FDA compound library screening Baicalin upregulates TREM2 for the treatment of cerebral ischemia-reperfusion injury.

Acute ischemic stroke (AIS) is a leading cause of global incidence and mortality rates. Oxidative stress and inflammation are key factors in the pathogenesis of AIS neuroinjury. Therefore, it is necessary to develop drugs that target neuroinflammation and oxidative stress in AIS. The Triggering Receptor Expressed on Myeloid Cells 2 (TREM2), primarily expressed on microglial cell membranes, plays a critical role in reducing inflammation and oxidative stress in AIS. In this study, we employed a high-throughput screening (HTS) strategy to evaluate 2625 compounds from the (Food and Drug Administration) FDA library in vitro to identify compounds that upregulate the TREM2 receptor on microglia. Through this screening, we identified Baicalin as a potential drug for AIS treatment. Baicalin, a flavonoid compound extracted and isolated from the root of Scutellaria baicalensis, demonstrated promising results. Next, we established an in vivo mouse model of cerebral ischemia-reperfusion injury (MCAO/R) and an in vitro microglia cell of oxygen-glucose deprivation reperfusion (OGD/R) to investigate the role of Baicalin in inflammation injury, oxidative stress, and neuronal apoptosis. Our results showed that baicalin effectively inhibited microglia activation, reactive oxygen species (ROS) production, and inflammatory responses in vitro. Additionally, baicalin suppressed neuronal cell apoptosis. In the in vivo experiments, baicalin not only improved neurological functional deficits and reduced infarct volume but also inhibited microglia activation and inflammatory responses. Overall, our findings demonstrate the efficacy of Baicalin in treating MCAO/R by upregulating TREM2 to reduce inflammatory responses and inhibit neuronal apoptosis.

Multiomics analyses of two Leonurus species illuminate leonurine biosynthesis and its evolution.

The Lamiaceae family is renowned for its terpenoid-based medicinal components, but Leonurus, which has traditional medicinal uses, stands out for its alkaloid-rich composition. Leonurine, the principal active compound found in Leonurus, has demonstrated promising effects in reducing blood lipids and treating strokes. However, the biosynthetic pathway of leonurine remains largely unexplored. Here, we present the chromosome-level genome sequence assemblies of Leonurus japonicus, known for its high leonurine production, and Leonurus sibiricus, characterized by very limited leonurine production. By integrating genomics, RNA sequencing, metabolomics, and enzyme activity assay data, we constructed the leonurine biosynthesis pathway and identified the arginine decarboxylase (ADC), uridine diphosphate glucosyltransferase (UGT), and serine carboxypeptidase-like (SCPL) acyltransferase enzymes that catalyze key reactions in this pathway. Further analyses revealed that the UGT-SCPL gene cluster evolved by gene duplication in the ancestor of Leonurus and neofunctionalization of SCPL in L. japonicus, which contributed to the accumulation of leonurine specifically in L. japonicus. Collectively, our comprehensive study illuminates leonurine biosynthesis and its evolution in Leonurus.

Gelatin films functionalized by lignocellulose nanocrystals-tannic acid stabilized Pickering emulsions: Influence of cinnamon essential oil.

The Pickering emulsions containing cinnamon essential oil (CEO) stabilized by lignocellulose nanocrystals-tannic acid (LCNC-TA) complexes were used to improve properties of gelatin film. The influences of various volume proportion mixed oil (sunflower oil/CEO 1:0, 5:1, 2:1 and 1:1) were investigated. Introducing CEO reduced the droplet size approximately from 57 to 30 µm, facilitating droplet distribution in film matrix. With increasing CEO proportion, the surface structure of emulsion films became uniform without micropores or cavities, showing good compatibility with film matrix during film-forming process. Furthermore, increasing CEO proportion improved tensile strength (TS, 3.75-4.61 MPa) and water vapor permeability (WVP, 9.16 × 10-12-7.61 × 10-12 g·cm-1s-1Pa-1) of emulsion films. Besides, the UV blocking, antioxidant and antibacterial properties of emulsion films improved as CEO proportion increased. Compared with the control gelatin film, the loss of CEO in emulsion films effectively decreased through pre-embedding approach by Pickering emulsion method.

Effects of Collagen Antibacterial Functional Dressing plus Continuous Nursing on Lower Extremity Skin Injury Caused by Norepinephrine in Patients with Septic Shock.

