Mesenteric Castleman Disease Mimicking Neuroendocrine Tumor.

Castleman disease (CD) is a benign lymphoproliferative disorder of unknown etiology, which can involve any part of the body. CD can involve a single lymph node (unicentric) or multiple lymph nodes (multicentric) of which unicentric CD is the most common type. The unicentric CD is usually localized, asymptomatic, and often appears as an incidental mass on radiographs, whereas multicentric CD is characterized by systemic involvement. Mesenteric involvement of CD is very rare. In this article, we present a case of the unicentric CD of small bowel mesentery, which mimicked a neuroendocrine tumor preoperatively.

Mesenteric lymph nodes: a critical site for the up-regulatory effect of hUC-MSCs on Treg cells by producing TGF-ß1 in colitis treatment.

BACKGROUND: Mesenchymal stem cells (MSCs) demonstrate a wide range of therapeutic capabilities in the treatment of inflammatory bowel disease (IBD). The intraperitoneal injection of MSCs has exhibited superior therapeutic efficacy on IBD than intravenous injection. Nevertheless, the precise in vivo distribution of MSCs and their biological consequences following intraperitoneal injection remain inadequately understood. Additional studies are required to explore the correlation between MSCs distribution and their biological effects. METHODS: First, the distribution of human umbilical cord MSCs (hUC-MSCs) and the numbers of Treg and Th17 cells in mesenteric lymph nodes (MLNs) were analyzed after intraperitoneal injection of hUC-MSCs. Subsequently, the investigation focused on the levels of transforming growth factor beta1 (TGF-ß1), a key cytokine to the biology of both Treg and Th17 cells, in tissues of mice with colitis, particularly in MLNs. The study also delved into the impact of hUC-MSCs therapy on Treg cell counts in MLNs, as well as the consequence of TGFB1 knockdown hUC-MSCs on the differentiation of Treg cells and the treatment of IBD. RESULTS: The therapeutic effectiveness of intraperitoneally administered hUC-MSCs in the treatment of colitis was found to be significant, which was closely related to their quick migration to MLNs and secretion of TGF-ß1. The abundance of hUC-MSCs in MLNs of colitis mice is much higher than that in other organs even the inflamed sites of colon. Intraperitoneal injection of hUC-MSCs led to a significant increase in the number of Treg cells and a decrease in Th17 cells especially in MLNs. Furthermore, the concentration of TGF-ß1, the key cytokine for Treg differentiation, were also found to be significantly elevated in MLNs after hUC-MSCs treatment. Knockdown of TGFB1 in hUC-MSCs resulted in a noticeable reduction of Treg cells in MLNs and the eventually failure of hUC-MSCs therapy in colitis. CONCLUSIONS: MLNs may be a critical site for the regulatory effect of hUC-MSCs on Treg/Th17 cells and the therapeutic effect on colitis. TGF-ß1 derived from hUC-MSCs promotes local Treg differentiation in MLNs. This study will provide new ideas for the development of MSC-based therapeutic strategies in IBD patients.

Effects of the commensal microbiota on spleen and mesenteric lymph node immune function: investigation in a germ-free piglet model.

Commensal microbial-host interaction is crucial for host metabolism, growth, development, and immunity. However, research on microbial-host immunity in large animal models has been limited. This study was conducted to investigate the effects of the commensal microbiota on immune function in two model groups: germ-free (GF) and specific-pathogen-free (SPF) piglets. The weight and organ index of the spleen of the GF piglet were larger than those in the SPF piglet (P < 0.05). The histological structure of the red pulp area and mean area of germinal centers were larger in the SPF piglet than in the GF piglet (P < 0.05), whereas the areas of staining of B cells and T cells in the spleen and mesenteric lymph nodes (MLNs) were lower in the GF piglet (P < 0.05). We identified immune-related genes in the spleen and MLNs using RNA sequencing, and used real-time quantitative PCR to analyze the expression of core genes identified in gene set enrichment analysis. The expression levels of genes in the transforming growth factor-ß/SMAD3 signaling pathway, Toll-like receptor 2/MyD88/nuclear factor-κB signaling pathway, and pro-inflammatory factor genes IL-6 and TNF-α in the spleen and MLNs were higher in the SPF piglet and in splenic lymphocytes compared with those in the GF and control group, respectively, under treatment with acetic acid, propionic acid, butyric acid, lipopolysaccharide (LPS), or concanavalin A (ConA). The abundances of plasma cells, CD8++ T cells, follicular helper T cells, and resting natural killer cells in the spleen and MLNs were significantly greater in the SPF piglet than in the GF piglet (P < 0.05). In conclusion, the commensal microbiota influenced the immune tissue structure, abundances of immune cells, and expression of immune-related pathways, indicating the importance of the commensal microbiota for spleen and MLNs development and function. In our study, GF piglet was used as the research model, eliminating the interference of microbiota in the experiment, and providing a suitable and efficient large animal research model for exploring the mechanism of "microbial-host" interactions.

