Cholinergic macrophages promote the resolution of peritoneal inflammation.

The non-neural cholinergic system plays a critical role in regulating immune equilibrium and tissue homeostasis. While the expression of choline acetyltransferase (ChAT), the enzyme catalyzing acetylcholine biosynthesis, has been well documented in lymphocytes, its role in the myeloid compartment is less understood. Here, we identify a significant population of macrophages (Mϕs) expressing ChAT and synthesizing acetylcholine in the resolution phase of acute peritonitis. Using Chat-GFP reporter mice, we observed marked upregulation of ChAT in monocyte-derived small peritoneal Mϕs (SmPMs) in response to Toll-like receptor agonists and bacterial infections. These SmPMs, phenotypically and transcriptionally distinct from tissue-resident large peritoneal macrophages, up-regulated ChAT expression through a MyD88-dependent pathway involving MAPK signaling. Notably, this process was attenuated by the TRIF-dependent TLR signaling pathway, and our tests with a range of neurotransmitters and cytokines failed to induce a similar response. Functionally, Chat deficiency in Mϕs led to significantly decreased peritoneal acetylcholine levels, reduced efferocytosis of apoptotic neutrophils, and a delayed resolution of peritonitis, which were reversible with exogenous ACh supplementation. Intriguingly, despite B lymphocytes being a notable ChAT-expressing population within the peritoneal cavity, Chat deletion in B cells did not significantly alter the resolution process. Collectively, these findings underscore the crucial role of Mϕ-derived acetylcholine in the resolution of inflammation and highlight the importance of the non-neuronal cholinergic system in immune regulation.

Insights into lenvatinib resistance: mechanisms, potential biomarkers, and strategies to enhance sensitivity.

Lenvatinib is a multitargeted tyrosine kinase inhibitor capable of promoting apoptosis, suppressing angiogenesis, inhibiting tumor cell proliferation, and modulating the immune response. In multiple cancer types, lenvatinib has presented manageable safety and is currently approved as an effective first-line therapy. However, with the gradual increase in lenvatinib application, the inevitable progression of resistance to lenvatinib is becoming more prevalent. A series of recent researches have reported the mechanisms underlying the development of lenvatinib resistance in tumor therapy, which are related to the regulation of cell death or proliferation, histological transformation, metabolism, transport processes, and epigenetics. In this review, we aim to outline recent discoveries achieved in terms of the mechanisms and potential predictive biomarkers of lenvatinib resistance as well as to summarize untapped approaches available for improving the therapeutic efficacy of lenvatinib in patients with various types of cancers.

PERK reprograms hematopoietic progenitor cells to direct tumor-promoting myelopoiesis in the spleen.

The spleen is an important site of hematopoietic stem/progenitor cell (HSPC) preconditioning and tumor-promoting myeloid cell generation in cancer, but the regulatory mechanism remains unclear. Here, we found that PKR-like endoplasmic reticulum kinase (PERK) mediated HSPC reprogramming into committed MDSC precursors in the spleen via PERK-ATF4-C/EBPß signaling. Pharmacological and genetic inhibition of this pathway in murine and human HSPCs prevented their myeloid descendant cells from becoming MDSCs even with subsequent exposure to tumor microenvironment (TME) factors. In mice, the selective delivery of PERK antagonists to the spleen was not only sufficient but more effective than the tumor-targeted strategy in preventing MDSC activation in the tumor, leading to profound TME reshaping and tumor regression. Clinically, HSPCs in the spleen of cancer patients exhibit increased PERK signaling correlated with enhanced myelopoiesis. Our findings indicate that PERK-mediated HSPC preconditioning plays a crucial role in MDSC generation, suggesting novel spleen-targeting therapeutic opportunities for restraining the tumor-promoting myeloid response at its source.

Fetal and maternal outcome in patients with active lupus nephritis: comparison between new-onset and pre-existing lupus nephritis.

