Immunohistological Assessment Research Articles

Immunohistological Assessment of Male Germ Cell Apoptosis, and Histological Observation of Seminiferous Tubules and Epididymides According to Temporal Testicular Regulation in the Large Japanese Field Mouse <i>(Apodemus speciosus )</i>

Immunohistological Assessment of Male Germ Cell Apoptosis, and Histological Observation of Seminiferous Tubules and Epididymides According to Temporal Testicular Regulation in the Large Japanese Field Mouse <i>(Apodemus speciosus )</i>

Aloperine protects the testis against testicular ischemia/reperfusion injury in rats.

Testicular torsion/detorsion can cause testis loss and infertility. Aloperine is a major active alkaloid extracted from Sophora alopecuroides Linn. It has been shown to have organ-protective effects. However, the effects of aloperine on the testis and its underlying mechanisms remain unclear. This study investigated the effect of aloperine on testicular torsion/detorsion injury in rats. Male Sprague-Dawley rats were randomized to the sham-operated (sham), testicular I/R (TI/R), or aloperine preconditioning (ALOPre) or postconditioning (ALOPost) groups. All rats except for the sham-operated rats were subjected to 3h of right spermatic cord torsion (720°, clockwise), followed by 3h of detorsion. Aloperine (10mg/kg) was intravenously administered before testicular torsion (ALOPre) or at the onset of testicular detorsion (ALOPost). The therapeutic efficacy of aloperine was evaluated by histological analysis, oxidative stress evaluation, inflammatory response examination, apoptosis analysis, protein analysis, and immunohistological assessment. Compared with TI/R, aloperine protected both the ipsilateral and contralateral testes against unilateral testicular I/R, as evidenced by a reduced testicular weight to body weight (TW/BW) ratio (ALOPre: p=0.0037; ALOPost: p=0.0021) and volume (ALOPre: p=0.0020; ALOPost: p=0.0009), less structural damage with better Johnsen (ALOPre: p=0.0013; ALOPost: p=0.0021), and Cosentino scores (ALOPre: p<0.0001; ALOPost: p<0.0001), increased mean seminiferous tubule diameter and mean seminiferous tubule epithelial height, decreased testicular apoptosis, and less oxidative stress and inflammatory response. In addition, aloperine significantly stimulated the phosphorylation of signal transducer and activator of transcription (STAT)-3 in the ipsilateral testes following detorsion. Administration of Ag490 suppressed STAT-3 phosphorylation, thereby abrogating the protective effects exerted by aloperine on the ipsilateral testis. Aloperine has a strong testicular protective effect on the ipsilateral and contralateral testes after testicular torsion/detorsion. This aloperine-induced ipsilateral testicular protection is mediated via the STAT-3 signaling pathway.

Hydrogel coating containing heparin and cyclodextrin/paclitaxel inclusion complex for retrievable vena cava filter towards high biocompatibility and easy removal

Aiming to improve the retrieval rate of retrievable vena cava filters (RVCF) and extend its dwelling time in vivo, a novel hydrogel coating loaded with 10 mg/mL heparin and 30 mg/mL cyclodextrin/paclitaxel (PTX) inclusion complex (IC) was prepared. The drug-release behavior in the phosphate buffer solution demonstrated both heparin and PTX could be sustainably released over approximately two weeks. Furthermore, it was shown that the hydrogel-coated RVCF (HRVCF) with 10 mg/mL heparin and 30 mg/mL PTX IC effectively extended the blood clotting time to above the detection limit and inhibited EA.hy926 and CCC-SMC-1 cells' proliferation in vitro compared to the commercially available bare RVCF. Both the HRVCF and the bare RVCF were implanted into the vena cava of sheep and retrieved at at 2nd and 4th week after implantation, revealing that the HRVCF had a significantly higher retrieval rate of 67 % than the bare RVCF (0 %) at 4th week. Comprehensive analyses, including histological, immunohistological, and immunofluorescent assessments of the explanted veins demonstrated the HRVCF exhibited anti-hyperplasia and anticoagulation properties in vivo, attributable to the hydrogel coating, thereby improving the retrieval rate in sheep. Consequently, the as-prepared HRVCF shows promising potential for clinical application to enhance the retrieval rates of RVCFs.

Near-infrared Photoimmunotherapy Targeting Cancer-Associated Fibroblasts in Patient-Derived Xenografts using a Humanized anti-Fibroblast Activation Protein Antibody.