Enhanced Proteomic Coverage in Tissue Microenvironment by Immune Cell Subtype Library-Assisted DIA-MS.

Immune cells that infiltrate the tumor microenvironment (TME) play crucial roles in shaping cancer development and influencing clinical outcomes and therapeutic responses. However, obtaining a comprehensive proteomic snapshot of tumor-infiltrating immunity in clinical specimens is often hindered by small sample amounts and a low proportion of immune infiltrating cells in the TME. To enable in-depth and highly sensitive profiling of microscale tissues, we established an immune cell-enriched library-assisted strategy for data-independent acquisition mass spectrometry (DIA-MS). Firstly, six immune cell subtype-specific spectral libraries were established from sorted cluster of differentiation markers, CD8+, CD4+ T lymphocytes, B lymphocytes, natural killer cells, dendritic cells, and macrophages in murine mesenteric lymph nodes (MLNs), covering 7815 protein groups with surface markers and immune cell-enriched proteins. The feasibility of microscale immune proteomic profiling was demonstrated on 1 µg tissue protein from the tumor of murine colorectal cancer (CRC) models using single-shot DIA; the immune cell-enriched library increased coverage to quantify 7419 proteins compared to directDIA analysis (6978 proteins). The enhancement enabled the mapping of 841 immune function-related proteins and exclusive identification of many low-abundance immune proteins, such as CD1D1, and CD244, demonstrating high sensitivity for immune landscape profiling. This approach was used to characterize the MLNs in CRC models, aiming to elucidate the mechanism underlying their involvement in cancer development within the TME. Even with a low percentage of immune cell infiltration (0.25-3%) in the tumor, our results illuminate downregulation in the adaptive immune signaling pathways (such as C-type lectin receptor signaling, and chemokine signaling), T cell receptor signaling, and Th1/Th2/Th17 cell differentiation, suggesting an immunosuppressive status in MLNs of CRC model. The DIA approach using the immune cell-enriched libraries showcased deep coverage and high sensitivity that can facilitate illumination of the immune proteomic landscape for microscale samples.

Lymphatic Uptake of a Highly Lipophilic Protease Inhibitor Prodrug from a Lipid-Based Formulation is Limited by Instability in the Intestine.

Dabigatran etexilate (DABE) is a lipophilic double alkyl ester prodrug of dabigatran (DAB) which is a serine protease inhibitor used clinically as an anticoagulant. Recently, translocation of serine protease enzymes, including trypsin, from the gut into the mesenteric lymph and then blood has been associated with organ failure in acute and critical illnesses (ACIs). Delivery of DABE into mesenteric lymph may thus be an effective strategy to prevent organ failure in ACIs. Most drugs access the mesenteric lymph in low quantities following oral administration, as they are rapidly transported away from the intestine via the blood. Here, we examine the potential to deliver DABE into the mesenteric lymph by promoting association with lymph lipid transport pathways via co-administration with a lipid-based formulation (LBF). A series of self-emulsifying LBFs were designed and tested in vitro for their potential to form stable DABE loaded emulsions and keep DABE solubilised and stable over time in simulated gastrointestinal conditions. The LBFs were found to form fine emulsions with a droplet size of 214 ± 30 nm and DABE was stable in the formulation. The stability of DABE in vitro in simulated intestinal conditions, plasma and lymph samples was also evaluated to ensure stability in collected samples and to evaluate whether the prodrug is likely to release active DAB. Ultimately, a highly uniform and stable self-emulsifying Type III A LBF of DABE was chosen for progression into in vivo studies in male Sprague Dawley rats to confirm the lymphatic uptake and plasma pharmacokinetics. Both in vitro and in vivo in plasma and lymph, DABE was rapidly converted to an intermediate and DAB. The main species present in vivo in both plasma and lymph was DAB and mass transport of DABE and DAB in lymph was minimal (∼0.5 % of dose). Importantly, the concentration of DABE in lymph was substantially (20-176 fold) higher than in plasma, supporting that if the prodrug were stable and did not convert to DAB in the intestine, it would be lymphatically transported. Future studies will therefore focus on optimizing the design of the prodrug and formulation to improve stability during absorption and further promote lymphatic uptake.

