Genome-wide analysis of circRNA regulation during spleen development of Chinese indigenous breed Meishan pigs.

BACKGROUND: Numerous circular RNAs (circRNAs) have been recently identified in porcine tissues and cell types. Nevertheless, their significance in porcine spleen development is yet unelucidated. Herein, we reported an extensive overlook of circRNA expression profile during spleen development in Meishan pigs. RESULTS: Overall, 39,641 circRNAs were identified from 6,914 host genes. Among them, many circRNAs are up- or down-regulated at different time points of pig spleen development. Using WGCNA analysis, we revealed two essential modules for protein-coding genes and circRNAs. Subsequent correlation analysis revealed 67 circRNAs/co-expressed genes that participated in immnue-associated networks. Furthermore, a competing endogenous RNA (ceRNA) network analysis of circRNAs revealed that 12 circRNAs modulated CD226, MBD2, SAMD3, SIT1, SRP14, SYTL3 gene expressions via acting as miRNA sponges. Moreover, the circRNA_21767/miR-202-3p axis regulated SIT1 expression in a ceRNA manner, which is critical for the immune-based regulation of spleen development in Meishan pigs. CONCLUSIONS: Overall, our results demonstrated that the circRNAs were differentially expressed during different stages of porcine spleen development, meanwhile the circRNAs interacted with immune-related genes in a ceRNA-based fashion. Moreover, we presented biomedical researchers with RNAseqTools, a user-friendly and powerful software for the visualization of transcriptome profile data.

Tissue distribution of stem cell factor in adults.

Stem cell factor (SCF) is an essential cytokine during development and is necessary for gametogenesis, hematopoiesis, mast cell development, stem cell function, and melanogenesis. Here, we measure SCF concentration and distribution in adult humans and mice using gene expression analysis, tissue staining, and organ protein lysates. We demonstrate continued SCF expression in many cell types and tissues into adulthood. Tissues with high expression in adult humans included stomach, spleen, kidney, lung, and pancreas. In mice, we found high SCF expression in the esophagus, ovary, uterus, kidney, and small intestine. Future studies may correlate our findings of increased, organ-specific SCF concentrations within adult tissues with increased risk of SCF/CD117-related disease.

Ovarian Accumulation of Nanoemulsions: Impact of Mice Age and Particle Size.

Nanotechnology in the field of drug delivery comes with great benefits due to the unique physicochemical properties of newly developed nanocarriers. However, they may come as well with severe toxicological side effects because of unwanted accumulation in organs outside of their targeted site of actions. Several studies showed an unintended accumulation of various nanocarriers in female sex organs, especially in the ovaries. Some led to inflammation, fibrosis, or decreasing follicle numbers. However, none of these studies investigated ovarian accumulation in context to both reproductive aging and particle size. Besides the influences of particle size, the biodistribution profile may be altered as well by reproductive aging because of reduced capacities of the reticuloendothelial system (RES), changes in sex steroid hormone levels as well as altering ovarian stromal blood flow. This systematic investigation of the biodistribution of intravenously (i.v) injected nanoemulsions revealed significant dependencies on the two parameters particle size and age starting from juvenile prepubescent to senescent mice. Using fluorescent in vivo and ex vivo imaging, prepubescent mice showed nearly no accumulation of nanoemulsion in their uteri and ovaries, but high accumulations in the organs of the RES liver and spleen independently of the particle size. In fertile adult mice, the accumulation increased significantly in the ovaries with an increased particle size of the nanoemulsions by nearly doubling the portion of the average radiant efficiency (PARE) to ~10% of the total measured signal of all excised organs. With reproductive aging and hence loss of fertility in senescent mice, the accumulation decreased again to moderate levels, again independently of the particle size. In conclusion, the ovarian accumulation of these nanocarriers depended on both the age plus the particle size during maturity.

Alternative pathways for the development of lymphoid structures in humans.