Background: This study was designed to explore the effects of collagen antibacterial functional dressing plus continuous care on norepinephrine-induced lower extremity skin injury in patients with septic shock. Methods: In this prospective, randomized, controlled study, 120 patients with septic shock receiving norepinephrine in our hospital from February 2020 to February 2021 were recruited. All the enrollments were randomized into the experimental group (n = 60) and the control group (n = 60). The control group received continuous care, while the experimental group additionally received collagen antibacterial functional dressing. Outcome measures included skin sensation scores, incidence of lower extremity skin injuries, recovery time, inflammatory factor levels, and care satisfaction. Results: Collagen antibacterial functional dressing plus continuous care resulted in significantly lower skin sensation scores and a lower incidence of skin injuries versus continuous care alone. Patients in the experimental group had faster recovery of lower extremity skin injury than those in the control group. Collagen antibacterial functional dressing plus continuous care was associated with significantly lower levels of inflammatory factors and a higher satisfaction rate than continuous care alone. Conclusion: Collagen antibacterial functional dressing plus continuous care improves the local skin condition of patients with septic shock receiving norepinephrine, regulates the levels of inflammatory factors, reduces the risk of skin injuries, and enhances care satisfaction.

Efficacy and safety of reduning injection combined with azithromycin in the treatment of mycoplasma pneumonia among children: A systematic review and meta-analysis.

BACKGROUND: Reduning (RDN) injection is a well-known traditional Chinese medicine (TCM) preparation that can be used as an alternative to antibiotics with synergistic and toxicity-reducing effects. In China, RDN is widely used in the combined treatment of infectious diseases. OBJECTIVE: To evaluate the clinical efficacy of RDN combined with azithromycin (AZM) for the treatment of mycoplasma pneumonia (MP) among children and to determine its safety, providing an evidence-based reference for clinical treatment. METHODS: Eight databases were searched, including 4 English databases, namely, PubMed, EMBASE, the Cochrane Library, and Web of Science, and 4 Chinese databases, namely, China National Knowledge Infrastructure (CNKI), Wanfang, China Science and Technology Journal Database (CQVIP), and Sino-Med. Randomized controlled trials (RCTs) were included in which RDN was combined with AZM for the treatment of MP pediatric patients. A comprehensive search was performed from the inception of each database until April 25, 2022. RESULTS: A total of 20 studies covering 1628 children were included. Meta-analysis showed that the clinical effectiveness rate (RR = 1.20, 95% CI [1.15, 1.26], I2 = 0%), time elapsed until disappearance of cough (MD = -2.04, 95% CI [-2.67, -1.41], I2 = 91%), time elapsed until disappearance of lung rales (MD = -2.55, 95% CI [-3.12, -1.98], I2 = 95%), time elapsed until reduction of fever (MD = -1.93, 95% CI [-2.37, -1.49], I2 = 92%), TNF-α level after treatment (SMD = -1.17, 95% CI [-1.96, -0.39], I2 = 97%), and IL-6 levels after treatment (SMD = -2.65, 95% CI [-3.51, -1.78], I2 = 97%) of the combined treatment of MPP were superior to those of other methods, and incidence of adverse reactions (RR = 0.75, 95% CI [0.56, 1.00], I2 = 0%) showed statistically significant differences. CONCLUSION: RDN combined with AZM for the treatment of MP among children results in increased clinical efficacy with high safety.

Exploration of Dipeptidyl Peptidase-IV (DPP-IV) Inhibitory Peptides from Silkworm Pupae (Bombyx mori) Proteins Based on In Silico and In Vitro Assessments.

This study aimed at exploring dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides from silkworm pupae proteins by in silico analysis and in vitro assessments. In silico analysis of 274 silkworm pupae proteomes indicated that DPP-IV inhibitory peptides can be released from silkworm pupae proteins. In vitro assessments revealed that pepsin and bromelain led to better production of DPP-IV inhibitory peptides from silkworm pupae protein. Notably, peptide fractions (<1 kDa) from pepsin- and bromelain-treated hydrolysates exhibited more potent DPP-IV inhibitory activities. Two novel DPP-IV inhibitory peptides (Leu-Pro-Pro-Glu-His-Asp-Trp-Arg and Leu-Pro-Ala-Val-Thr-Ile-Arg) were identified by LC-MS/MS with IC50 values of 261.17 and 192.47 µM, respectively. Enzyme kinetics data demonstrated that these two peptides displayed a mixed-type DPP-IV inhibition mode, which was further validated by molecular docking data. Overall, in silico analysis combined with in vitro assessments can serve as an effective and rapid approach for discovery of DPP-IV peptides from silkworm pupae proteins.