Effect of feeding fermented distiller's grains diets on immune status and metabolomics of spleen and mesenteric lymph nodes in finishing cattle.

To explore the effect of feeding fermented distiller's grains (FDG) diets on spleen and mesenteric lymph nodes (MLN) immune status and metabolomics in finishing cattle, eighteen Guanling crossbred cattle (18 months old, 250.0 ± 25 kg) were randomly divided into 3 groups: a basal diet (Control) group, an FDG-15% group, and an FDG-30% group (containing 0%, 15% and 30% FDG to partially replace the concentrates, respectively). After 75 days, the spleens and MLN were collected for detection of relative spleen weight, immune parameters, and metabolomic analysis. Compared with the Control group, FDG-30% group significantly increased (P<0.05) the relative spleen weight. In addition, the level of IL-17A in the spleen of the FDG-30% group was significantly higher than that of the FDG-15% group. Metabolomic analysis showed that differential metabolites (VIP＞1, P＜0.05) of spleen and MLN in FDG-15% and FDG-30% groups are mostly lipids and lipid molecules. KEGG analysis illustrated that choline metabolism in cancer, glycerophospholipid metabolism, biosynthesis of unsaturated fatty acids and insulin resistance were metabolic pathways in spleen shared by FDG-15% group vs.Control group and FDG-30% group vs.Control group, and choline metabolism in cancer was a metabolic pathway in MLN shared by FDG-15% group vs.Control group and FDG-30% group vs.Control group. These results suggest that feeding FDG may promote spleen development by regulating choline metabolism in cancer, glycerophospholipid metabolism, biosynthesis of unsaturated fatty acids and insulin resistance. Additionally, it may affect MLN development by regulating choline metabolism in cancer. SIGNIFICANCE: Fermented distiller's grains (FDG) is a high quality alternative to feed because it is rich in beneficial microorganisms and nutrients. The spleen and mesenteric lymph nodes (MLN) are important peripheral immune organs in animals, whose status reflects the health of the animal. However, there are few reports on the effect of feeding FDG diets on spleen and MLN immune status and metabolomics in domestic animals. In this study, we found that feeding FDG may promote spleen development by regulating choline metabolism in cancer, glycerophospholipid metabolism, biosynthesis of unsaturated fatty acids and insulin resistance metabolic pathways, and may affect MLN development by regulating choline metabolism in cancer. This study extends our understanding of the metabolomics of the spleen and MLN in FDG and helps to further understand of the immunomodulatory effects of the FDG diet.

Unilateral gluteal myositis as a unique presentation in mesenteric Kikuchi-Fujimoto disease.

Kikuchi-Fujimoto disease (KFD) is a self-limiting disease, characterised by fever and cervical lymphadenopathy. Lymphadenopathy without cervical lymph node involvement is rare and may mimic lymphoma. Although KFD can be associated with extranodal involvement, muscle involvement has not been reported. Herein, we report a novel case of unilateral gluteal myositis associated with mesenteric KFD in a patient who presented with persistent fever and right hip pain. Radiological imaging revealed an inflammatory lesion on the right gluteal muscle and multiple enlarged abdominal lymph nodes. No cervical lymphadenopathy was observed. A mesenteric lymph node biopsy was performed, and the histopathological findings led to a diagnosis of KFD. By day 29, the patient's body temperature gradually returned to normal without any therapeutic intervention. Follow-up radiological imaging showed resolution of the gluteal lesion and a significant decrease in abdominal lymph node size. Considering the clinical course, the unilateral myositis may have developed as an extranodal involvement of KFD. Even if the clinical findings appear unrelated to those of KFD, a differential diagnosis that includes KFD should be considered in patients with unknown origin of fever.

Distribution of lamivudine into lymph node HIV reservoir.