Lymphoid tissue inducer (LTi) cells are critical for inducing the differentiation of most secondary lymphoid organs (SLOs) in mice. In humans, JAK3 and γc deficiencies result in severe combined immunodeficiency (SCIDs) characterized by an absence of T cells, natural killer cells, innate lymphoid cells (ILCs), and presumably LTi cells. Some of these patients have undergone allogeneic stem cell transplantation (HSCT) in the absence of myeloablation, which leads to donor T cell engraftment, while other leukocyte subsets are of host origin. By using MRI to look for SLOs in nine of these patients 16 to 44 y after HSCT, we discovered that SLOs were exclusively found in the three areas of the abdomen that drain the intestinal tract. A postmortem examination of a child with γc-SCID who had died 3.5 mo after HSCT showed corticomedullary differentiation in the thymus, T cell zones in the spleen, and the appendix, but in neither lymph nodes nor Peyer patches. Tertiary lymphoid organs were observed in the lung. No RAR-related orphan receptor-positive LTi cells could be detected in the existing lymphoid structures. These results suggest that while LTi cells are required for the genesis of most SLOs in humans, SLO in the appendix and in gut-draining areas, as well as tertiary lymphoid organs, can be generated likely by LTi cell-independent mechanisms.

The Lab4P Consortium of Probiotics Attenuates Atherosclerosis in LDL Receptor Deficient Mice Fed a High Fat Diet and Causes Plaque Stabilization by Inhibiting Inflammation and Several Pro-Atherogenic Processes.

SCOPE: Previous studies show that Lab4 probiotic consortium plus Lactobacillus plantarum CUL66 (Lab4P) reduces diet-induced weight gain and plasma cholesterol levels in C57BL/6J mice fed a high fat diet (HFD). The effect of Lab4P on atherosclerosis is not known and is therefore investigated. METHODS AND RESULTS: Atherosclerosis-associated parameters are analyzed in LDL receptor deficient mice fed HFD for 12 weeks alone or supplemented with Lab4P. Lab4P increases plasma HDL and triglyceride levels and decreases LDL/VLDL levels. Lab4P also reduces plaque burden and content of lipids and macrophages, indicative of dampened inflammation, and increases smooth muscle cell content, a marker of plaque stabilization. Atherosclerosis arrays show that Lab4P alters the liver expression of 19 key disease-associated genes. Lab4P also decreases the frequency of macrophages and T-cells in the bone marrow. In vitro assays using conditioned media from probiotic bacteria demonstrates attenuation of several atherosclerosis-associated processes in vitro such as chemokine-driven monocytic migration, proliferation of monocytes and macrophages, foam cell formation and associated changes in expression of key genes, and proliferation and migration of vascular smooth muscle cells. CONCLUSION: This study provides new insights into the anti-atherogenic actions of Lab4P together with the underlying mechanisms and supports further assessments in human trials.

Splenic volume on computed tomography scans is associated with mortality in patients with sepsis.

OBJECTIVES: The spleen is a key organ of the immune system. Asplenia has been reported to increase the risk of sepsis from overwhelming post-splenectomy infection. However, there are few reports on the association between splenic volume and mortality in patients with no history of splenectomy. This study focused on splenic volume of patients with sepsis and evaluated the association between splenic volume and mortality. METHODS: We retrospectively investigated 232 patients with sepsis. The splenic volume was calculated by using computed tomography scans obtained on admission. The patients were categorized into tertiles based on their splenic volume, and the relationship between splenic volume and mortality was evaluated. Odds ratio curves based on splenic volume were created to assess the continuous associations between splenic volume and outcome with a logistic regression model. RESULTS: The patients with sepsis were divided into three groups according to the first (73.6cm3) and second (128.7cm3) tertile values of splenic volume. Kaplan-Meier estimation of the probability of the patients' survival followed up to 28 days showed significant differences between the groups (p=0.03). The hazard ratio for 28-day mortality in the first tertile group was 3.46 (95% CI 1.3-10.2; p=0.01) as compared with patients in the third tertile group. Patients with smaller spleens had increased odds ratios for mortality in the logistic regression model. CONCLUSIONS: Splenic volume appeared to be an independent predictor of poor prognosis.

Anatomy of teleost fish immune structures and organs.