Metabolic analysis of the asparagine and glutamine dynamics in an industrial Chinese hamster ovary fed-batch process.

Chinese hamster ovary (CHO) cell lines are grown in cultures with varying asparagine and glutamine concentrations, but further study is needed to characterize the interplay between these amino acids. By following 13 C-glucose, 13 C-glutamine, and 13 C-asparagine tracers using metabolic flux analysis (MFA), CHO cell metabolism was characterized in an industrially relevant fed-batch process under glutamine supplemented and low glutamine conditions during early and late exponential growth. For both conditions MFA revealed glucose as the primary carbon source to the tricarboxylic acid (TCA) cycle followed by glutamine and asparagine as secondary sources. Early exponential phase CHO cells prefer glutamine over asparagine to support the TCA cycle under the glutamine supplemented condition, while asparagine was critical for TCA activity for the low glutamine condition. Overall TCA fluxes were similar for both conditions due to the trade-offs associated with reliance on glutamine and/or asparagine. However, glutamine supplementation increased fluxes to alanine, lactate and enrichment of glutathione, N-acetyl-glucosamine and pyrimidine-containing-molecules. The late exponential phase exhibited reduced central carbon metabolism dominated by glucose, while lactate reincorporation and aspartate uptake were preferred over glutamine and asparagine. These 13 C studies demonstrate that metabolic flux is process time dependent and can be modulated by varying feed composition.

A New Two-Step Anesthesia for 23- or 25-Gauge Vitrectomy Surgery: A Prospective, Randomized Clinical Trial.

OBJECTIVE: To investigate the safety and efficacy of topical anesthesia combined with subconjunctival anesthesia (termed two-step anesthesia) for 23- or 25-gauge pars plana vitrectomy or other posterior segment surgery. METHODS: Patients (n = 90) requiring 23-/25-gauge vitrectomy or other posterior segment surgery were randomized into 3 groups. Group 1 received peribulbar anesthesia, group 2 received retrobulbar anesthesia and group 3 received two-step anesthesia. A 5-point visual analog pain scale (VAPS) was used to measure self-report of patient pain. Complications were recorded for subsequent analysis. RESULTS: VAPS scores for overall intraoperative pain ranged from 0 to 3 (1.07 ± 1.07) in group 1, from 0 to 2 (0.69 ± 0.93) in group 2 and from 0 to 3 (1.06 ± 0.98) in group 3. Assessment of surgeon discomfort score ranged from 0 to 2 (0.31 ± 0.66) in group 1, from 0 to 3 (0.38 ± 0.82) in group 2 and from 0 to 2 (0.47 ± 0.62) in group 3. Both scores reveal no significant difference among the 3 groups. While there were no complications noted in group 1, there was an ocular perforation in group 2. Additionally, there were no complications in group 3 related to the anesthetic technique. CONCLUSIONS: Results suggest that two-step anesthesia is a safe and effective anesthetic approach for selected patients undergoing 23- or 25-gauge pars plana vitrectomy or other posterior segment surgeries. It may offer a viable alternative to peribulbar anesthesia and retrobulbar anesthesia for carefully selected 23- or 25-gauge cannular-access ocular surgeries.

Complete chloroplast genome sequence of Pinellia ternata (Thunb.) Breit, a medicinal plants to China.

Pinellia ternata (Thunb.) Breit is one of the commonly used traditional Chinese medicine with tuber as medicine. We report herein the complete chloroplast genome sequence of Pinellia ternata (Thunb.) Breit. It is length of 167,280 bp, which contained a small single-copy (SSC) region of 23,618 bp and a large single-copy (LSC) region of 92,450 bp, separated by two copies of an inverted repeat (IR) of 25,606 bp. The chloroplast genome contains 113 unique genes, including 79 PCG, 4 rRNA genes, and 30 tRNA genes. In addition, 19 genes contained one or two introns, which of those including 13 PCG genes possess a single intron and 2 PCG genes harbor two introns; and 6 tRNA genes harbor a single intron. In this study, Pinellia ternata is sister to Pinellia pedatisecta and clustered within the group consisting of the species that belong to Araceae.

Complete chloroplast genome sequence of Bletilla striata (Thunb.) Reichb. f., a Chinese folk medicinal plant.

