transplantation in an ataxia telangiectasia patient.

BACKGROUND: Neural stem cells are currently being investigated as potential therapies for neurodegenerative diseases, stroke, and trauma. However, concerns have been raised over the safety of this experimental therapeutic approach, including, for example, whether there is the potential for tumors to develop from transplanted stem cells. METHODS AND FINDINGS: A boy with ataxia telangiectasia (AT) was treated with intracerebellar and intrathecal injection of human fetal neural stem cells. Four years after the first treatment he was diagnosed with a multifocal brain tumor. The biopsied tumor was diagnosed as a glioneuronal neoplasm. We compared the tumor cells and the patient's peripheral blood cells by fluorescent in situ hybridization using X and Y chromosome probes, by PCR for the amelogenin gene X- and Y-specific alleles, by MassArray for the ATM patient specific mutation and for several SNPs, by PCR for polymorphic microsatellites, and by human leukocyte antigen (HLA) typing. Molecular and cytogenetic studies showed that the tumor was of nonhost origin suggesting it was derived from the transplanted neural stem cells. Microsatellite and HLA analysis demonstrated that the tumor is derived from at least two donors. CONCLUSIONS: This is the first report of a human brain tumor complicating neural stem cell therapy. The findings here suggest that neuronal stem/progenitor cells may be involved in gliomagenesis and provide the first example of a donor-derived brain tumor. Further work is urgently needed to assess the safety of these therapies.

Ethnic disparity in Israel impacts long-term results after heart transplantation.

BACKGROUND: Ethnicity may affect graft longevity and recipient mortality after heart transplantation (HTx). We hypothesized that differences in ethnic origin between Arabs and Jews undergoing HTx in Israel may contribute to differences in long-term outcomes. METHODS: The study population comprised all 254 patients who underwent HTx between 1991 and 2017 in a tertiary medical center located in the center of Israel. Patients were categorized as either Jews (226 patients, 89%) or Arabs (28 patients, 11%). The primary end point was cardiac allograft vasculopathy (CAV), secondary end points were cardiovascular (CV) mortality and the combined end point of CAV/CV mortality. RESULTS: In comparison with Jews, Arab patients were significantly younger (ave. age 42 vs. 50) and had shorter in-hospital stay (45 vs. 80 days). However, Kaplan-Meier survival analysis showed that at 10 years of follow-up CAV rates were significantly higher among Arabs (58%) compared with Jews (23%; log-rank P = 0.01) for the overall difference during follow-up. Similar results were shown for the separate end point of CV mortality and the combined end point of CAV/CV mortality. Multivariate analysis, which controlled for age, gender, statin treatment, and other potential confounders, showed that Arab recipient ethnic origin was associated with a significant > 2.5-fold (p = 0.01) increase in the risk for CAV; a > 4-fold increase in the risk for CV mortality (p = 0.001); and approximately 4-fold increase in the risk for the combined end point (p = 0.001). These findings were validated by propensity score analysis. CONCLUSIONS: Our data suggest that Arab ethnic origin is associated with a significantly increased risk for CAV and mortality following HTx. Suggested explanations contributing to ethnic disparities in Israel include socioeconomic, environmental and genetic factors. Further studies are required to evaluate whether more aggressive risk factor management in the Israeli Arab population following HTx would reduce CAV and CV mortality in this high-risk population. Increased awareness and early intervention of the Israeli healthcare system and cooperation with the Arab community is of paramount importance.

A new MALDI-TOF-based assay for monitoring JAK2 V617F mutation level in patients undergoing allogeneic stem cell transplantation (allo SCT) for classic myeloproliferative disorders (MPD).

JAK2 V617F mutation is found in a high proportion of MPD patients. We developed a quantitative assay for the detection of the JAK2 mutation and demonstrated its clinical utility in MPD patients who underwent SCT. Sixty percent of the patients were JAK2 V617F positive prior to the SCT (mean mutation levels 74%, range 16-98%). After the procedure, the mutation levels progressively decreased and were in correlation with the donor-recipient chimerism status (r=0.97, p<0.001). At a median follow up of 16 months (range 2-58), 9/15 patients are alive and in CR. The levels of the JAK2 V617F mutation reached 0% in all surviving patients.

Modulation of adiponectin and leptin during refeeding of female anorexia nervosa patients.