Efficient delivery of antiretroviral agents to lymph nodes is important to decrease the size of the HIV reservoir within the lymphatic system. Lamivudine (3TC) is used in first-line regimens for the treatment of HIV. As a highly hydrophilic small molecule, 3TC is not predicted to associate with chylomicrons and therefore should have negligible uptake into intestinal lymphatics following oral administration. Similarly, negligible amounts of 3TC are predicted to be transported into peripheral lymphatics following subcutaneous (SC) injection due to the faster flow rate of blood in comparison to lymph. In this work, we performed pharmacokinetic and biodistribution studies of 3TC in rats following oral lipid-based, oral lipid-free, SC, and intravenous (IV) administrations. In the oral administration studies, mesenteric lymph nodes (MLNs) had significantly higher 3TC concentrations compared to other lymph nodes, with mean tissue:serum ratios ranging from 1.4 to 2.9. However, cells and chylomicrons found in mesenteric lymph showed low-to-undetectable concentrations. In SC studies, administration-side (right) draining inguinal and popliteal lymph nodes had significantly higher concentrations (tissue:serum ratios as high as 3.2) than corresponding left-side nodes. In IV studies, lymph nodes had lower mean tissue:serum ratios ranging from 0.9 to 1.4. We hypothesize that following oral or SC administration, slower permeation of this hydrophilic molecule into blood capillaries may result in considerable passive 3TC penetration into lymphatic vessels. Further studies will be needed to clarify the mechanism of delivery of 3TC and similar antiretroviral drugs into the lymph nodes.

Development of lipophilic ester prodrugs of dolutegravir for intestinal lymphatic transport.

The establishment of latent cellular and anatomical viral reservoirs is a major obstacle to achieving a cure for people infected by HIV. Mesenteric lymph nodes (MLNs) are one of the most important anatomical reservoirs of HIV. Suboptimal levels of antiretroviral (ARVs) drugs in these difficult-to-penetrate viral reservoirs is one of the limitations of current antiretroviral therapy (ART) regimens. This study aimed to design and assess highly lipophilic ester prodrugs of dolutegravir (DTG) formulated with long-chain triglyceride (LCT) for delivery of DTG to the viral reservoir in mesenteric lymph and MLNs. A number of alkyl ester prodrugs of DTG were designed based on the predicted affinity to chylomicrons (CM), and the six most promising prodrugs were selected and synthesised. The synthesised prodrugs were further assessed for their intestinal lymphatic transport potential and biotransformation in biorelevant media in vitro and ex vivo. DTG and the most promising prodrug (prodrug 5) were then assessed in pharmacokinetic and biodistribution studies in rats. Although oral administration of 5 mg/kg of unmodified DTG (an allometrically scaled dose from humans) with or without lipids achieved concentrations above protein binding-adjusted IC90 (PA-IC90) (64 ng/mL) in most tissues, the drug was not selectively targeted to MLNs. The combination of lipophilic ester prodrug and LCT-based formulation approach improved the targeting selectivity of DTG to MLNs 4.8-fold compared to unmodified DTG. However, systemic exposure to DTG was limited, most likely due to poor intestinal absorption of the prodrug following oral administration. In vitro lipolysis showed a good correlation between micellar solubilisation of the prodrug and systemic exposure to DTG in rats in vivo. Thus, it is prudent to include in vitro lipolysis in the early assessment of orally administered drugs and prodrugs in lipidic formulations, even when intestinal lymphatic transport is involved in the absorption pathway. Further studies are needed to clarify the underlying mechanisms of low systemic bioavailability of DTG following oral administration of the prodrug and potential ways to overcome this limitation.

Effects of rumen cannulation combined with different pre-weaning feeding intensities on the intestinal, splenic and thymic immune system in heifer calves several month after surgery.