Bletilla striata (Thunb.) Reichb. f. is one of the commonly used traditional Chinese medicine with tuber as medicine. We report herein the complete chloroplast genome sequence of Bletilla striata (Thunb.) Reichb. f. It has a length of 159,491 bp, which contained a small single-copy (SSC) region of 18,778 bp and a large single-copy (LSC) region of 87,139 bp, separated by two copies of an inverted repeat (IR) of 26,787 bp. The chloroplast genome contains 114 unique genes, including 80 PCG, 30 tRNA, and 4 rRNA genes. In addition, 18 genes contained one or two introns, which of those including 10 PCG genes possess a single intron, and 2 PCG genes harbor two introns; and 6 tRNA genes harbor a single intron. In this study, Bletilla stariata is sister to Bletilla formosana and clustered within the group consisting of the species that belong to Orchiidaceae.

Characterization of the complete chloroplast genome of Allium mongolicum.

Allium mongolicum is a kind of wild vegetable with high nutritional value and even a traditional Chinese medicine. Here, we reported the complete chloroplast genome sequence of Allium mongolicum. The size of the chloroplast genome is 153,376 bp in length, including a large single copy region (LSC) of 82,912 bp, a small single copy region (SSC) of 18,054 bp, and a pair of inverted repeated regions of 26,205 bp. The Allium mongolicum chloroplast genome encodes 115 genes, including 69 protein-coding genes, 38 tRNA genes, and eight rRNA genes. Phylogenetic tree showed that Allium mongolicum is closely related to Allium przewalskianum.

Immunogenic cell death in cancer therapy: Present and emerging inducers.

In the tumour microenvironment (TME), immunogenic cell death (ICD) plays a major role in stimulating the dysfunctional antitumour immune system. Chronic exposure of damage-associated molecular patterns (DAMPs) attracts receptors and ligands on dendritic cells (DCs) and activates immature DCs to transition to a mature phenotype, which promotes the processing of phagocytic cargo in DCs and accelerates the engulfment of antigenic components by DCs. Consequently, via antigen presentation, DCs stimulate specific T cell responses that kill more cancer cells. The induction of ICD eventually results in long-lasting protective antitumour immunity. Through the exploration of ICD inducers, recent studies have shown that there are many novel modalities with the ability to induce immunogenic cancer cell death. In this review, we mainly discussed and summarized the emerging methods for inducing immunogenic cancer cell death. Concepts and molecular mechanisms relevant to antitumour effects of ICD are also briefly discussed.

Comparison of triterpene compounds of four botanical parts from Poria cocos (Schw.) wolf using simultaneous qualitative and quantitative method and metabolomics approach.

Poria cocos (Schw.) Wolf (PCW) is a widely used traditional Chinese medicine and dietary supplement. Its four parts including Poriae Cutis (PC), Rubra Poria (RP), White Poria (WP) and Poria cum Radix Pini (PRP) have different pharmacological effects and clinical applications. It is necessary to establish analytical platforms for differentiating the chemical composition of four botanical parts for the rational utilization. We established a simultaneous qualitative and quantitative method based on UHPLC-MS combined metabolomics approach to give an explanation of the distribution of triterpene compounds in four parts. Eight triterpene compounds were determined absolutely and a total of 51 triterpene compounds were tentatively identified in PCW. PC and PRP showed a quite clear discrimination by the principal component analysis (PCA) and orthogonal projections to latent structures-discriminant analysis (OPLS-DA) and twelve differential compounds were found. Four compounds including poricoic acid D, 16α-hydroxydehydrotrametenolic acid, 3-epidehydrotumulosic acid, 25-hydroxypolyporenic acid C were speculated to be related to diuretic effects.

Comparative analysis of proteomic and metabolomic profiles of different species of Paris.