The function of a tissue is determined by its construction and cellular composition. The action of different genes can thus only be understood properly when seen in the context of the environment in which they are expressed and function. We now experience a renaissance in morphological research in fish, not only because, surprisingly enough, large structures have remained un-described until recently, but also because improved methods for studying morphological characteristics in combination with expression analysis are at hand. In this review, we address anatomical features of teleost immune tissues. There are approximately 30,000 known teleost fish species and only a minor portion of them have been studied. We aim our review at the Atlantic salmon (Salmo salar) and other salmonids, but when applicable, we also present information from other species. Our focus is the anatomy of the kidney, thymus, spleen, the interbranchial lymphoid tissue (ILT), the newly discovered salmonid cloacal bursa and the naso-pharynx associated lymphoid tissue (NALT).

Spleen: Development, anatomy and reactive lymphoid proliferations.

The unique architecture of the spleen enables it to play a key role in the interactions between the circulatory, reticuloendothelial and immune systems. Response to circulating antigens in the setting of infection, autoimmune disease or other conditions may result in a range of benign lymphoid proliferations. Moreover, patients with underlying immune deficiency may also show abnormal lymphoid proliferations within the spleen. This review will highlight the histologic, immunophenotypic and clinical features of reactive lymphoid proliferations to aid in their recognition and provide a context for understanding their development in relation to normal splenic structure and function.

Clinical and muscle MRI features in a family with tubular aggregate myopathy and novel STIM1 mutation.

Heterozygous mutations in the stromal interaction molecule-1-gene (STIM1) cause a clinical phenotype varying from tubular aggregate myopathy with single or multiple signs of Stormorken syndrome to the full Stormorken phenotype. We identified a novel heterozygous mutation c.325C > T (p.H109Y) in the EF-hand domain of STIM1 in six patients of a large Belgian family, and performed a detailed clinical (N = 6), histopathological (N = 2) and whole-body muscle MRI (N = 3) study. The clinical phenotype was characterized by a slowly progressive, predominant proximal muscle weakness in all patients (100%), and additional exercise-induced myalgia in three (60%). Patients experienced symptom onset between 10 and 20 years, remained ambulatory into late adulthood, showed elevated serum creatine kinase levels and tubular aggregates in type 1 and type 2 fibers on muscle biopsy. Interestingly, jaw contractures and hyperlaxity, as well as non-muscular multisystemic features such as menorrhagia, easy bruising and ichthyosis occurred in one patient, and miosis in another. Whole-body muscle MRI revealed predominant involvement of superficial neck extensors, subscapularis, obliquus abdominis externus, lumbar extensors, rectus femoris, biceps femoris longus, medial head of gastrocnemius and flexor hallucis longus. Our findings in patients with myopathy with tubular aggregates and a STIM1 mutation further support the concept of a continuous spectrum with Stormorken syndrome.

Morphological characterization of postembryonic development of blood-spleen barrier in duck.

The spleen is the largest peripheral lymphoid organ and an important site of immune response, in which the blood-spleen barrier (BSB) plays a significant role to resist various pathogens. The BSB structure of duck spleen is different from that of chicken and mammals. However, no information about the development of BSB after the postembryonic age has been reported in ducks. The current study observed the spleen of 1, 7, 14, 21, 35, and 60-day-old ducks by light and electron microscopy to analyze the cellular structural development. The results showed that the spleen index was continuously increased from 1 to 14-day-old ducks. During their early age, the spleen of ducks showed no definite zone of white and red pulp, but the area of the white pulp was large compared to that of the red pulp. The diameter of the ellipsoid was constantly increased in up to 35-day-old duck spleen, while the periellipsoidal lymphatic sheath (PELS) and periarterial lymphatic sheath continuously developed after 1 D. The reticular fibers developed with age; their branching reached the ellipsoidal wall to show a developed framework in the BSB of 14-day-old ducks. After 7 D, the endothelial cells of the sheathed capillary showed a typical cuboidal shape; between these cells, the gaps increased as age advanced, while the thickness of the basement membrane and collagen fibers increased in 35-day-old ducks. The mechanical filtration function of BSB by intravenous injection showed a 1-layer ring of carbon particles restricted in the white pulp in 1-day-old duck spleen; however, in 14 to 60 D, these particles were restricted in the ellipsoid and PELS, forming 2-layer rings of carbon particles. Collectively, the cellular features of the duck BSB developed up to 35 D of postembryonic age to perform their immune function.

