The stages of human natural killer (NK) cell differentiation are not well established. Culturing CD34 ؉ progenitors with interleukin 7 (IL-7), IL-15, stem cell factor (SCF), FLT-3L, and murine fetal liver cell line (EL08.1D2), we identified 2 nonoverlapping subsets of differentiating CD56 ؉ cells based on CD117 and CD94 (CD117 high CD94 ؊ and CD117 low/؊ CD94 ؉ cells). Both populations expressed CD161 and NKp44, but differed with respect to NKp30, NKp46, NKG2A, NKG2C, NKG2D, CD8, CD16, and KIR. Only the CD117 low/؊ CD94 ؉ population displayed cytotoxicity and interferon-␥ production. Both populations arose from a single CD34 ؉ CD38 ؊ Lin ؊ cell and their percentages changed over time in a reciprocal fashion, with CD117 high CD94 ؊ cells predominating early and decreasing due to an increase of the CD117 low/؊ CD94 ؉ population. These 2 subsets represent distinct stages of NKcell differentiation, since purified CD117 high IntroductionNatural killer (NK) cells are CD56 ϩ CD3 Ϫ innate immune effector cells that recognize target cells that have undergone cellular stress, such as malignant transformation or viral infection. 1 Individual NK cells display a diverse repertoire of activating and inhibitory receptors, including the killer immunoglobulin-like receptors (KIRs), natural cytotoxicity receptors (NKp30, NKp44, and NKp46), and c-lectin receptors (NKG2A/ CD94, NKG2C/CD94, NKG2D, and CD161). The summation of activating signals, when not opposed by inhibitory signaling, leads to the release of granzymes and perforin and target cytolysis. 2 NK-cell activation also results in the elaboration of proinflammatory cytokines, including interferon ␥ (IFN-␥), 3,4 stimulating other compartments of the immune system.The stages of human NK-cell development are not well characterized. Since human NK cells can be differentiated from CD34 ϩ hematopoietic progenitor cells (HPCs) in vitro, such stages of differentiation may be elucidated. Early studies showed that interleukin 2 (IL-2) could induce the differentiation of NK cells from CD34 ϩ HPCs. 5,6 More recently, IL-15 has been found to be critical for NK-cell development since IL-15 Ϫ/Ϫ and IL-15R␣ Ϫ/Ϫ mice show a near-complete absence of NK cells. 7,8 Accordingly, culture of human HPCs with IL-15 gives rise to NK cells, 9 but other cytokines, such as IL-3, IL-7, stem cell factor (SCF), and FLT-3L increase the efficiency of in vitro NK-cell differentiation. [10][11][12] Both SCF and FLT-3L induce the expression of IL-15R␣ mRNA in developing progenitors, inducing IL-15 responsiveness. 11 CD34 ϩ cells cultured with cytokines and stromal cells give higher yields of NK cells that more accurately reflect peripheral blood NK cells with respect to KIR expression. [12][13][14][15] To prevent auto-aggression, NK cells express inhibitory receptors that recognize self major histocompatibility complex (MHC) class I. The current paradigm of NK-cell tolerance suggests that every NK cell must express at least one self MHC-specific inhibitory receptor, since this has been demonstrated at both t...