BACKGROUND: This study aimed to investigate fetal and maternal outcomes in women with active lupus nephritis (LN). Specifically, we compared women who had new-onset LN and those with pre-existing LN during pregnancy. METHODS: Patients with active LN during pregnancy were divided into the new-onset group (LN first occurred during pregnancy) and the pre-existing group (a history of LN) on the basis of the onset time of LN. Data on clinical features, laboratory findings, and pregnancy outcome were collected and analyzed between the two groups. Multivariate logistic regression analysis was used to compare the effects of active LN on adverse pregnancy outcomes. RESULTS: We studied 73 pregnancies in 69 women between 2010 and 2019. Of these, 38 pregnancies were in the pre-existing LN group and 35 were in the new-onset group. Patients with pre-existing LN had a higher risk of composite adverse fetal outcomes than those with new-onset LN [adjusted odds ratio (ORs), 44.59; 95% confidence interval (CI), 1.21-1664.82; P = 0.039]. However, the two groups had similar adverse maternal outcomes (ORs, 1.24; 95% CI, 0.36-4.29). Serum albumin and proteinuria significantly improved after pregnancy (P < 0.001). Kaplan-Meier analysis showed that the long-term renal outcome was similar between the two groups. CONCLUSIONS: Pregnant patients with pre-existing LN were associated with a higher risk of composite adverse fetal outcomes than those with new-onset LN. However, these two groups of patients had similar adverse maternal outcomes. The long-term renal outcomes were not different after pregnancy between these two groups.

Optimized Intracellular Staining Reveals Heterogeneous Cytokine Production Ability of Murine and Human Hematopoietic Stem and Progenitor Cells.

Under stress conditions, hematopoietic stem and progenitor cells (HSPCs) can translate danger signals into a plethora of cytokine signals. These cytokines, or more precisely their combination, instruct HSPCs to modify the magnitude and composition of hematopoietic output in response to the threat, but investigations into the heterogeneous cytokine expression and regulatory mechanisms are hampered by the technical difficulty of measuring cytokine levels in HSPCs at the single-cell level. Here, we optimized a flow cytometry-based method for the simultaneous assessment of multiple intracellular cytokines in HSPCs. By selecting an optimal combination of cytokine restimulation reagents, protein transport inhibitors, and culture supplements, an optimized restimulation protocol for intracellular staining was developed. Using this method, we successfully examined expression levels of granulocyte/macrophage colony-stimulating factor (GM-CSF), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in murine and human HSPC subsets under steady-state or different stress conditions. Different cytokine expression patterns were observed, suggesting distinct regulatory modes of cytokine production dependent on the HSPC subset, cytokine, disease, organ, and species. Collectively, this technical advance may help to obtain a better understanding of the nature of HSPC heterogeneity on the basis of differential cytokine production.

Reprogramming immunosuppressive myeloid cells by activated T cells promotes the response to anti-PD-1 therapy in colorectal cancer.

Overcoming local immunosuppression is critical for immunotherapy to produce robust anti-tumor responses. Myeloid-derived suppressor cells (MDSCs) are key regulators of immunosuppressive networks and promote tumor progression. However, it remains unclear whether and how tumor-infiltrating MDSCs are shaped in response to anti-PD-1 treatment and what their impact on therapeutic efficacy is in colorectal cancer (CRC). In this study, the levels of infiltrating MDSCs were significantly higher in the non-responding organoids and were selectively reduced in the responding group, with MDSCs showing increased apoptosis and attenuated functional activity after anti-PD-1 treatment. A negative correlation between T-cell activation and MDSC function was also observed in fresh human CRC tissues. Mechanistic studies revealed that autocrine IFN-α/ß upregulated TRAIL expression on activated T cells to elicit MDSC apoptosis via the TRAIL-DR5 interaction and acted synergistically with TNF-α to inhibit MDSC function of suppressing the T-cell response through the JNK-NMDAR-ARG-1 pathway. Moreover, blockade of IFN-α/ß and TNF-α abolished the therapeutic efficacy of anti-PD-1 treatment by preserving the frequency and suppressive activity of infiltrating MDSCs in a CRC mouse model. This result suggested that reprogramming MDSCs by IFN-α/ß and TNF-α from activated T cells was necessary for successful anti-PD-1 treatment and might serve as a novel strategy to improve the response and efficacy of anticancer therapy.