An extract prepared from species of Paris is the most widely consumed herbal product in China. The genus Paris includes a variety of genotypes with different medicinal component contents but only two are defined as official sources. Closely related species have different medicinal properties because of differential expression of proteins and metabolites. To better understand the molecular basis of these differences, we examined proteomic and metabolomic changes in rhizomes of P. polyphylla var. chinensis, P. polyphylla var. yunnanensis, and P. fargesii var. fargesii using a technique known as sequential window acquisition of all theoretical mass spectra as well as gas chromatography-time-of-flight mass spectrometry. In total, 419 proteins showed significant abundance changes, and 33 metabolites could be used to discriminate Paris species. A complex analysis of proteomic and metabolomic data revealed a higher efficiency of sucrose utilization and an elevated protein abundance in the sugar metabolic pathway of P. polyphylla var. chinensis. The pyruvate content and efficiency of acetyl-CoA-utilization in saponin biosynthesis were also higher in P. polyphylla var. chinensis than in the other two species. The results expand our understanding of the proteome and metabolome of Paris and offer new insights into the species-specific traits of these herbaceous plants. SIGNIFICANCE: The traditional Chinese medicine Paris is the most widely consumed herbal product for the treatment of joint pain, rheumatoid arthritis and antineoplastic. All Paris species have roughly the same morphological characteristics; however, different members have different medicinal compound contents. Efficient exploitation of genetic diversity is a key factor in the development of rare medicinal plants with improved agronomic traits and malleability to challenging environmental conditions. Nevertheless, only a partial understanding of physiological and molecular mechanisms of different plants of Paris can be achieved without proteomics. To better understand the molecular basis of these differences and facilitate the use of other Paris species, we examine proteomic metabolomic changes in rhizomes of Paris using the technique known as SWATH-MS and GC/TOF-MS. Our research has provided information that can be used in other studies to compare metabolic traits in different Paris species. Our findings can also serve as a theoretical basis for the selection and cultivation of other Paris species with a higher medicinal value.

Characterization of the complete chloroplast genome of Allium tuberosum.

Allium tuberosum is a popular vegetable, condiment, and even a traditional Chinese medicine. Here, the complete chloroplast genome sequence of Allium tuberosum was reported. The size of the chloroplast genome is 154,056 bp in length, including a large single copy region (LSC) of 83,068 bp, a small single copy region (SSC) of 17,958 bp, and a pair of inverted repeat (IR) regions with 26,515 bp. The Allium tuberosum chloroplast genome encodes 132 genes, including 87 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic tree analysis suggested that Allium tuberosum was closely related to Allium sativum.

Profiling of anthocyanins in transgenic purple-fleshed sweet potatoes by HPLC-MS/MS.

BACKGROUND: Anthocyanins in purple-fleshed sweet potato (PSP) are beneficial to human health. The leaf color (Lc) gene is a transcription factor involved in regulating anthocyanin biosynthesis. The anthocyanin profiles of wild-type PSP of Ayamurasaki and its three Lc-transgenic lines were investigated by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). In vitro antioxidant activities of wild-type and Lc-transgenic lines, including reducing power activity, DPPH radical scavenging activity, hydroxyl radical scavenging activity, linoleic acid autoxidation inhibition activity, ABTS free radical scavenging activity and oxygen radical absorbance capacity activity, were measured. RESULTS: The results showed that the total anthocyanin contents increased 1.5-1.9 times in three transgenic lines compared with that in wild-type PSP. Seventeen anthocyanins were found in wild-type PSP, while 19 in Lc-transgenic lines including cyanidin-based, peonidin-based and pelargonidin-based anthocyanins. Three pelargonidin-based anthocyanins were detected in three Lc-transgenic lines. Among them, the relative contents of cyanidin-based and pelargonidin-based anthocyanins increased 1.9-2.0 and 3.4-4.5 times respectively, while peonidin-based anthocyanins decreased 1.8-1.9 times in Lc-transgenic lines, compared with wild-type PSP. PSP from wild-type Ayamurasaki and three Lc-transgenic lines exhibited potent antioxidant activities, whereas there was no distinct difference among them. CONCLUSION: The transgene Lc significantly increased the content of total anthocyanins and remarkably changed the anthocyanin profiles in Ayamurasaki. Such novel and high content of anthocyanins obtained in the Lc-transgenic lines with potent antioxidant activities may provide unique functional products with potential helpful for human health. © 2017 Society of Chemical Industry.

[Trait-based responses and adaptation of Artemisia sacrorum to environmental changes].