CONTEXT: Several studies assessed adiponectin levels in anorexia nervosa (AN) patients, however, data regarding the dynamics of changes in adiponectin levels during refeeding of these patients is limited and contradicting. OBJECTIVE: Our objective was to assess adiponectin levels and the distribution of its different isoforms in AN patients before and after long-term refeeding, and to relate them to alterations in body mass index, leptin, insulin sensitivity, and additional endocrine parameters. DESIGN, SETTING, AND PARTICIPANTS: We conducted a longitudinal controlled study of 38 female adolescent malnourished AN inpatients, with 13 young, lean, healthy women serving as controls. Blood samples were obtained upon admission and thereafter at 1, 3, and 5 months (at target weight). MAIN OUTCOME MEASURES: Changes in body mass index, leptin, adiponectin, insulin sensitivity, and adiponectin multimeric forms were measured. RESULTS: At admission, leptin levels of AN patients were significantly lower, whereas insulin sensitivity (assessed by homeostasis model assessment-insulin resistance), adiponectin levels, and the ratio of high molecular weight (HMW) adiponectin to total adiponectin were significantly higher compared with controls. During weight recovery, leptin levels and homeostasis model assessment-insulin resistance increased significantly, whereas adiponectin and HMW adiponectin/total adiponectin ratio decreased significantly, to levels similar to controls. An initial increase in adiponectin levels was observed after 1 month of refeeding. There was no correlation between adiponectin and either T(4) or cortisol levels. CONCLUSIONS: Our study demonstrates hyperadiponectinemia, increased adiponectin HMW isoform, and increased insulin sensitivity in adolescent AN female patients and reversal of these findings with weight rehabilitation. We hypothesize that increased adiponectin levels may have a protective role in maintaining energy homeostasis during extreme malnourishment.

HLA-G expression is induced in Epstein-Barr virus-transformed B-cell lines by culture conditions.

Human leukocyte antigen-G (HLA-G) belongs to the nonclassical HLA class I family of genes presently designated as class Ib genes. It was found to be expressed mainly in placental tissue and in the thymus. Expression of HLA-G is induced by lymphokines such as interleukin-10 and has been associated with the escape of tumor cells from immune surveillance or with inhibition of graft rejection. In this report, Epstein-Barr virus-transformed B-cell lines established from peripheral blood lymphocytes from healthy volunteers were studied. Our results show that EBV-transformed B-cell lines, but not freshly separated peripheral blood lymphocytes, can be induced to express HLA-G either by subjecting the cultures to nutrient deficiency to hypoxia or to both, however, not all cell lines responded equally to stress conditions. The association of HLA-G with certain cancer transformations may suggest that the resistance to HLA-G expression could be related to susceptibility to the development of malignancy.

The immunogenetics of pemphigus vulgaris.

Pemphigus vulgaris (PV) is an autoimmune blistering disease of the skin of unknown etiology. While various environmental factors have been implicated as triggering agents, HLA association is probably the most important predisposing factor. The aim of this review is to highlight the association of HLA with pemphigus vulgaris. In addition, we present recent results showing a possible association with the nonclassical HLA-G antigen.

Pemphigus vulgaris is associated with the transporter associated with antigen processing (TAP) system.

Pemphigus vulgaris (PV) is a human leukocute antigen (HLA) class II-associated autoimmune disease of the skin of unknown etiology. We recently described the association of pemphigus vulgaris with two clusters of microsatellite loci within the major histocompatibility complex region. One cluster includes the microsatellite marker TAP1CA, located in proximity to the transporter associated with antigen processing (TAP) genes. These genes are essential for class I antigen processing machinery and could be an additional set of genes involved in susceptibility to PV. The aim of this study was to investigate a possible association between TAP gene polymorphisms and PV. For this purpose we examined 37 unrelated Jewish Israeli patients with PV and compared them with 37 healthy Israeli Jewish HLA-matched controls. Significant differences were detected in TAP2 amino acid residues (p=0.001). Two PV TAP2 risk alleles were identified (TAP2*C and TAP2*D), the frequency of which was estimated to be 37.8% in the patients and 5.3 % in the controls. This association was found to be independent of HLA-DR. It is therefore likely that TAP2 genes are involved in susceptibility to development of PV.

HLA-G is associated with pemphigus vulgaris in Jewish patients.

Pemphigus is a group of life-threatening autoimmune blistering diseases of the skin and mucous membranes. The etiology and pathogenesis of this destructive autoimmune process remains unknown, but significant association with human leukocyte antigen (HLA) factors have been described in pemphigus vulgaris (PV) patient cohorts worldwide. We have recently analyzed DNA samples obtained from pemphigus patients and matched controls with a set of microsatellite markers, and found that markers mapped to HLA class I region are significantly associated with the disease. In order to narrow the region that is associated with the disease single nucleotide polymorphism (SNP) technology was used. In this study, a set of 26 SNP markers, which span a chromosomal region of about 600,000 bp, were used to screen DNA samples of the patients and their matched controls. Of the 26 SNPs, four markers were found informative, all mapped to HLA-G. Typing patients and controls for HLA-G polymorphism revealed significant differences in the exon 8 deletion/insertion variant. The latter is probably associated with the efficiency of transcription of this gene. Taken together, the results suggest that HLA-G is associated with PV in Jewish patients.

Pemphigus vulgaris in Jewish patients is associated with HLA-A region genes: mapping by microsatellite markers.

