Altered metabolism in right basal ganglia associated with asymptomatic neurocognitive impairment in HIV-infected individuals.

Background: Only few studies have focused on the metabolite differences between asymptomatic neurocognitive impairment (ANI) and cognitively normal people living with HIV (PLWH). The current study aims to examine whether brain metabolisms in basal ganglia (BG) by magnetic resonance spectroscopy (MRS) were potential to discriminate ANI from cognitively normal PLWH. Methods: According to neuropsychological (NP) test, 80 PLWH (37.4 ± 10.2 years) were divided into ANI group (HIV-ANI, n = 31) and NP normal group (HIV-normal, n = 49). Brain metabolisms by MRS from right BG were compared between groups, including N-acetylaspartate and N-acetyl aspartylglutamate (tNAA), creatine and phosphocreatine (tCr), and choline-containing compounds (tCho). A total value of three metabolites were introduced. All brain metabolisms were evaluated as its percentage of total. Furthermore, correlations between MRS and NP and clinical measures were evaluated. A logistic regression model was applied, and the AUC values for the model and the continuous factors were compared using receiver operating curve (ROC) analysis. Results: Compared to HIV-normal group, tNAA/total was lower and tCr/total was higher in the HIV-ANI group (P < 0.05). Both tNAA/total and tCr/total values were correlated with NP score (P < 0.05), especially in verbal fluency, speed of information processing, learning, and recall (P < 0.05). The logistic model included BG-tCr/total, current CD4 and infection years of PLWH. The AUC value for the BG-tCr/total was 0.696 and was not significantly lower than that for logistic model (P < 0.01). Conclusion: The altered brain metabolites in the right BG were found in the ANI group compared to PLWH with normal cognition, and further associated with NP deficits. The current findings indicated that brain metabolites assessed by MRS has the potential to discriminate ANI from cognitively normal PLWH.

Morphological Changes of Frontal Areas in Male Individuals With HIV: A Deformation-Based Morphometry Analysis.

Objective: Previous studies on HIV-infected (HIV+) individuals have revealed brain structural alterations underlying HIV-associated neurocognitive disorders. Most studies have adopted the widely used voxel-based morphological analysis of T1-weighted images or tracked-based analysis of diffusion tensor images. In this study, we investigated the HIV-related morphological changes using the deformation-based morphometry (DBM) analysis of T1-weighted images, which is another useful tool with high regional sensitivity. Materials and Methods: A total of 157 HIV+ (34.7 ± 8.5 years old) and 110 age-matched HIV-uninfected (HIV-) (33.7 ± 10.1 years old) men were recruited. All participants underwent neurocognitive assessments and brain scans, including high-resolution structural imaging and resting-state functional imaging. Structural alterations in HIV+ individuals were analyzed using DBM. Functional brain networks connected to the deformed regions were further investigated in a seed-based connectivity analysis. The correlations between imaging and cognitive or clinical measures were examined. Results: The DBM analysis revealed decreased values (i.e., tissue atrophy) in the bilateral frontal regions in the HIV+ group, including bilateral superior frontal gyrus, left middle frontal gyrus, and their neighboring white matter tract, superior corona radiata. The functional connectivity between the right superior frontal gyrus and the right inferior temporal region was enhanced in the HIV+ group, the connectivity strength of which was significantly correlated with the global deficit scores (r = 0.214, P = 0.034), and deficits in learning (r = 0.246, P = 0.014) and recall (r = 0.218, P = 0.031). Increased DBM indexes (i.e., tissue enlargement) of the right cerebellum were also observed in the HIV+ group. Conclusion: The current study revealed both gray and white matter volume changes in frontal regions and cerebellum in HIV+ individuals using DBM, complementing previous voxel-based morphological studies. Structural alterations were not limited to the local regions but were accompanied by disrupted functional connectivity between them and other relevant regions. Disruptions in neural networks were associated with cognitive performance, which may be related to HIV-associated neurocognitive disorders.

The Resting State Central Auditory Network: a Potential Marker of HIV-Related Central Nervous System Alterations.