Fistulation is a helpful procedure in animal nutritional research and also common practise in human medicine. However, there are indications that alterations in the upper gastrointestinal tract contribute to intestinal immune modulations. The present study aimed to investigate effects of a rumen cannulation in week 3 of life on the intestinal and tissue specific immune system of 34-week old heifers. Nutrition influences the development of the neonatal intestinal immune system to a high extent. Therefore, rumen cannulation was investigated in combination with different pre-weaning milk feeding intensities (20% (20MR) vs. 10% milk replacer feeding (10MR). Heifers of 20MR without rumen cannula (NRC) showed higher cluster of differentiation (CD)8+ T cell subsets in mesenteric lymph nodes (MSL) compared to heifers with rumen cannula (RC) and 10MRNRC heifers. CD4+ T cell subsets in jejunal intraepithelial lymphocytes (IELs) were higher in 10MRNRC heifers compared to 10MRRC heifers. CD4+ T cell subsets in ileal IELs were lower and CD21+ B cell subsets were higher in NRC heifers compared to RC heifers. CD8+ T cell subsets in spleen tended to be lower in 20MRNRC heifers compared to all other groups. Splenic CD21+ B cell subsets were higher in 20MRNRC heifers compared to RC heifers. Splenic toll like receptor (TLR) 6 expression was increased and IL4 expression tended to be increased in RC heifers than NRC heifers. Splenic TLR2, 3 and 10 gene expression was higher in 20MR compared to 10MR heifers. Jejunal prostaglandin endoperoxide synthase 2 expression was higher in RC heifers than NRC heifers, and MUC2 expression tended to increase in 20MR heifers compared to 10MR heifers. In conclusion, rumen cannulation modulated T and B cell subsets in the down streaming gastrointestinal tract and spleen. Pre-weaning feeding intensity seemed to affect intestinal mucin secretion and T and B cell subsets in MSL, spleen and thymus until several month later. Interestingly, in MSL, spleen and thymus the 10MR feeding regime evoked similar modulations of T and B cell subsets like rumen cannulation.

Excision of mesenteric lymph nodes alters gut microbiota and impairs social dominance in adult mice.

INTRODUCTION: Mesenteric lymph nodes (MLNs) are central in immune anatomy. MLNs are associated with the composition of gut microbiota, affecting the central system and immune system. Gut microbiota was found to differ among individuals of different social hierarchies. Nowadays, excision of MLNs is more frequently involved in gastrointestinal surgery; however, the potential side effects of excision of MLNs on social dominance are still unknown. METHODS: MLNs were removed from male mice (7-8 weeks old). Four weeks after MLN removal, social dominance test was performed to investigate social dominance; hippocampal and serum interleukin (IL)-1ß, IL-10, and tumor necrosis factor-alpha (TNF-α) were investigated; and histopathology was used to evaluate local inflammation of the ileum. The composition of the gut microbiota was then examined to understand the possible mechanism, and finally intraperitoneal injection of IL-10 was used to validate the effect of IL-10 on social dominance. RESULTS: There was a decrease in social dominance in the operation group compared to the control group, as well as a decrease in serum and hippocampal IL-10 levels, but no difference in serum and hippocampal IL-1ß and TNF-α levels, and no local inflammation of the ileum after MLN removal. 16S rRNA sequencing analysis showed that the relative abundance of the class Clostridia was decreased in the operation group. This decrease was positively associated with serum IL-10 levels. Furthermore, intraperitoneal injection of IL-10 in a subset of mice increased social dominance. CONCLUSIONS: Our findings suggested that MLNs contributed to maintaining social dominance, which might be associated with reduced IL-10 and the imbalance of specific flora in gut microbiota.

Gut dysbiosis promotes the breakdown of oral tolerance mediated through dysfunction of mucosal dendritic cells.

While dysbiosis in the gut is implicated in the impaired induction of oral tolerance generated in mesenteric lymph nodes (MesLNs), how dysbiosis affects this process remains unclear. Here, we describe that antibiotic-driven gut dysbiosis causes the dysfunction of CD11c+CD103+ conventional dendritic cells (cDCs) in MesLNs, preventing the establishment of oral tolerance. Deficiency of CD11c+CD103+ cDCs abrogates the generation of regulatory T cells in MesLNs to establish oral tolerance. Antibiotic treatment triggers the intestinal dysbiosis linked to the impaired generation of colony-stimulating factor 2 (Csf2)-producing group 3 innate lymphoid cells (ILC3s) for regulating the tolerogenesis of CD11c+CD103+ cDCs and the reduced expression of tumor necrosis factor (TNF)-like ligand 1A (TL1A) on CD11c+CD103+ cDCs for generating Csf2-producing ILC3s. Thus, antibiotic-driven intestinal dysbiosis leads to the breakdown of crosstalk between CD11c+CD103+ cDCs and ILC3s for maintaining the tolerogenesis of CD11c+CD103+ cDCs in MesLNs, responsible for the failed establishment of oral tolerance.

Characteristics of Th9 cells in Schistosoma japonicum-infected C57BL/6 mouse mesenteric lymph node.