Pemphigus vulgaris (PV) is the most severe autoimmune blistering disorder of the skin that is mediated by circulating autoantibodies against desmoglein 3 (Dsg3). It has been reported that in Jews the associated haplotype in PV is human leukocyte antigen (HLA) B38, DRB1*0402, DQB1*0302. Significant associations with HLA were observed also in non-Jews. Dsg3-specific T-cell responses were detected in PV patients but also in healthy individuals who were either carriers of the PV-associated DRB1*0402 allele or alleles that share similar or identical peptide binding motifs to DRB1*0402. This suggests that genes other than the classical major histocompatibility complex (MHC) genes are associated with the development of the autoimmune response. We used 16 microsatellite probes that span the entire MHC region to screen DNA samples from 38 PV patients and 76 healthy controls. Results demonstrated that some markers were associated with class II region including a TAP associated marker. However, four probes, D6S265, C_527, D6S510, and MOGC, which are all mapped to the region of HLA-A, were highly associated with PV. These results suggest that a gene, or genes in the class I region are important in the initiation of the autoimmune cascade. Activation/suppression of these genes might act as the trigger mechanism that starts the autoimmune destructive process.

Differences in number and activity of peripheral natural killer cells in primary versus secondary recurrent miscarriage.

OBJECTIVE: To compare peripheral natural-killer (NK) cell numbers and activity in women with primary recurrent miscarriage, secondary recurrent miscarriage and controls. DESIGN: Observational study. Academic medical center. PATIENT(S): Thirty-eight women with primary recurrent miscarriage, 29 women with secondary recurrent miscarriage, and 25 control women. INTERVENTION(S): None.[1] The proportion of NK cells in the total lymphocyte population, [2] the concentration of NK cells per microliter of blood, and [3] NK activity (NKA), using both standard and whole-blood assays. RESULT(S): Primary aborters had the highest proportion and concentration of NK cells and had the highest activity using the standard assay. Secondary aborters had an intermediate level of these NK cell indices, whereas the control patients had the lowest levels. Using the whole-blood NKA assay, the differences between primary and secondary aborters were most apparent: primary aborters had significantly higher NKA than did either secondary aborters or control women (72, 40, and 35 lytic units, respectively). Approximately 50% of the variability in NKA could be attributed to differences in concentrations of NK cell per microliter of blood. CONCLUSION(S): The higher NKA evident in primary recurrent miscarriage and the reported higher efficacy of immunotherapy in primary aborters support the involvement of NK cells in the etiology of primary recurrent miscarriage.

Development of allogeneic NK cell adoptive transfer therapy in metastatic melanoma patients: in vitro preclinical optimization studies.

Natural killer (NK) cells have long been considered as potential agents for adoptive cell therapy for solid cancer patients. Until today most studies utilized autologous NK cells and yielded disappointing results. Here we analyze various modular strategies to employ allogeneic NK cells for adoptive cell transfer, including donor-recipient HLA-C mismatching, selective activation and induction of melanoma-recognizing lysis receptors, and co-administration of antibodies to elicit antibody-dependent cell cytotoxicity (ADCC). We show that NK cell activation and induction of the relevant lysis receptors, as well as co-administration of antibodies yield substantial anti-cancer effects, which are functionally superior to HLA-C mismatching. Combination of the various strategies yielded improved effects. In addition, we developed various clinically-compatible ex vivo expansion protocols that were optimized according to fold expansion, purity and expression of lysis receptors. The main advantages of employing allogeneic NK cells are accessibility, the ability to use a single donor for many patients, combination with various strategies associated with the mechanism of action, e.g. antibodies and specific activation, as well as donor selection according to HLA or CD16 genotypes. This study rationalizes a clinical trial that combines adoptive transfer of highly potent allogeneic NK cells and antibody therapy.

TMPRSS2/ERG promotes epithelial to mesenchymal transition through the ZEB1/ZEB2 axis in a prostate cancer model.

Prostate cancer is the most common non-dermatologic malignancy in men in the Western world. Recently, a frequent chromosomal aberration fusing androgen regulated TMPRSS2 promoter and the ERG gene (TMPRSS2/ERG) was discovered in prostate cancer. Several studies demonstrated cooperation between TMPRSS2/ERG and other defective pathways in cancer progression. However, the unveiling of more specific pathways in which TMPRSS2/ERG takes part, requires further investigation. Using immortalized prostate epithelial cells we were able to show that TMPRSS2/ERG over-expressing cells undergo an Epithelial to Mesenchymal Transition (EMT), manifested by acquisition of mesenchymal morphology and markers as well as migration and invasion capabilities. These findings were corroborated in vivo, where the control cells gave rise to discrete nodules while the TMPRSS2/ERG-expressing cells formed malignant tumors, which expressed EMT markers. To further investigate the general transcription scheme induced by TMPRSS2/ERG, cells were subjected to a microarray analysis that revealed a distinct EMT expression program, including up-regulation of the EMT facilitators, ZEB1 and ZEB2, and down-regulation of the epithelial marker CDH1(E-Cadherin). A chromatin immunoprecipitation assay revealed direct binding of TMPRSS2/ERG to the promoter of ZEB1 but not ZEB2. However, TMPRSS2/ERG was able to bind the promoters of the ZEB2 modulators, IL1R2 and SPINT1. This set of experiments further illuminates the mechanism by which the TMPRSS2/ERG fusion affects prostate cancer progression and might assist in targeting TMPRSS2/ERG and its downstream targets in future drug design efforts.