Esophageal cancer remains a highly aggressive malignancy with a poor prognosis, despite ongoing advancements in treatments such as immunotherapy. The tumor microenvironment, particularly cancer-associated fibroblasts (CAFs), plays a crucial role in driving the aggressiveness of esophageal cancer. In a previous study utilizing human-derived xenograft models, we successfully developed a novel cancer treatment that targeted CAFs with near-infrared photoimmunotherapy (NIR-PIT), as an adjuvant therapy. In this study, we sought to translate our findings toward clinical practice by employing patient-derived xenograft (PDX) models and utilizing humanized monoclonal antibodies, specifically Sibrotuzumab, which is anti-human fibroblast activation protein (FAP) antibody and already being investigated in clinical trials as monotherapy. PDX models derived from esophageal cancer patients were effectively established, preserving the expression of key biomarkers such as EGFR and FAP, as observed in primary tumors. The application of FAP-targeted NIR-PIT using Sibrotuzumab, conjugated with the photosensitizer IR700DX, exhibited precise binding and selective elimination of FAP-expressing fibroblasts in vitro. Notably, in our in vivo investigations using both cell line-derived xenograft and PDX models, FAP-targeted NIR-PIT led to significant inhibition of tumor progression compared to control groups, all without inducing adverse events such as weight loss. Immunohistological assessments revealed a substantial reduction in CAFs exclusively within the tumor microenvironment of both models, further supporting the efficacy of our approach. Thus, our study demonstrates the potential of CAF-targeted NIR-PIT employing Sibrotuzumab as a promising therapeutic avenue for clinical treatment of esophageal cancer patients.

Abstract 1433: FOXA1 alterations distinctively drive prostate tumorigenesis or therapy resistance in mice

Abstract Androgen receptor (AR) signaling is critical for survival of prostate cancer (PCa) cells, thus making androgen deprivation therapy (ADT; e.g., castration) as the mainstay for treatment. Notably, oncogenic functions of AR rely on chromatin-binding regulatory proteins, which includes a pioneer transcription factor called FOXA1. FOXA1 de-compacts chromatin to enable AR’s binding to the DNA and expression of it's target genes. Recently, our lab found FOXA1 alterations to recur within three distinct structural classes in over 35% of metastatic castration resistant PCa (mCRPC) in Caucasian men. Subsequent studies found FOXA1 mutations to be prevalent in over 40% of primary PCa in Chinese men, positioning FOXA1 as a principal oncogene in this disease. Yet, hitherto, no studies have defined the pathobiology of FOXA1 alterations in mouse models. Here, we have developed the first-in-field transgenic mice with conditional overexpression of FOXA1 mutants in the prostate luminal epithelia. We found truncal FOXA1 Class1 mutants to initiate luminal hyperplasia in a monogenic model, or hyperproliferative prostate adenocarcinoma in a compound Trp53-deficient genetic background. Mechanistically, Class1 mutants concurrently upregulate the AR and mTORC1/2 pathways to drive transformation, with this being the first report of FOXA1-driven PCa formation in mice. In contrast, FOXA1 Class2 mutants—which are acquired in mCRPC—do not drive prostate luminal transformation. Instead, single-cell multi-omics (RNA+ATAC) profiling of Class2-mutant mouse prostate tissue uncovered extensive transcriptional remodeling of epithelial cells into a luminal stem-like cell fate, leading to a dramatic 15-20-fold expansion of the progenitor population vs control tissue. These luminal stem cells are similar to the Club/Hillock cells detected in the human prostate that have been implicated in driving resistance to ADT. Consistently, we found Class2-mutant prostates to show minimal atrophy upon castration, with immunohistological assessment uncovering a higher density of Ki67+ luminal epithelial cells relative to wild type and Class1 tissues. Class2-mutant organoids also showed higher subcutaneous grafting ability in mice in limiting dilution assays. Mechanistically, we found the cistromically-dominant Class2 mutants to pioneer over 40,000 neo-enhancer elements harboring motifs of stemness-associated transcription factors, which in turn instruct the ADT-resistant luminal progenitor gene program. Altogether, findings from our mouse models uncover FOXA1’s versatility as a driver oncogene that, depending on the mutation type, either activates enhancer-wired luminal tumorigenesis (Class1-initiating event) or therapy resistance-associated stemness (Class2-promoting alteration) gene programs in the mouse prostate tissue. Citation Format: Sanjana Eyunni, Abhijit Parolia, Eleanor Young, James Matthew George, Rahul Mannan, Sandra E. Carson, Yuping Zhang, Jean Tien, Mustapha Jaber, Jie Luo, Matthew Pang, Rohit Mehra, Xuhong Cao, Fengyun Su, Rui Wang, Marcin Cieslik, Dong Kee Lee, Jianming Xu, Arul M. Chinnaiyan. FOXA1 alterations distinctively drive prostate tumorigenesis or therapy resistance in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1433.

Nerve Wrap for Local Delivery of FK506/Tacrolimus Accelerates Nerve Regeneration.