OBJECTIVE: HIV positive (HIV+) individuals with otherwise normal hearing ability show central auditory processing deficits as evidenced by worse performance in speech-in-noise perception compared with HIV negative (HIV-) controls. HIV infection and treatment are also associated with lower neurocognitive screening test scores, suggesting underlying central nervous system damage. To determine how central auditory processing deficits in HIV+ individuals relate to brain alterations in the cortex involved with auditory processing, we compared auditory network (AN) functional connectivity between HIV+ adults with or without speech-in-noise perception difficulties and age-matched HIV- controls using resting-state fMRI. DESIGN: Based on the speech recognition threshold of the hearing-in-noise test, twenty-seven HIV+ individuals were divided into a group with speech-in-noise perception abnormalities (HIV+SPabnl, 38.2 ± 6.8 years; 11 males and 2 females) and one without (HIV+SPnl 34.4 ± 8.8 years; 14 males). An HIV- group with normal speech-in-noise perception (HIV-, 31.3 ± 5.2 years; 9 males and 3 females) was also enrolled. All of these younger and middle-aged adults had normal peripheral hearing determined by audiometry. Participants were studied using resting-state fMRI. Independent component analysis was applied to identify the AN. Group differences in the AN were identified using statistical parametric mapping. RESULTS: Both HIV+ groups had increased functional connectivity (FC) in parts of the AN including the superior temporal gyrus, middle temporal gyrus, supramarginal gyrus, and Rolandic operculum compared to the HIV- group. Compared with the HIV+SPnl group, the HIV+SPabnl group showed greater FC in parts of the AN including the middle frontal and inferior frontal gyri. CONCLUSIONS: The classical auditory areas in the temporal lobe are affected by HIV regardless of speech perception ability. Increased temporal FC in HIV+ individuals might reflect functional compensation to achieve normal primary auditory perception. Furthermore, increased frontal FC in the HIV+SPabnl group compared with the HIV+SPnl group suggest that speech-in-noise perception difficulties in HIV-infected adults also affect areas involved in higher-level cognition, providing imaging evidence consistent with the hypothesis that HIV-related neurocognitive deficits can include central auditory processing deficits.

Corrigendum: Increased Right Frontal Brain Activity During the Mandarin Hearing-in-Noise Test.

[This corrects the article DOI: 10.3389/fnins.2020.614012.].

HIV-Associated Structural and Functional Brain Alterations in Homosexual Males.

PURPOSE: Neuroimaging elucidations have shown structural and functional brain alterations in HIV-infected (HIV+) individuals when compared to HIV-negative (HIV-) controls. However, HIV- groups used in previous studies were not specifically considered for sexual orientation, which also affects the brain structures and functions. The current study aimed to characterize the brain alterations associated with HIV infection while controlling for sexual orientation. METHODS: Forty-three HIV+ and 40 HIV- homosexual men (HoM) were recruited and underwent resting-state MRI scanning. Group differences in gray matter volume (GMV) were assessed using a voxel-based morphometry analysis. Brain regions with the altered GMV in the HIV+ HoM group were then taken as regions of interest in a seed-based analysis to identify altered functional connectivity. Furthermore, the amplitude of low-frequency fluctuation (ALFF) and regional homogeneity values were compared between the two groups to evaluate the HIV-associated functional abnormalities in local brain regions. RESULTS: HIV+ HoM showed significantly increased GMV in the bilateral parahippocampal gyrus and amygdala, and decreased GMV in the right inferior cerebellum, compared with the HIV- HoM. The brain regions with increased GMV were hyper-connected with the left superior cerebellum, right lingual gyrus, and left precuneus in the HIV+ HoM. Moreover, the ALFF values of the right fusiform gyrus, and left parahippocampal gyrus were increased in the HIV+ HoM. The regional homogeneity values of the right anterior cingulate and paracingulate gyri, and left superior cerebellum were decreased in the HIV+ HoM. CONCLUSION: When the study population was restricted to HoM, HIV+ individuals exhibited structural alterations in the limbic system and cerebellum, and functional abnormalities in the limbic, cerebellum, and visual network. These findings complement the existing knowledge on the HIV-associated neurocognitive impairment from the previous neuroimaging studies by controlling for the potential confounding factor, sexual orientation. Future studies on brain alternations with the exclusion of related factors like sexual orientation are needed to understand the impact of HIV infection on neurocognitive function more accurately.

MECP2 Duplication Causes Aberrant GABA Pathways, Circuits and Behaviors in Transgenic Monkeys: Neural Mappings to Patients with Autism.