Developmental changes in myocardial B cells mirror changes in B cells associated with different organs.

The naive heart harbors a population of intravascular B cells that make close contact with the cardiac microvasculature. However, the timing of their appearance and their organ specificity remain unknown. To address this knowledge gap, we performed a systematic analysis of B cells isolated from the myocardium and other organs, from embryonic life to adulthood. We found that the phenotype of myocardial B cells changed dynamically during development. While neonatal heart B cells were mostly CD11b+ and CD11b- CD21-CD23-, adult B cells were predominantly CD11b-CD21+CD23+. Histological analysis and intravital microscopy of lung and liver showed that organ-associated B cells in contact with the microvascular endothelium were not specific to the heart. Flow cytometric analysis of perfused hearts, livers, lungs, and spleen showed that the dynamic changes in B cell subpopulations observed in the heart during development mirrored changes observed in the other organs. Single cell RNA sequencing (scRNAseq) analysis of B cells showed that myocardial B cells were part of a larger population of organ-associated B cells that had a distinct transcriptional profile. These findings broaden our understanding of the biology of myocardial-associated B cells and suggest that current models of the dynamics of naive B cells during development are incomplete.

Biochemical and imaging parameters in acid sphingomyelinase deficiency: Potential utility as biomarkers.

Acid Sphingomyelinase Deficiency (ASMD), or Niemann-Pick type A/B disease, is a rare lipid storage disorder leading to accumulation of sphingomyelin and its precursors primarily in macrophages. The disease has a broad phenotypic spectrum ranging from a fatal infantile form with severe neurological involvement (the infantile neurovisceral type) to a primarily visceral form with different degrees of pulmonary, liver, spleen and skeletal involvement (the chronic visceral type). With the upcoming possibility of treatment with enzyme replacement therapy, the need for biomarkers that predict or reflect disease progression has increased. Biomarkers should be validated for their use as surrogate markers of clinically relevant endpoints. In this review, clinically important endpoints as well as biochemical and imaging markers of ASMD are discussed and potential new biomarkers are identified. We suggest as the most promising biomarkers that may function as surrogate endpoints in the future: diffusion capacity measured by spirometry, spleen volume, platelet count, low-density lipoprotein cholesterol, liver fibrosis measured with a fibroscan, lysosphingomyelin and walked distance in six minutes. Currently, no biomarkers have been validated. Several plasma markers of lipid-laden cells, fibrosis or inflammation are of high potential as biomarkers and deserve further study. Based upon current guidelines for biomarkers, recommendations for the validation process are provided.

Lipoxin A4 suppresses angiotensin II type 1 receptor autoantibody in preeclampsia via modulating caspase-1.

Preeclampsia (PE) remains a leading cause of maternal and neonatal morbidity and mortality. Numerous studies have shown that women with PE develop autoantibody, termed angiotensin II type 1 receptor autoantibody (AT1-AA), and key features of the disease result from it. Emerging evidence has indicated that inflammatory cell necrosis, such as pyroptosis, could lead to autoantigen exposure and stimulate autoantibody production. Caspase-1, the central enzyme of inflammasome and key target of pyroptosis, may play roles in AT1R exposure and AT1-AA production. Exploring endogenous regulator that could inhibit AT1-AA production by targeting pyroptosis will be essential for treating PE. Lipoxin A4 (LXA4), endogenous dual anti-inflammatory and proresolving lipid mediator, may inhibit AT1-AA production via modulating caspase-1. Thus, we explore whether caspase-1 is essential for AT1-AA production and LXA4 inhibits AT1-AA via modulating caspase-1. PE patients and mice developed AT1-AA associated with caspase-1 activation. Caspase-1 deletion leaded to AT1-AA decrease in PE mice. Consistent with these findings, we confirmed caspase-1 activation, trophoblast pyroptosis and AT1R exposure in PE mice and trophoblast model, while caspase-1 deficiency showed decreased trophoblast pyroptosis and AT1R exposure in vitro and in vivo. Interestingly, LXA4 could suppress AT1-AA production via regulating caspase-1 as well as enhancing phagocytosis of dead trophoblasts by macrophages. These results suggest that caspase-1 promotes AT1-AA production via inducing trophoblast pyroptosis and AT1R exposure, while LXA4 suppresses AT1-AA production via modulating caspase-1, supporting caspase-1 serving as a therapeutic target for attenuating AT1-AA and LXA4 protecting patients from AT1-AA and PE.