The paper focused on Artemisia sacrorum in the stable natural plant community in three vegetation zones (forest, forest steppe and steppe) in the Yanhe River catchment. The following plant functional traits were measured at each sample site, i.e., specific leaf area (SLA), leaf tissue density (LTD), leaf nitrogen concentration (LNC), leaf phosphorus concentration (LPC), leaf nitrogen phosphorus ratio (LNP), specific root length (SRL), root tissue density (RTD), root nitrogen concentration (RNC), root phosphorus concentration (RPC) and root nitrogen phosphorus ratio (RNP). These 10 plant functional traits were chosen because they were easily measurable and adequately reflected plant survival strategies. We analyzed intraspecific differences in A. sacrorum functional traits in the different habitat zones, and the influence of climate and terrain factors on A. sacrorum functional traits. We also studied the relationships among A. sacrorum plant functional traits. The results showed that some A. sacrorum functional traits were significantly different among sample sites, such as LPC, LNP, SRL, RTD and RNP, while the other 5 functional traits had no significant differences. The functional traits were not significantly different between sites with different slopes and aspects. SLA was very significantly negatively correlated with LTD, SRL was significantly negatively correlated with RTD and RNP, RTD was significantly positively correlated with RNC and RNP, and there were no significant relationships among LTD, LNC and LNP and the other functional traits. This showed that A. sacrorum adapted to the environment by coordinating adjustment among leaf and root functional traits. Different climate factors had different effects on plant traits, with the effects of mean annual precipitation > mean annual temperature > annual average evaporation capacity.

Ideas, properties, and standards of fracture repositioning with osteopathy in traditional Mongolian medicine in China.

OBJECTIVE: To explore the unique ideas, properties, and standards of fracture repositioning with osteopathy in traditional Mongolian medicine in China. METHODS: Based on the natural life concept of "integration of universe and man", osteopathy in traditional Mongolian medicine in China uses the modern principles and methods of physiology, psychology, and biomechanics. Against this background, we explored the unique ideas, properties, and stan- dards of fracture repositioning in traditional Mongolian medicine. RESULTS: Fracture treatment with osteopathy in traditional Mongolian medicine in China is based on (a) the ideas of natural, sealed, self and dynamic repositioning of fractures; (b) the properties of structural continuity and functional completeness; (c) the standards of "integration of movement and stillness" and "force to force". CONCLUSION: The unique ideas, properties, and standards of fracture repositioning with osteopathy in traditional Mongolian medicine in China have resulted in the widespread use of such techniques and represents the future direction of the development of fracture repositioning.

[Relationships among leaf traits and their expression in different vegetation zones in Yanhe River basin, Northwest China].

This article selected zonal plant communities as the research objects in different vegetation zones in Yanhe River basin. We measured six leaf traits of the dominant species and main accompanying species in each community, and then analyzed the relationships and their changes along with environmental gradients between these traits in order to understand the plant adaptation strategies to the environment changes. The results showed that the specific leaf area was significantly negatively correlated to leaf tissue density, area-based leaf nitrogen and phosphorus concentrations, and significantly positively correlated to mass-based leaf phosphorus concentration. Both the scaling relationships among these traits and plant life strategies were different among the three vegetation zones, the scaling-dependent relationship between leaf tissue density and specific leaf area was stronger in steppe and forest-steppe zones than in forest zone, but the correlations among area-based leaf nitrogen/phosphorus concentrations and specific leaf area and leaf tissue density were more significant in forest zone than in steppe zone. In the arid grassland and forest-steppe zone, plants give priority to defensive and stress resistance strategies, and in relatively moist nutrient-rich forest zone, plants give priority to fast growth and resource optimization allocation strategies.

Enhanced endoplasmic reticulum entry of tumor antigen is crucial for cross-presentation induced by dendritic cell-targeted vaccination.

Efficient cross-presentation of protein Ags to CTLs by dendritic cells (DCs) is essential for the success of prophylactic and therapeutic vaccines. In this study, we report a previously underappreciated pathway involving Ag entry into the endoplasmic reticulum (ER) critically needed for T cell cross-priming induced by a DC-targeted vaccine. Directing the clinically relevant, melanoma Ag gp100 to mouse-derived DCs by molecular adjuvant and chaperone Grp170 substantially facilitates Ag access to the ER. Grp170 also strengthens the interaction of internalized protein Ag with molecular components involved in ER-associated protein dislocation and/or degradation, which culminates in cytosolic translocation for proteasome-dependent degradation and processing. Targeted disruption of protein retrotranslocation causes exclusive ER retention of tumor Ag in mouse bone marrow-derived DCs and splenic CD8(+) DCs. This results in the blockade of Ag ubiquitination and processing, which abrogates the priming of Ag-specific CD8(+) T cells in vitro and in vivo. Therefore, the improved ER entry of tumor Ag serves as a molecular basis for the superior cross-presenting capacity of Grp170-based vaccine platform. The ER access and retrotranslocation represents a distinct pathway that operates within DCs for cross-presentation and is required for the activation of Ag-specific CTLs by certain vaccines. These results also reinforce the importance of the ER-associated protein quality control machinery and the mode of the Ag delivery in regulating DC-elicited immune outcomes.