Interleukin 9 (IL-9) is an effective cytokine secreted by newly defined Th9 cells, which is involved in allergic and infectious diseases. In this study, lymphocytes were isolated from mesenteric lymph node (MLN), spleen, liver, lung, and Peyer's patches (PP) of C57BL/6 mice 5-6 weeks after S. japonicum infection, intracellular cytokine staining was done to detect the percentage of IL-9-producing CD4+ T cells. The qPCR and ELISA were used to verify the content of IL-9 in MLN. The population of IL-9-producing lymphocyte subset was identified by FACS. In addition, the dynamic changes and cytokine profiles of Th9 cells in the MLN of infected mice were detected by FACS. ELISA was used to detect IL-9 induced by soluble egg antigen (SEA) from isolated lymphocytes in mouse MLN. The results showed that the percentage of IL-9-secreting Th9 cells in the MLN of the infected mouse was higher than that in the spleen, liver, lung, or PP. Though CD8+ Tc cells, NKT cells, and γδT cells could secrete IL-9, CD4+ Th cells were the main source of IL-9 in S. japonicum-infected C57BL/6 mice (P < 0.05). The percentage of Th9 cells in MLN of infected mouse increased from week 3-4, and reached a peak at week 5-6, then began to decrease from week 7-8 (P < 0.05). Moreover, Th9 cells could also secrete a small amount of IL-4, IFN-γ, IL-5, and IL-10. Our results suggested a higher percentage of Th9 cells was induced in the MLN of S. japonicum-infected mice, which might play an important role in the early stage of S. japonicum-induced disease.

EXPERIMENTAL GESTATIONAL DIABETES DISRUPTS THE FORMATION OF IMMUNE TOLERANCE IN OFFSPRING.

OBJECTIVE: The aim: To analyze the mRNA gene expression level of Aire, Deaf1, Foxp3, Ctla4, Il10, Nlrp3 and distribution of NLRP3+-cells in mesenteric lymph nodes (MLNs) of the offspring of rats with GD, both untreated and treated with glibenclamide and in conditions of insulin oral tolerance formation. PATIENTS AND METHODS: Materials and methods: The study involves 160 male rats, one- or six-month-old. The mRNA genes expression was studied by real time quantitative poly¬merase chain reaction. Structure of Nlrp3+ -cells population was studied by histological sections of MLNs. RESULTS: Results: We observed AIRE gene repression, reduced mRNA levels of Deaf1 and the transcription factor Foxp3 in offspring of rats with GD. This was accompanied by inhibition of IL-10 gene expression and negative costimulatory molecules Ctla4. The development of the experimental GD was accompanied by transcrip¬tional induction of the Nlrp3 gene in MLNs of descendants. The administration of glibenclamide to pregnant female rats with GD inhibited the transcription of the Nlrp3 gene only in one-month-old offspring (5.3-fold) and did not change it in six-month-old animals. In offspring of rats with GD, the density of the NLRP3+-lymphocyte population in the MLNs increased, more pronounced in one-month-old animals. The administration of glibenclamide to pregnant rats with GD reduced the number of NLRP3+ -lymphocytes only in one-month-old offspring (by 33.0 %), whereas this index in six month-old offspring even increased. CONCLUSION: Conclusions: Experimental prenatal hyperglycemia leads to increased proinflammatory signaling and violation of peripheral immunological tolerance formation more pronounced at one month of life.

Fecal and Tissue Microbiota Are Associated with Tumor T-Cell Infiltration and Mesenteric Lymph Node Involvement in Colorectal Cancer.

Colorectal cancer (CRC) is associated with alterations of the fecal and tissue-associated microbiome. Preclinical models support a pathogenic role of the microbiome in CRC, including in promoting metastasis and modulating antitumor immune responses. To investigate whether the microbiome is associated with lymph node metastasis and T cell infiltration in human CRC, we performed 16S rRNA gene sequencing of feces, tumor core, tumor surface, and healthy adjacent tissue collected from 34 CRC patients undergoing surgery (28 fecal samples and 39 tissue samples). Tissue microbiome profiles-including increased Fusobacterium-were significantly associated with mesenteric lymph node (MLN) involvement. Fecal microbes were also associated with MLN involvement and accurately classified CRC patients into those with or without MLN involvement. Tumor T cell infiltration was assessed by immunohistochemical staining of CD3 and CD8 in tumor tissue sections. Tumor core microbiota, including members of the Blautia and Faecalibacterium genera, were significantly associated with tumor T cell infiltration. Abundance of specific fecal microbes including a member of the Roseburia genus predicted high vs. low total and cytotoxic T cell infiltration in random forests classifiers. These findings support a link between the microbiome and antitumor immune responses that may influence prognosis of locally advanced CRC.