Retinoic Acid Synthesis Deficiency Fosters the Generation of Polymorphonuclear Myeloid-Derived Suppressor Cells in Colorectal Cancer.

Metabolism is reprogrammed in cancer to fulfill the demands of malignant cells for cancer initiation and progression. Apart from its effects within cancer cells, little is known about whether and how reprogramed metabolism regulates the surrounding tumor microenvironment (TME). Myeloid-derived suppressor cells (MDSC) are key regulators of the TME and greatly affect tumor progression and therapeutic responses. In this study, our results revealed that retinol metabolism-related genes and enzymes were significantly downregulated in human colorectal cancer compared with adjacent colonic tissues, and tumors exhibited a defect in retinoic acid (RA) synthesis. Reduced ADH1-mediated retinol metabolism was associated with attenuated RA signaling and accumulated MDSCs in colorectal cancer tumors. Using an in vitro model, generating MDSCs from CD34+ myeloid precursors, we found that exogenous RA could abrogate the generation of polymorphonuclear MDSCs (PMN-MDSC) with negligible impact on myeloid differentiation. Mechanistically, RA could restrain the glycolytic capacity of myeloid cells, which in turn activated the AMP-activated protein kinase (AMPK) pathway, further impairing the suppressive capacity of myeloid cells. Supplementation with RA could significantly delay tumor growth, with reduced arginase-1-expressing myeloid cells and increased CD8+ and granzyme B+ T cells in both colitis-associated and implanted MC38 mouse colorectal cancer models. Our results indicated that the defect in ADH1-mediated RA synthesis could provide a possible mechanism that fosters the generation of PMN-MDSCs in colorectal cancer and that restoring RA signaling in the TME could serve as a promising therapeutic strategy to abrogate the generation of PMN-MDSCs.

Single-cell transcriptome profiling of an adult human cell atlas of 15 major organs.

BACKGROUND: As core units of organ tissues, cells of various types play their harmonious rhythms to maintain the homeostasis of the human body. It is essential to identify the characteristics of cells in human organs and their regulatory networks for understanding the biological mechanisms related to health and disease. However, a systematic and comprehensive single-cell transcriptional profile across multiple organs of a normal human adult is missing. RESULTS: We perform single-cell transcriptomes of 84,363 cells derived from 15 tissue organs of one adult donor and generate an adult human cell atlas. The adult human cell atlas depicts 252 subtypes of cells, including major cell types such as T, B, myeloid, epithelial, and stromal cells, as well as novel COCH+ fibroblasts and FibSmo cells, each of which is distinguished by multiple marker genes and transcriptional profiles. These collectively contribute to the heterogeneity of major human organs. Moreover, T cell and B cell receptor repertoire comparisons and trajectory analyses reveal direct clonal sharing of T and B cells with various developmental states among different tissues. Furthermore, novel cell markers, transcription factors, and ligand-receptor pairs are identified with potential functional regulations in maintaining the homeostasis of human cells among tissues. CONCLUSIONS: The adult human cell atlas reveals the inter- and intra-organ heterogeneity of cell characteristics and provides a useful resource in uncovering key events during the development of human diseases in the context of the heterogeneity of cells and organs.

Glutamine Deprivation Promotes the Generation and Mobilization of MDSCs by Enhancing Expression of G-CSF and GM-CSF.