MECP2 gain-of-function and loss-of-function in genetically engineered monkeys recapitulates typical phenotypes in patients with autism, yet where MECP2 mutation affects the monkey brain and whether/how it relates to autism pathology remain unknown. Here we report a combination of gene-circuit-behavior analyses including MECP2 coexpression network, locomotive and cognitive behaviors, and EEG and fMRI findings in 5 MECP2 overexpressed monkeys (Macaca fascicularis; 3 females) and 20 wild-type monkeys (Macaca fascicularis; 11 females). Whole-genome expression analysis revealed MECP2 coexpressed genes significantly enriched in GABA-related signaling pathways, whereby reduced ß-synchronization within fronto-parieto-occipital networks was associated with abnormal locomotive behaviors. Meanwhile, MECP2-induced hyperconnectivity in prefrontal and cingulate networks accounted for regressive deficits in reversal learning tasks. Furthermore, we stratified a cohort of 49 patients with autism and 72 healthy controls of 1112 subjects using functional connectivity patterns, and identified dysconnectivity profiles similar to those in monkeys. By establishing a circuit-based construct link between genetically defined models and stratified patients, these results pave new avenues to deconstruct clinical heterogeneity and advance accurate diagnosis in psychiatric disorders.SIGNIFICANCE STATEMENT Autism spectrum disorder (ASD) is a complex disorder with co-occurring symptoms caused by multiple genetic variations and brain circuit abnormalities. To dissect the gene-circuit-behavior causal chain underlying ASD, animal models are established by manipulating causative genes such as MECP2 However, it is unknown whether such models have captured any circuit-level pathology in ASD patients, as demonstrated by human brain imaging studies. Here, we use transgenic macaques to examine the causal effect of MECP2 overexpression on gene coexpression, brain circuits, and behaviors. For the first time, we demonstrate that the circuit abnormalities linked to MECP2 and autism-like traits in the monkeys can be mapped to a homogeneous ASD subgroup, thereby offering a new strategy to deconstruct clinical heterogeneity in ASD.

Increased Right Frontal Brain Activity During the Mandarin Hearing-in-Noise Test.

PURPOSE: Previous studies have revealed increased frontal brain activation during speech comprehension in background noise. Few, however, used tonal languages. The normal pattern of brain activation during a challenging speech-in-nose task using a tonal language remains unclear. The Mandarin Hearing-in-Noise Test (HINT) is a well-established test for assessing the ability to interpret speech in background noise. The current study used Mandarin HINT (MHINT) sentences and functional magnetic resonance imaging (fMRI) to assess brain activation with MHINT sentences. METHODS: Thirty native Mandarin-speaking subjects with normal peripheral hearing were recruited. Functional MRI was performed while subjects were presented with either HINT "clear" sentences with low-level background noise [signal-to-noise ratio (SNR) = +3 dB] or "noisy" sentences with high-level background noise (SNR = -5 dB). Subjects were instructed to answer with a button press whether a visually presented target word was included in the sentence. Brain activation between noisy and clear sentences was compared. Activation in each condition was also compared to a resting, no sentence presentation, condition. RESULTS: Noisy sentence comprehension showed increased activity in areas associated with tone processing and working memory, including the right superior and middle frontal gyri [Brodmann Areas (BAs) 46, 10]. Reduced activity with noisy sentences was seen in auditory, language, memory and somatosensory areas, including the bilateral superior and middle temporal gyri, left Heschl's gyrus (BAs 21, 22), right temporal pole (BA 38), bilateral amygdala-hippocampus junction, and parahippocampal gyrus (BAs 28, 35), left inferior parietal lobule extending to left postcentral gyrus (BAs 2, 40), and left putamen. CONCLUSION: Increased frontal activation in the right hemisphere occurred when comprehending noisy spoken sentences in Mandarin. Compared to studies using non-tonal languages, this activation was strongly right-sided and involved subregions not previously reported. These findings may reflect additional effort in lexical tone perception in this tonal language. Additionally, this continuous fMRI protocol may offer a time-efficient way to assess group differences in brain activation with a challenging speech-in-noise task.

Sorghumol triterpene inhibits the growth of circulating renal cancer cells by promoting cell apoptosis, G2/M cell cycle arrest and downregulating m-TOR/PI3K/AKT signalling pathway.