Developmental and Tissue Patterns of the Basal Expression of Chicken Avian ß-Defensins.

Defensins are a class of antimicrobial peptides in vertebrates that function as the first line of innate immunity with potent antimicrobial and immunomodulatory activities. Fourteen defensins, namely, avian ß-defensin 1 to 14 (AvBD1-14), have been identified in chickens. Before characterizing the role of AvBDs in innate immunity during the early development of chickens, we collected tissue segments from the liver, spleen, and gastrointestinal (GI) tract including the esophagus, crop, proventriculus, gizzard, duodenum, jejunum, ileum, cecum, and colon from broilers at days 1, 3, 7, 14, and 28. After RNA isolation and reverse transcription, we determined the expression levels of the 14 AvBD genes in these tissues during the first 28 days after hatching by real-time PCR. The results suggested the AvBDs were widely expressed in the chicken liver, spleen, and gastrointestinal (GI) tract. Interestingly, we did not detect AvBD11 expressed in the GI tract, even in the liver and spleen. Additionally, AvBDs were differentially expressed in the chicken GI tract. AvBD5 and AvBD14 were expressed most abundantly in the proximal GI tract, especially the esophagus and crop. Moreover, AvBD5, AvBD7, AvBD9, and AvBD14 were expressed in an inverted-V pattern with the peak being the observed expression at days 3, 7, or 14 in the chicken spleen, esophagus, duodenum, and cecum. Other AvBDs presented biphasic or inverted-V expression patterns in different tissues. The expression levels of all detected AvBDs were strengthened after hatching rather than decreasing steadily. Therefore, AvBDs were found to be expressed widely in the chicken liver, spleen, and GI tract and their expression levels were primarily up regulated during the early development of chicken, implying the potential essential roles of AvBDs in early innate defense and infection resistance of chickens.

Keratinocyte-specific ablation of Mcpip1 impairs skin integrity and promotes local and systemic inflammation.

MCPIP1 (Regnase-1, encoded by the ZC3H12A gene) regulates the mRNA stability of several inflammatory cytokines. Due to the critical role of this RNA endonuclease in the suppression of inflammation, Mcpip1 deficiency in mice leads to the development of postnatal multiorgan inflammation and premature death. Here, we generated mice with conditional deletion of Mcpip1 in the epidermis (Mcpip1EKO). Mcpip1 loss in keratinocytes resulted in the upregulated expression of transcripts encoding factors related to inflammation and keratinocyte differentiation, such as IL-36α/γ cytokines, S100a8/a9 antibacterial peptides, and Sprr2d/2h proteins. Upon aging, the Mcpip1EKO mice showed impaired skin integrity that led to the progressive development of spontaneous skin pathology and systemic inflammation. Furthermore, we found that the lack of epidermal Mcpip1 expression impaired the balance of keratinocyte proliferation and differentiation. Overall, we provide evidence that keratinocyte-specific Mcpip1 activity is crucial for the maintenance of skin integrity as well as for the prevention of excessive local and systemic inflammation. KEY MESSAGES: Loss of murine epidermal Mcpip1 upregulates transcripts related to inflammation and keratinocyte differentiation. Keratinocyte Mcpip1 function is essential to maintain the integrity of skin in adult mice. Ablation of Mcpip1 in mouse epidermis leads to the development of local and systemic inflammation.

Splenic development and injury in premature lambs supported by the artificial placenta.