Solid tumors are often challenged by hypoxic and nutrient-deprived tumor microenvironments (TME) as tumors progress, due to limited perfusion and rapid nutrient consumption. While cancer cells can demonstrate the ability to survive in nutrient-deprived conditions through multiple intrinsic alterations, it is poorly understood how nutrient-deprived cancer cells co-opt the TME to promote cancer cell survival and tumor progression. In the present study, we found that glutamine deprivation markedly potentiated the expression of G-CSF and GM-CSF in mouse mammary cancer cells. The IRE1α-JNK pathway, which is activated by glutamine starvation, was found to be important for the upregulation of these cytokines. G-CSF and GM-CSF are well-known facilitators of myelopoiesis and mobilization of hematopoietic progenitor cells (HPC). Consistently, as tumors progressed, we found that several myeloid HPC compartments were gradually decreased in the bone marrow but were significantly increased in the spleen. Mechanistically, the HPC-maintaining capacity of the bone marrow was significantly impaired in tumor-bearing mice, with lower expression of HPC maintaining genes (i.e., CXCL12, SCF, ANGPT1, and VCAM1), and reduced levels of mesenchymal stem cells and CXCL12-producing cells. Furthermore, the mobilized HPCs that displayed the capacity for myelopoiesis were also found to accumulate in tumor tissue. Tumor-infiltrating HPCs were highly proliferative and served as important sources of immunosuppressive myeloid-derived suppressor cells (MDSCs) in the TME. Our work has identified an important role for glutamine starvation in regulating the expression of G-CSF and GM-CSF, and in facilitating the generation of immunosuppressive MDSCs in breast cancer.

Immunosuppressive Immature Myeloid Cell Generation Is Controlled by Glutamine Metabolism in Human Cancer.

Tumor-associated myeloid cells are one of the prominent components of solid tumors, serving as major immune regulators for the tumor microenvironment (TME) and an obstacle for immune-checkpoint blocking (ICB) therapy. However, it remains unclear how metabolic processes regulate the generation of suppressive myeloid cells in the TME. Here, we found that hematopoietic precursor cells are enriched in the tissues of several types of human cancer and can differentiate into immature myeloid cells (IMC). Tumor-infiltrating IMCs are highly immunosuppressive, glycolytic, and proliferative, as indicated by high levels of M-CSFR, Glut1, and Ki67. To elucidate the role of metabolism in regulating the generation of IMCs, we induced suppressive IMCs from hematopoietic precursor cells with GM-CSF and G-CSF in vitro We found that the generation of suppressive IMCs was accompanied by increased glycolysis, but not affected by glucose deprivation due to alternative catabolism. Generation of IMCs relied on glutaminolysis, regardless of glucose availability. Glutamine metabolism not only supported the expansion of IMCs with glutamine-derived α-ketoglutarate but also regulated the suppressive capacity through the glutamate-NMDA receptor axis. Moreover, inhibition of glutaminase GLS1 enhanced the therapeutic efficacy of anti-PD-L1 treatment, with reduced arginase 1+ myeloid cells, increased CD8+, IFNγ+ and granzyme B+ T cells, and delayed tumor growth in an ICB-resistant mouse model. Our work identified a novel regulatory mechanism of glutamine metabolism in controlling the generation of suppressive IMCs in the TME.

The systemic immune-inflammation index is an independent predictor of survival for metastatic colorectal cancer and its association with the lymphocytic response to the tumor.

BACKGROUND: Systemic inflammation and immune dysfunction has been proved to be significantly associated with cancer progression and metastasis in many cancer types, including colorectal cancer. We examined the prognostic significance of the systemic immune-inflammation index (SII) in patients with metastatic colorectal cancer (mCRC) and the relationship between the lymphocytic response to the tumor and this index. METHODS: This retrospective study evaluated 240 consecutive patients with newly diagnosed stage IV mCRC who underwent surgical resection. The SII values were calculated based on preoperative laboratory data regarding platelet, neutrophil, and lymphocyte counts. Tumor-infiltrating lymphocytes were evaluated using the surgical specimens. The overall survival and their 95% confidence interval (95% CI) were estimated by regression analyses and the Kaplan-Meier method. RESULTS: After a mean follow-up of 26.7 (1.1-92.4) months, 146 patients (60.8%) died. In the univariate analysis, a high SII was significantly associated with poor overall survival (P = 0.009). The multivariable analysis also confirmed that a high SII was independently associated with poor overall survival (hazard ratio: 1.462, 95% confidence interval 1.049-2.038, P = 0.025). The SII value was significantly correlated with the TILs value at the tumor's center (P = 0.04), but not at the invasive margin (P = 0.39). When we evaluated overall survival for groupings of the tumor-infiltrating lymphocytes and SII values, we identified three distinct prognostic groups. The group with low tumor-infiltrating lymphocyte values and high SII values had the worst prognosis. CONCLUSIONS: A high SII value independently predicts poor clinical outcomes among patients with mCRC. In addition, combining the lymphocytic response to the tumor and SII could further enhance prognostication for mCRC.