PURPOSE: To investigate the growth inhibitory effect of Sorghumol on the circulating renal cancers cells and to investigate the underlying mechanisms including its effects on apoptosis, cell cycle phase distribution and m-TOR/PI3K/AKT signalling pathway. METHODS: The antiproliferative effects were assessed by WST-1 and colony formation assay. Apoptosis was detected by the Hoechst and AO/EB staining using fluorescence microscopy. Cell cycle analysis was carried out by flow cytometry. Protein expression was checked by western blotting. RESULTS: The results revealed that Sorghumol inhibited the growth of the renal cancer cell (RCC) line A498 and circulating RCCs. However, more profound effects were observed on the RCC cells. The anticancer effects were found to be due to induction of apoptosis. Moreover, Sorghumol could also caused G2/M cell cycle arrest of the RCC cells. Besides, examination of the effect of Sorghumol on m-TOR/PI3K/AKT revealed that Sorghumol inhibited the expression of p-mTOR, p-PI3K and p-AKT in a concentration-dependent manner. CONCLUSION: Taken together, we conclude that Sorghumol inhibited the proliferation of circulating RCCs and may therefore prove to be an important lead molecule for the treatment of renal cancer.

Isoflurane-Induced Burst Suppression Increases Intrinsic Functional Connectivity of the Monkey Brain.

Animal functional magnetic resonance imaging (fMRI) has provided key insights into the physiological mechanisms underlying healthy and diseased brain states. In non-human primates, resting-state fMRI studies are commonly conducted under isoflurane anesthesia, where anesthetic concentration is used to roughly infer anesthesia depth. However, within the recommended isoflurane concentration range (1.00-1.50%), the brain state can switch from moderate anesthesia characterized by stable slow wave (SW) electroencephalogram (EEG) signals to deep anesthesia characterized by burst suppression (BS), which is electrophysiologically distinct from the resting state. To confirm the occurrence rate of BS activity in common setting of animal fMRI study, we conducted simultaneous resting-state EEG and fMRI experiments on 16 monkeys anesthetized using 0.80-1.30% isoflurane, and detected BS activity in two of them. Datasets either featured with BS or SW activity from these two monkeys were analyzed to investigate the intrinsic functional connectivity (FC) patterns during BS. In datasets with BS activity, we observed robust coupling between the BS pattern (the binary alternation between burst and suppression activity in EEG signal) and filtered BOLD signals in most brain areas, which was associated with a non-specific enhancement in whole brain connectivity. After eliminating the BS coupling effect by regressing out the BS pattern, we detected an overall increase in FC with a few decreased connectivity compared to datasets with SW activity. These affected connections were preferentially distributed within orbitofrontal cortex, between orbitofrontal and prefrontal/cingulate/occipital cortex, and between temporal and parietal cortex. Persistence of the default mode network and recovery of thalamocortical connections were also detected under deep anesthesia with BS activity. Taken together, the observed spatially specific alterations in BS activity induced by isoflurane not only highlight the necessity of EEG monitoring and careful data preprocessing in fMRI studies on anesthetized animals, but also advance our understanding of the underlying multi-phased mechanisms of anesthesia.

HNF1B expression regulates ECI2 gene expression, potentially serving a role in prostate cancer progression.

Prostate cancer is the most common form of cancer in men, with increased incidence rates observed in older individuals. Prostate cancer is primarily driven via activation of the androgen receptor (AR), the principal transcriptional factor governing prostate cancer cellular programming and its associated metabolism. One of the downstream targets of AR is hepatocyte nuclear factor-1ß (HNF1B), an important oncogenic transcription factor in prostate cancer. In the present study, the regulatory role of HNF1B in enoyl-CoA-(Δ) isomerase 2 (ECI2) expression in the transgenic adenocarcinoma of the mouse prostate (TRAMP) mouse model was investigated. Using this model, tumor progression and associated pathological alterations at 12, 18 and 24 weeks were analyzed. Histological sectioning revealed pathological alterations over time, including thickening of glandular epithelial cells (12 weeks), increases in cellular proliferation (18 weeks), and extensive thickening and hardening of the tissue layer (24 weeks). Expression levels of HNF1B and ECI2 proteins were validated by immunohistochemistry and western blotting at different stages of prostate cancer development. HNF1B and ECI2 exhibited minimal differences in protein expression at 12 weeks in TRAMP+ mice. However, by 18 weeks, TRAMP+ mice exhibited multi-fold increases in HNF1B expression levels, along with downregulation of ECI2. These effects were reversed at 24 weeks, indicating an important time-dependent regulation of gene expression. Taken together, these results demonstrated that upon tumor progression, the initial tumor-protective effect of HNF1B is lost along with downregulated expression of HNF1B and increased expression of ECI2.