INTRODUCTION: The purpose of this study is to evaluate splenic effects during artificial placenta (AP) support. METHODS: AP lambs (118-121 d, n = 14) were delivered and placed on the AP support for a goal of 10-14 days. Cannulation used right jugular drainage and umbilical vein reinfusion. Early (ETC; 115-120 d; n = 7) and late (LTC; 125-131 d; n = 7) tissue controls were delivered and immediately sacrificed. Spleens were formalin fixed, H&E stained, and graded for injury, response to inflammation, and extramedullary hematopoiesis (EMH). CD68 and CD163 stains were used to assess for macrophage activation and density. Clinical variables were correlated with splenic scores. Groups were compared using Fisher's Exact Test and descriptive statistics. p < 0.05 indicated significance. RESULTS: Mean survival for AP lambs was 12 ±â€¯5 d. There was no necrosis found in any of the groups. Vascular congestion and sinusoidal histiocytosis did not significantly differ between AP and control groups (p = 0.72; p = 0.311). There were significantly more pigmented macrophages (p = 0.008), CD163 (p = <0.001), and CD68 (p = <0.001) stained cells in the AP group. ETC and LTC demonstrated more EMH than AP spleens (p = <0.001). CONCLUSIONS: During AP support, spleens appear to develop normally and exhibit an appropriate inflammatory response. After initiation of AP support, EMH transitions away from the spleen. STUDY TYPE: Research Paper/Therapeutic Potential. LEVEL OF EVIDENCE: N/A.

Loading ceftriaxone, vancomycin, and Bifidobacteria bifidum TMC3115 to neonatal mice could differently and consequently affect intestinal microbiota and immunity in adulthood.

Recent studies have demonstrated that antibiotics/or probiotics administration in early life play key roles on modulating intestinal microbiota and the alterations might cause long-lasting consequences both physiologically and immunologically. We investigated the effects of early life ceftriaxone, vancomycin and Bifidobacterium bifidum TMC3115 (TMC3115) treatment on intestinal microbiota and immunity both in neonates and adults even after termination of antibiotics exposure. We found that ceftriaxone and vancomycin, but not TMC3115, significantly altered the intestinal microbiota, serum total IgE level, and the morphology and function of the intestinal epithelium in the neonatal mice. In the adult stages, the diversity and composition of the intestinal microbiota were significantly different in the antibiotic-treated mice, and ceftriaxone-treated mice exhibited significantly higher serum total IgE and OVA-specific IgE levels. TMC3115 significantly mitigated the alteration of intestinal microbiota caused by ceftriaxone not vancomycin. Antibiotics and TMC3115 can differently modulate intestinal microbiota and SCFAs metabolism, affecting the development and function of the immunity and intestinal epithelium to different degrees in neonatal mice. Neonatal ceftriaxone-induced abnormal intestinal microbiota, immunity and epithelium could last to adulthood partly, which might be associated with the enhancement of host susceptibility to IgE-mediated allergies and related immune responses, TMC3115 may protect against the side effects of antibiotic treatment, at least partly.

Hematological and immunological impairment following in-utero and postnatal exposure to aluminum sulfate in female offspring of albino rats.

Aim: Aluminum (Al) is a ubiquitous element extensively utilized in many products like food additives, pharmaceuticals, and vaccines, but its hematotoxic and immunotoxic effects are not entirely clarified. The present study explored the developmental hematotoxic and immunotoxic properties of aluminum sulfate (AS) in rats' offspring. Methods: Forty female offspring (10 rats each) were given three incremental AS doses plus a control group, from conception through lactation and after weaning until reached eight weeks old (near adults). Spleen relative weights along with total and differential blood counts were evaluated. Spectroscopic Al levels in spleen and brain were analyzed. Three immunoglobulins (IgG, IgM, and IgE) and two cytokines, interferon-γ and tumor necrosis factor-α, were measured through the ELISA technique. Results: The results revealed a significant relative increase in splenic weights mostly observed in the highest AS dose treated group. Reduction in the total leukocytic count was noticed in the three AS treated groups with relative lymphocytosis. Additionally, a significant decline in RBCs counts and hemoglobin concentrations were recorded. Tumor necrosis factor-α was significantly elevated in the three Al treated groups, while, interferon- γ showed a non-significant reduction compared to the control group. A significant increment in IgG and decline in IgE concentrations with no change in IgM level among groups were observed. Conclusion: Perinatal AS exposure caused mostly non-linear dose-dependent hematotoxicity and immunological impairment especially for the acquired immunity either cellular or humoral. Further studies can examine the immunotoxic effect of Al on male offspring during different stages of immune development.