Circulating hematopoietic stem and progenitor cells are myeloid-biased in cancer patients.

Cancer is associated with a profound perturbation in myelopoiesis that results in the accumulation of myeloid-derived suppressor cells (MDSCs) to promote disease progression. Recent studies in mice suggest that tumor-derived factors could regulate the differentiation of hematopoietic stem and progenitor cells (HSPCs) in the bone marrow and subsequently contribute to dysregulation of hematopoiesis. However, the nature and role of HPSCs in patients with cancer remain unknown. Here we show, in detailed studies of the peripheral blood from 133 untreated patients with seven different types of tumors, that the composition of circulating HSPCs was significantly altered in patients with solid tumors. The frequencies of circulating granulocyte-monocyte progenitors (GMPs) were increased four to seven fold in all types of tumors examined, and the circulating hematopoietic precursors exhibited myeloid bias with a skew toward granulocytic differentiation in patients with solid tumors. These myeloid precursors are selectively enriched in tumor tissues, and the high levels of circulating GMPs were positively correlated with disease progression. By using cord blood-derived CD34(+) cells, we developed an in vitro short-term culture model to effectively induce the rapid generation of MDSCs. We found that, among the factors produced by various tumors, GM-CSF, granulocyte colony-stimulating factor, and IL-6 could not only promote the myeloid-biased differentiation, but also induce the differentiation of myeloid precursors into functional MDSCs. These findings suggest that the altered circulating HSPCs may serve as an important link between dysregulated bone marrow hematopoiesis and accumulated MDSCs in patients with cancer.

[Clinical monitoring of myocardial injury in neonates with intrauterine distress].

OBJECTIVE: To investigate whether no asphyxia neonates with intrauterine distress are complicated with myocardial injury and determine the sensitive biochemical diagnostic parameters. METHODS: A total of 89 neonates born in the First Affiliated Hospital of Sun Yat-sen University from July 2009 to December 2009 were enrolled. Fifty-three fetal distress cases with Apgar score > 7 at 1 and 5 minutes were enrolled in the study group; while the rest 36 healthy neonates, whose Apgar score = 10 at 1 and 5 minutes, were the control group. Umbilical artery blood samples of all cases were collected for blood gas analysis and biochemical measurement. RESULTS: (1) pH (7.23 ± 0.07) and BE [(-4.8 ± 3.0) mmol/L] in the study group were significantly lower than pH (7.31 ± 0.03) and BE [(-2.1 ± 1.5) mmol/L ] in the control group(P < 0.05). The lactic acid of study group [(5.2 ± 2.3) mmol/L] was higher than that of the control group [(2.3 ± 1.1) mmol/L], and the difference was significant (P < 0.01). However, there was no significant difference between the two groups in PaO2 [(16.2 ± 7.9) mm Hg (1 mm Hg = 0.133 kPa) vs. (17.5 ± 6.7) mm Hg] and PaCO2 [(54.0 ± 11.2) mm Hg vs. (48.5 ± 5.4) mm Hg; P > 0.05]. (2) The level of CK-MB in neonates with fetal distress[ (48 ± 59) U/L] was significantly higher than that of healthy neonates [(36 ± 27) U/L]. However, no significant difference was found in CK [(194 ± 73) U/L vs. (162 ± 95) U/L] and BNP levels [(519 ± 309) ng/L vs. (481 ± 216) ng/L; P > 0.05]. (3) Spearman rank correlation analysis showed that CK-MB level was negatively correlated with pH (r = -0.296, P < 0.05) and BE (r = -0.318, P < 0.05) of umbilical artery blood, while BNP level was positively correlated with umbilical lactic acid (r = 0.278, P < 0.05). No correlation was found between other parameters (P > 0.05). CONCLUSIONS: Intrauterine distress without neonatal asphyxia had effect on fetal myocardial injury. CK-MB can be used as a sensitive parameter for monitoring the development of myocardial injury. The severity of myocardial injury was related to fetal acidosis.