IMPORTANCE High placebo responses have been observed across a wide range of pathologies, severely impacting drug development.OBJECTIVE To examine neurochemical mechanisms underlying the formation of placebo effects in patients with major depressive disorder (MDD). DESIGN, SETTING, AND PARTICIPANTSIn this study involving 2 placebo lead-in phases followed by an open antidepressant administration, we performed a single-blinded 2-week crossover randomized clinical trial of 2 identical oral placebos (described as having either active or inactive fast-acting antidepressant-like effects) followed by a 10-week open-label treatment with a selective serotonin reuptake inhibitor or, in some cases, another agent as clinically indicated. The volunteers (35 medication-free patients with MDD at a university health system) were studied with positron emission tomography and the μ-opioid receptor-selective radiotracer [ 11 C]carfentanil after each 1-week inactive and active oral placebo treatment. In addition, 1 mL of isotonic saline was administered intravenously within sight of the volunteer during positron emission tomographic scanning every 4 minutes over 20 minutes only after the 1-week active placebo treatment, with instructions that the compound may be associated with the activation of brain systems involved in mood improvement. This challenge stimulus was used to test the individual capacity to acutely activate endogenous opioid neurotransmision under expectations of antidepressant effect. MAIN OUTCOMES AND MEASURESChanges in depressive symptoms in response to active placebo and antidepressant. Baseline and activation measures of μ-opioid receptor binding. RESULTSHigher baseline μ-opioid receptor binding in the nucleus accumbens was associated with better response to antidepressant treatment (r = 0.48; P = .02). Reductions in depressive symptoms after 1 week of active placebo treatment, compared with the inactive, were associated with increased placebo-induced μ-opioid neurotransmission in a network of regions implicated in emotion, stress regulation, and the pathophysiology of MDD, namely, the subgenual anterior cingulate cortex, nucleus accumbens, midline thalamus, and amygdala (nucleus accumbens: r = 0.6; P < .001). Placebo-induced endogenous opioid release in these regions was associated with better antidepressant treatment response, predicting 43% of the variance in symptom improvement at the end of the antidepressant trial.CONCLUSIONS AND RELEVANCE These data demonstrate that placebo-induced activation of the μ-opioid system is implicated in the formation of placebo antidepressant effects in patients with MDD and also participate in antidepressant responses, conferring illness resiliency, during open administration.TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT02178696

Background Recent neuroimaging studies have demonstrated resting-state functional connectivity (rsFC) abnormalities among intrinsic brain networks in Major Depressive Disorder (MDD); however, their role as predictors of treatment response has not yet been explored. Here, we investigate whether network-based rsFC predicts antidepressant and placebo effects in MDD. Methods We performed a randomized controlled trial of two weeklong, identical placebos (described as having either “active” fast-acting, antidepressant effects or as “inactive”) followed by a ten-week open-label antidepressant medication treatment. Twenty-nine participants underwent a rsFC fMRI scan at the completion of each placebo condition. Networks were isolated from resting-state blood-oxygen-level-dependent signal fluctuations using independent component analysis. Baseline and placebo-induced changes in rsFC within the default-mode, salience, and executive networks were examined for associations with placebo and antidepressant treatment response. Results Increased baseline rsFC in the rostral anterior cingulate (rACC) within the salience network, a region classically implicated in the formation of placebo analgesia and the prediction of treatment response in MDD, was associated with greater response to one week of active placebo and ten weeks of antidepressant treatment. Machine learning further demonstrated that increased salience network rsFC, mainly within the rACC, significantly predicts individual responses to placebo administration. Conclusions These data demonstrate that baseline rsFC within the salience network is linked to clinical placebo responses. This information could be employed to identify patients who would benefit from lower doses of antidepressant medication or non-pharmacological approaches, or to develop biomarkers of placebo effects in clinical trials.

Uremic pruritus is one of the most bothersome symptoms in patients with chronic renal failure. Its pathogenesis remains unclear. The aim of this study was to evaluate the frequency of uremic pruritus in hemodialysis patients and to correlate its presence and intensity with several clinical parameters. One hundred thirty patients on maintenance hemodialysis were included into the study. The intensity of pruritus was assessed by two methods: visual analog scale and specially adapted questionnaire scoring method. A significantly positive correlation (p < 0.00001) was demonstrated between the two methods for evaluating pruritus. Uremic pruritus was found in 40.8% of patients. An additional 36.1% of patients reported pruritus to have been present in the past during the renal disease period. Itching was generalized in 19% of patients; the remaining subjects suffered from scattered pruritus (50%) or pruritus in a single location (31%). A significant positive relationship (p < 0.02) was demonstrated between the total score of pruritus and duration of the hemodialysis period. Severity of pruritus and sleep disturbance caused by itching also significantly correlated (p < 0.05) with the duration of hemodialysis. Patients hemodialysed on polysulphone membranes more commonly suffered from pruritus than those on hemophane (p < 0.04) or cuprophane (p < 0.03) dialysis membranes. A marked relationship was demonstrated between the intensity of xerosis and prevalence of pruritus. Significantly more patients with very rough skin had pruritus compared to those with rough skin (p < 0.05) and those with slightly dry skin (p < 0.02). Itching was more common in female patients (p < 0.04), but patient age, underlying renal disease and erythropoietin intake did not correlate with the incidence or intensity of pruritus.