N-Acetylcysteine Administration Improves the Redox and Functional Gene Expression Levels in Spleen, Mesenteric Lymph Node and Gastrocnemius Muscle in Piglets Infected with Porcine Epidemic Diarrhea Virus.

Our previous study reported that N-acetylcysteine (NAC) administration improved the function of intestinal absorption in piglets infected with porcine epidemic diarrhea virus (PEDV). However, the effects of NAC administration on the functions of other tissues and organs in PEDV-infected piglets have not been reported. In this study, the effects of NAC on the liver, spleen, lung, lymph node, and gastrocnemius muscle in PEDV-infected piglets were investigated. Thirty-two 7-day-old piglets with similar body weights were randomly divided into one of four groups: Control group, NAC group, PEDV group, and PEDV+NAC group (eight replicates per group and one pig per replicate). The trial had a 2 × 2 factorial design consisting of oral administration of 0 or 25 mg/kg body weight NAC and oral administration of 0 or 1.0 × 104.5 TCID50 PEDV. The trial lasted 12 days. All piglets were fed a milk replacer. On days 5-9 of the trial, piglets in the NAC and PEDV + NAC groups were orally administered NAC once a day; piglets in the control and PEDV groups were orally administered the same volume of saline. On day 9 of trial, piglets in the PEDV and PEDV+NAC groups were orally administrated 1.0 × 104.5 TCID50 PEDV, and the piglets in the control and NAC groups were orally administrated the same volume of saline. On day 12 of trial, samples, including of the liver, spleen, lung, lymph node, and gastrocnemius muscle, were collected. PEDV infection significantly increased catalase activity but significantly decreased the mRNA levels of Keap1, Nrf2, HMOX2, IFN-α, MX1, IL-10, TNF-α, S100A12, MMP3, MMP13, TGF-ß, and GJA1 in the spleens of piglets. NAC administration ameliorated abnormal changes in measured variables in the spleens of PEDV-infected piglets. In addition, NAC administration also enhanced the antioxidant capacity of the mesenteric lymph nodes and gastrocnemius muscles in PEDV-infected piglets. Collectively, these novel results revealed that NAC administration improved the redox and functional gene expression levels in the spleen, mesenteric lymph nodes, and gastrocnemius muscle in PEDV-infected piglets.

Is complete mesocolic excision or total mesorectal excision necessary during cytoreductive surgery in ovarian peritoneal carcinomatosis with colonic involvement?

INTRODUCTION: Cytoreductive surgery (CRS) and intraperitoneal chemotherapy are effective in the treatment of ovarian peritoneal carcinomatosis (OPC). Colon resection is often required to achieve maximal cytoreduction during CRS. The success of complete mesocolic excision (CME) and total mesorectal excision (TME) in the surgical treatment of primary colorectal tumors is well-known. Our study aimed to investigate the factors affecting mesocolic lymph node metastasis (MLNM) and the contribution of CME/TME techniques to maximal cytoreduction in patients diagnosed with ovarian peritoneal carcinomatosis (OPC) with colon metastasis. PATIENTS AND METHODS: Between 2004-2020, 30 patients who underwent colorectal resection with CME/TME techniques due to OPC-related colon metastasis were retrospectively analyzed. RESULTS: The median age of patients was 61 (33-86). Six (20%) patients underwent total colectomy, 7 (23%) subtotal colectomy, 6 (20%) right hemicolectomy, 4 (13%) left hemicolectomy, and 7 (23%) rectosigmoid resection. Histopathological diagnosis was high-grade serous carcinoma in 29 (97%) patients, and malignant mixed Mullerian tumor in 1 (3%) patient. MLNM was detected in 17 (56%) of 30 patients. There was a significant relationship between MLNM and pelvic and para-aortic lymph node metastasis (PALNM) (p = 0.009) and lymphovascular invasion in primary ovarian tumors (p = 0.017). There was no significant relationship between MLNM and depth of colonic invasion (p = 0.463), histological grade (p = 0.711), and primary/secondary surgery (p = 0.638). MLNM was seen in 8 (47%) of 17 patients with only serosal invasion. CONCLUSION: A high rate of MLNM can be seen in OPC-induced colon metastasis regardless of the degree of colon wall invasion. In patients with PALNM, the frequency of MLNM increases. We believe that if colon resection is to be performed in OPC, a colectomy should be performed by CME/TME principles to achieve maximal cytoreduction.