Establishment of an evaluation model for human milk fat substitutes.

Fatty acid composition and distribution of human milk fat (HMF), from mothers over different lactating periods in Guangzhou, China, were analyzed. The universal characteristics were consistent with previously reported results although the fatty acid content was within a different range and dependent on the local population (low saturated fatty acid and high oleic acid for Guangdong mothers' milk fat). Based on the composition of the total and sn-2 fatty acids of mature milk fat, an efficient evaluation model was innovatively established by adopting the "deducting score" principle. The model showed good agreement between the scores and the degree of similarity by assessing 15 samples from different sources including four samples of HMF, eight samples of human milk fat substitutes (HMFSs) and infant formulas, and three samples of fats and oils. This study would allow for the devolvement of individual human milk fat substitutes with different and specific fatty acid compositions for local infants.

[Pregnant outcomes and neonatal anthropometry in women with abnormal glucose challenge test and normal oral glucose tolerance test during pregnancy.].

OBJECTIVE: To evaluate the influences of abnormal glucose challenge test(GCT) on pregnancy outcomes and neonatal anthropometric data in women with normal oral glucose tolerance test(OGTT). METHODS: Totally 214 women who delivered in the First Affiliated Hospital of Sun Yat-sen University from November 2006 to December 2007 were enrolled. 50 g GCT was performed at 24-28 weeks of gestation and 75 g OGTT would be followed if GCT >/= 7.8 mmol/L. Those patients, whose OGTT results below the following criteria (5.3 mmol/L, 10.0 mmol/L, 8.6 mmol/L, 7.8 mmol/L), were classified as normal OGTT. Altogether, 116 of the 214 women with abnormal GCT and normal OGTT were collected as the study group and the rest 98 women with normal GCT as the control group. The pregnant outcomes of the two groups were analyzed. The neonatal anthropometry, including birth weight, body length, head circumference and shoulder circumference, were recorded. Other neonatal anthropometric data, such as upper arm circumference, tricep skinfold thickness and hypodermic fat thickness of abdomen were measured by a tape measure within 24 hours after birth. RESULTS: (1) Pregnant outcomes: No significant difference was found in the rate of assisted vaginal delivery, polyhydramnios, premature rupture of membranes and fetal distress between the study and control group [10.3% (12/116) vs 4% (4/98), 5.2% (6/116) vs 10% (10/98), 13.8% (16/116) vs 17% (17/98), 20.7% (24/116) vs 13% (13/98), P > 0.05, respectively], but the rate of cesarean section, spontaneous vaginal delivery and large for gestational age babies in the study group were different from those of the control [72.4% (84/116) vs 51% (51/98), 17.2% (20/116) vs 45% (44/98), 25.9% (30/116) vs 6% (6/98), P < 0.05, respectively]. (2) Neonatal anthropometry: The birth weight of the study group was significantly higher than that of the control group [(3.4 +/- 0.4) kg vs (3.3 +/- 0.4) kg, P < 0.05], but no significant difference was shown in any other neonatal anthropometric results between the study and control group, including body length [(49.9 +/- 1.3) cm vs (49.7 +/- 1.4) cm], head circumference [(33.4 +/- 1.5) cm vs (33.8 +/- 1.7) cm], shoulder circumference [(35.4 +/- 2.3) cm vs (35.0 +/- 2.3) cm], upper arm circumference [(11.0 +/- 0.7) cm vs (10.9 +/- 0.8) cm], tricep skinfold thickness [(9.7 +/- 1.0) mm vs (9.9 +/- 1.4) mm] and hypodermic fat thickness of abdomen [(7.2 +/- 1.2) mm vs (7.2 +/- 1.0) mm; all P > 0.05]. CONCLUSION: Women with abnormal GCT alone may have no significant influences on neonatal anthropometric data, but might have more cesarean section, large for gestational age babies, and neonatal birth weight than those women with normal GCT.