Significant association between interleukin-10 gene polymorphisms and cervical cancer risk: a meta-analysis.

Previous studies have suggested that interleukin-10 (IL-10) polymorphisms may be associated with an increased risk of developing cervical cancer. However, the published results on this subject matter are controversial. The aim of this study was to conduct a meta-analysis of published reports to more precisely investigate the relationship between IL-10 polymorphisms and cervical cancer risk. Five online databases (PubMed, Embase, Web of SCI, CNKI and Wanfang) were searched, and seventeen articles with sufficient quantitative information were included in our meta-analysis. The odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the association between IL-10 polymorphisms and cervical cancer risk. Publication bias, sensitivity and cumulative analyses were also performed to support our findings. Overall, there was a significant association between the IL-10 -1082A > G polymorphism and cervical cancer risk observed in the total population (G vs. A: OR = 1.60, 95% CI = 1.12-2.29, P = 0.01, I2 = 92.3%; AG vs. AA: OR = 1.34, 95% CI = 1.04-1.74, P = 0.03, I2 = 65.9%; AG + GG vs. AA: OR = 1.58, 95% CI = 1.11-2.25, P = 0.01, I2 = 84.4%), and the same results were obtained in the subgroup analysis. Moreover, the IL-10 -819 T > C polymorphism exhibited a significant, protective effect against cervical cancer. In summary, our meta-analysis suggests that IL-10 polymorphisms may play a variety of roles in regard to cervical cancer risk, especially in Asians.

Blockage of RelB expression by gene silencing enhances the radiosensitivity of androgen­independent prostate cancer cells.

Levels of the nuclear factor­kappa B (NF­κB) alternative pathway member RelB have been shown to correlate with the effect of radiation therapy in prostate cancer. RelB expression was evaluated by immunohistochemistry in normal prostate, benign prostate hyperplasia and prostate cancer specimens. RM­1 cells were pretreated with RelB siRNA prior to radiation therapy, and RelB expression in cytoplasmic and nuclear extracts was detected by real­time polymerase chain reaction and western blot analysis. The apoptotic rates of experimental RM­1 cell groups were assessed by flow cytometry. A clonogenic growth array was used to evaluate the radiosensitivity of RM­1 cell groups. The NF­κB family member RelB was expressed at a high level in prostate cancer specimens. Compared with irradiated control cells, RM­1 cells transfected with RelB siRNA and treated with radiation therapy demonstrated a significant downregulation of RelB expression in the cytoplasm and nucleus. Notably, flow cytometry revealed that pretreatment of RM­1 cells with RelB siRNA enhanced the apoptotic rate in response to radiation therapy compared with controls. Clonogenic growth assay results revealed enhanced radiosensitivity of RelB siRNA cells at various dosage points compared with control groups. Blockage of the alternative NF­κB pathway via RelB silencing is a promising approach to enhance the radiosensitivity of prostate cancer.

[RelB-siRNA enhanced the radiosensitivity of murine prostate cancer cell line RM-1].