Omega-3 polyunsaturated fatty acids alleviates lung injury mediated by post-hemorrhagic shock mesenteric lymph.

Severe hemorrhage-induced acute lung injury (ALI) remains the major contributor to critical patient mortality and is associated with posthemorrhagic shock mesenteric lymph (PHSML) return. Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) play overall protection on acute hemorrhage, but a reliable mechanism needs to be identified. The aims of this study were to investigate the role of ω-3 PUFAs in alleviating ALI and whether is related to the endotoxin contained in PHSML. Mesenteric lymph was harvested from rats subjected to hemorrhagic shock (hemorrhage-induced hypotension of 40 ± 2 mmHg for 90 min plus by resuscitation) or sham shock. The effect of ω-3 PUFAs on pulmonary function, water content, morphology, and LBP, CD14, TNF-α, and IL-6 levels were observed in rats subjected to hemorrhagic shock, while the effect of PHSML intravenous infusion on the beneficial effect of ω-3 PUFAs also was investigated. In addition, the effect of ω-3 PUFAs on the endotoxin contents in mesenteric lymph were detected. Hemorrhagic shock-induced ALI was characterized by increased functional residual capacity (FRC), lung resistance (RI), inspiratory capacity (IC), respiratory frequency, water contents and structural damage, along with increases in LBP, IL-6, and TNF-α. ω-3 PUFAs treatment reduced FRC, RI, IC, frequency, water contents, LBP, IL-6, TNF-α, and alleviated morphological damage. In contrast, PHSML infusion abolished the advantageous effects of ω-3 PUFAs on the above indices and CD14. Furthermore, the endotoxin level of PHSML was significantly enhanced, but declined following ω-3 PUFAs administration. These findings together suggested that treatment with ω-3 PUFAs ameliorates hemorrhagic shock-induced ALI, which is associated with reduced endotoxin contained in PHSML.

Usefulness of intraoperative monitoring for mesenteric lymph node metastasis in transplanted free jejunum.

We herein report a rare case of a patient with hypopharyngeal squamous cell carcinoma (SCC) who presented with recurrent metastasis in the mesenteric lymph node of a transplanted jejunum. Removal of the metastatic lymph node required resection of the nutrient vessels which risked the current state of the transplanted jejunum. Importantly, although the nutrient vessels were resected, the jejunum did not become necrotic. This case and another similar case indicate that it may be possible to predict the viability of a transplanted jejunum where jejunal nutrient vessels must subsequently be resected. Key indicators for jejunal survival include determining jejunal blood flow by intraoperative indocyanine green fluorescence imaging, confirming good jejunal color and observation of peristaltic movement by intraoperative blood flow blockage of nutrient vessels. In conclusion, if intraoperative indocyanine green fluorescence imaging in the entire jejunum can be confirmed, there is a high possibility that the jejunum can be well preserved. The clinical presentation and clinical course are described with a proposed new schema of the resectable site of the transplanted jejunal mesentery.

Salvage surgery for mesenteric lymph node metastasis by resection of the first jejunal flap and reconstruction with the second jejunal flap.

We report a case of a second free jejunal transfer to treat metastasis in the mesenteric lymph node of the first jejunal flap. A 73-year-old man underwent total pharyngolaryngectomy, bilateral neck dissection, and free jejunal transfer for recurrent hypopharyngeal cancer [left pyriform sinus, pT2N0, moderately differentiated squamous cell carcinoma (SCC)] after radiotherapy. Seven years post-surgery, he underwent transoral videolaryngoscopic surgery for oropharyngeal cancer (soft palate, pT1N0, well-differentiated SCC). Ten years after the first jejunal transfer, metastasis was found in the mesenteric lymph node surrounding the jejunal flap's vascular pedicle. Under general anesthesia, resection of the first jejunum including the affected lymph node, and second jejunal transfer were performed. Lymph node pathological examination revealed poorly differentiated SCC, compatible with pharyngeal cancer metastasis. After neck dissection and jejunal flap transfer, lymphatic collateral pathways toward the flap's mesenteric lymph node might form. Possibly, hypopharyngeal or oropharyngeal cancer metastasized via this pathway.