Background Recent meta-analyses of resting-state networks in major depressive disorder (MDD) implicate network disruptions underlying cognitive and affective features of illness. Heterogeneity of findings to date may stem from the relative lack of data parsing clinical features of MDD such as phase of illness and the burden of multiple episodes. Method Resting-state functional magnetic resonance imaging data were collected from 17 active MDD and 34 remitted MDD patients, and 26 healthy controls (HCs) across two sites. Participants were medication-free and further subdivided into those with single v. multiple episodes to examine disease burden. Seed-based connectivity using the posterior cingulate cortex (PCC) seed to probe the default mode network as well as the amygdala and subgenual anterior cingulate cortex (sgACC) seeds to probe the salience network (SN) were conducted. Results Young adults with remitted MDD demonstrated hyperconnectivity of the left PCC to the left inferior frontal gyrus and of the left sgACC to the right ventromedial prefrontal cortex (PFC) and left hippocampus compared with HCs. Episode-independent effects were observed between the left PCC and the right dorsolateral PFC, as well as between the left amygdala and right insula and caudate, whereas the burden of multiple episodes was associated with hypoconnectivity of the left PCC to multiple cognitive control regions as well as hypoconnectivity of the amygdala to large portions of the SN. Conclusions This is the first study of a homogeneous sample of unmedicated young adults with a history of adolescent-onset MDD illustrating brain-based episodic features of illness.

Dopamine (DA) neurotransmission within the brain’s reward circuit has been implicated in the pathophysiology of depression and in both, cognitive and pharmacological mechanisms of treatment response. Still, a direct relationship between measures of DA neurotransmission and reward-related deficits in patients with depression has not been demonstrated. To gain insight into the symptom-specific alterations in the DA system in patients with depression, we used positron emission tomography (PET) and the D2/3 receptor-selective radiotracer [11C]raclopride in twenty-three non-smoking un-medicated Major Depressive Disorder (MDD) patients and sixteen healthy controls (HC). We investigated the relationship between D2/3 receptor availability and baseline measures of depression severity, anxiety, anhedonia, and cognitive and pharmacological mechanisms of treatment response. We found that, compared to controls, patients with depression showed greater D2/3 receptor availability in several striatal regions, including the bilateral ventral pallidum/nucleus accumbens (vPAL/NAc), and the right ventral caudate and putamen. In the depressed sample, D2/3 receptor availability in the caudal portion of the ventral striatum (NAc/vPAL) correlated with higher anxiety symptoms, whereas D2/3 receptor availability in the rostral area of the ventral striatum correlated negatively with the severity of motivational anhedonia. Finally, MDD non-remitters showed greater baseline anxiety, greater D2/3 availability in the NAc/vPAL, and greater placebo-induced DA release in the bilateral NAc. Our results demonstrate abnormally high D2/3 receptor availability in the ventral striatum of patients with MDD, which seem to be associated with comorbid anxiety symptoms and lack of response to antidepressants.

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The molecular alterations that underlie the long-lasting behavioural effects of drugs of abuse, such as psychomotor sensitization and physical dependence, are still not known. Moreover, it is not known which molecular effects are similar for addictive drugs from various pharmacological classes. In this study, we utilized wholegenome microarray profiling to evaluate the detailed time-course of transcriptional alterations in the mouse striatum during chronic treatment with heroin (HER) and methamphetamine (METH) and after period of spontaneous withdrawal. We identified 27 genes regulated by chronic drug administration. The overlap between lists of HER-and METH-induced genes was highly significant. The most substantial impact on the gene expression profile was observed for circadian genes (Per1, Per2 and Nr1d1). However, changing the treatment scheme from diurnal to nocturnal was sufficient to attenuate the drug-induced changes in circadian gene mRNA levels. Both of the drugs caused a dose-dependent induction in glucocorticoid-dependent genes with relatively long mRNA half-lives (Fkbp5, Sult1a1 and Plin4). The analysis also showed a drug-regulated group of transcripts enriched in the nucleus accumbens and includes well known (Pdyn, Cartpt and Rgs2) as well as new (Fam40b and Inmt) candidate genes. All identified alterations in the striatal transcriptome were transient and persisted up to 6 days after withdrawal. Behavioural sensitization, however, was maintained throughout the 12-day withdrawal period for both HER and METH. We suggest that transient gene expression alterations during drug treatment and in the early period of withdrawal are involved in the establishment of persistent neuroplastic alterations responsible for the development of drug addiction.