OBJECTIVE: To explore the transfecting effects of RelB small interfering RNA (RelB-siRNA) on murine prostate cancer cell line RM-1 sensitivity of radiotherapy. METHODS: The RM-1 cells were divided into RelB-siRNA vector, empty vector, non-transfection and normal groups. After transfection, the first three groups were irradiated by X ray. Clone formation array method was used to measure the surviving fraction and the relevant parameter values after 0, 2, 4, 6, 8 Gy irradiation. Apoptotic rate was measured via Annexin V/PI flow cytometry after 6 Gy irradiation. The level of RelBmRNA was estimated by real-time polymerase chain reaction (PCR) after 6 Gy irradiation. And the RelB protein of cytoplasm and nucleus was detected by Western blot after 6 Gy irradiation. RESULTS: Clone formation array showed that RelB group at each dose point corresponding to the survival fraction were lower that the empty vector nd non-transfection groups. The D0, Dq and SF2 values of RelB group were 1.68, 0.60, 0.43, lower than those of empty vector group 1.92, 3.08, 0.89 and non-transfection group 1.93, 2.76, 0.84. Annexin V/PI flow cytometry demonstrated that the apoptotic rate of RelB group was 15.27% ± 1.62% and it was significantly higher than the non-transfection group 7.90% ± 1.50% and the empty vector group 8.40% ± 0.69% respectively (P < 0.01) .Real-time PCR indicated that RelB-mRNA amplification of RelB group was 1.18 ± 0.03 and it was significantly lower than the non-transfection group 2.10 ± 0.61 and the empty vector group 1.97 ± 0.66 respectively (P < 0.01) .Western blot suggested that cytoplasmic gray-scale ratio of RelB group was 0.50 ± 0.08 and it was significantly lower than the non-transfection 1.77 ± 0.19 and the empty group 1.52 ± 0.12 respectively (P < 0.01) . And the nuclear gray-scale radio of the RelB group was 0.18 ± 0.03 and it was significantly lower than the non-transfection group 0.61 ± 0.12 and the empty group 0.54 ± 0.13 respectively (P < 0.01) . The RelB protein inhibition rates of cytoplasmic and nuclear RelB-siRNA were 71.8% and 70.4% respectively. CONCLUSION: RelB-siRNA can effectively inhibit the RelB expression of murine prostate cancer cell line RM-1 and significantly increase its sensitivity to radiotherapy.

Role of autophagy in acute myeloid leukemia therapy / 癌症

Despite its dual role in determining cell fate in a wide array of solid cancer cell lines, autophagy has been robustly shown to suppress or kill acute myeloid leukemia cells via degradation of the oncogenic fusion protein that drives leukemogenesis. However, autophagy also induces the demise of acute leukemia cells that do not express the known fusion protein, though the molecular mechanism remains elusive. Nevertheless, since it can induce cooperation with apoptosis and differentiation in response to autophagic signals, autophagy can be manipulated for a better therapy on acute myeloid leukemia.

Tolerogenic dendritic cells generated by RelB silencing using shRNA prevent acute rejection.

It is well known that adoptive transfer of donor-derived tolerogenic dendritic cells (DCs) helps to induce immune tolerance. RelB, one of NF-κB subunits, is a critical element involved in DC maturation. In the present study, our results showed tolerogenic DCs could be acquired via silencing RelB using small interfering RNA. Compared with imDCs, the tolerogenic DCs had more potent ability to inhibit mixed lymphocyte reaction (MLR) and down-regulate Th1 cytokines and prompt the production of Th2 cytokines. They both mediated immune tolerance via the increased of T cell apoptosis and generation of regulatory T cells. Administration of donor-derived tolerogenic DCs significantly prevented the allograft rejection and prolonged the survival time in a murine heart transplantation model. Our results demonstrate donor-derived, RelB-shRNA induced tolerogenic DCs can significantly induce immune tolerance in vitro and in vivo.

Lentiviral-mediated shRNA against RelB induces the generation of tolerogenic dendritic cells.

OBJECTIVE: Lentiviral-mediated shRNA against RelB was used to produce tolerogenic dendritic cells from murine bone marrow derived dendritic cells (BMDCs). METHOD: RelB expression in the BMDCs was silenced by lentivirus carrying RelB shRNA. The apoptosis rate and surface markers of DCs were assessed by flow cytometry. IL-12,IL-10,TGF-ß1 secreted by DCs and DNA binding capacity of NF-κB subunits in the nucleus were measured by ELISA, independently. MLR was used to analyze the capacity of DCs to inhibit immune response. RESULTS: RelB expression was significantly inhibited in DCs following lentiviral mediated delivery of RelB specific shRNA. The RelB shRNA-DC produced lower IL-12 and higher IL-10 than mature dendritic cells (mDCs) and silencing control DCs. There was no difference in the apoptosis rate between shRNA RelB-DCs and mDCs. The expression levels of co-stimulatory molecules (CD80, CD86 and CD83) and MHC-II class molecule were lower in the RelB shRNA-DCs than in the mDCs and silencing control DCs. In addition, RelB shRNA also inhibited the RelB DNA binding capacity but had no effect on other NF-κB subunits. The shRNA RelB-DCs can significantly inhibit mixed lymphocyte reaction (MLR) and down-regulate Th1 cytokines and prompt the production of Th2 cytokines. CONCLUSION: Our results indicate RelB shRNA transfection of DCs can induce the immature status, and produce tolerogenic DCs.