Peripheral nerve injuries (PNIs) occur frequently and can lead to devastating and permanent sensory and motor function disabilities. Systemic tacrolimus (FK506) administration has been shown to hasten recovery and improve functional outcomes after PNI repair. Unfortunately, high systemic levels of FK506 can result in adverse side effects. The localized administration of FK506 could provide the neuroregenerative benefits of FK506 while avoiding systemic, off-target side effects. This study investigates the utility of a novel FK506-impregnated polyester urethane urea (PEUU) nerve wrap to treat PNI in a previously validated rat infraorbital nerve (ION) transection and repair model. ION function was assessed by microelectrode recordings of trigeminal ganglion cells responding to controlled vibrissae deflections in ION-transected and -repaired animals, with and without the nerve wrap. Peristimulus time histograms (PSTHs) having 1 ms bins were constructed from spike times of individual single units. Responses to stimulus onsets (ON responses) were calculated during a 20 ms period beginning 1 ms after deflection onset; this epoch captures the initial, transient phase of the whisker-evoked response. Compared to no-wrap controls, rats with PEUU-FK506 wraps functionally recovered earlier, displaying larger response magnitudes. With nerve wrap treatment, FK506 blood levels up to six weeks were measured nearly at the limit of quantification (LOQ ≥ 2.0 ng/mL); whereas the drug concentrations within the ION and muscle were much higher, demonstrating the local delivery of FK506 to treat PNI. An immunohistological assessment of ION showed increased myelin expression for animals assigned to neurorrhaphy with PEUU-FK506 treatment compared to untreated or systemic-FK506-treated animals, suggesting that improved PNI outcomes using PEUU-FK506 is mediated by the modulation of Schwann cell activity.

Human Umbilical Cord Mesenchymal Stem Cell-Derived Exosomes Rescue Testicular Aging.

Testicular aging is associated with diminished fertility and certain age-related ailments, and effective therapeutic interventions remain elusive. Here, we probed the therapeutic efficacy of exosomes derived from human umbilical cord mesenchymal stem cells (hUMSC-Exos) in counteracting testicular aging. We employed a model of 22-month-old mice and administered intratesticular injections of hUMSC-Exos. Comprehensive analyses encompassing immunohistological, transcriptomic, and physiological assessments were conducted to evaluate the effects on testicular aging. Concurrently, we monitored alterations in macrophage polarization and the oxidative stress landscape within the testes. Finally, we performed bioinformatic analysis for miRNAs in hUMSC-Exos. Our data reveal that hUMSC-Exos administration leads to a marked reduction in aging-associated markers and cellular apoptosis while promoting cellular proliferation in aged testis. Importantly, hUMSC-Exos facilitated the restoration of spermatogenesis and elevated testosterone synthesis in aged mice. Furthermore, hUMSC-Exos could attenuate inflammation by driving the phenotypic shift of macrophages from M1 to M2 and suppress oxidative stress by reduced ROS production. Mechanistically, these efficacies against testicular aging may be mediated by hUMSC-Exos miRNAs. Our findings suggest that hUMSC-Exos therapy presents a viable strategy to ameliorate testicular aging, underscoring its potential therapeutic significance in managing testicular aging.

Characterizing post-branching nephrogenesis in the neonatal rabbit

Human nephrogenesis ends prior to birth in term infants (34–36 week gestation), with most (60%) nephrons forming in late gestation in two post-branching nephrogenesis (PBN) periods: arcading and lateral branch nephrogenesis. Preterm infants, however, must execute PBN postnatally. Extreme prematurity is associated with low nephron counts. Identifying additional model(s) that undergo PBN postnatally will help support postnatal PBN in preterm infants. The rabbit exhibits longer postnatal nephrogenesis than the mouse but whether it forms nephrons through PBN has not been determined. We performed morphologic and immunohistological assessments of rabbit nephrogenesis from birth (post-conceptual day 31 or 32) to PC49 using H&E and antibodies against SIX1, SIX2, WT1, ZO-1, and JAG1 in the postnatal period. We performed 3D rendering of the nephrogenic niche to assess for PBN, and supplemented the staining with RNAScope to map the expression of Six1, Six2 (nephron progenitors, NPC), and Ret (ureteric bud tip) transcripts to determine the nephrogenic niche postnatal lifespan. Unlike the mouse, rabbit SIX2 disappeared from NPC before SIX1, resembling the human niche. Active nephrogenesis as defined by the presence of SIX1 + naïve NPC/tip population persisted only until PC35–36 (3–5 postnatal days). 3D morphologic assessments of the cortical nephrons identified an elongated tubule with attached glomeruli extending below the UB tip, consistent with PBN arcades, but not with lateral branch nephrogenesis. We conclude that the rabbit shows morphologic and molecular evidence of PBN arcades continuing postnatally for a shorter period than previously thought. The rabbit is the first non-primate expressing SIX1 in the progenitor population. Our findings suggest that studies of arcading in postnatal nephrogenic niche should be performed within the first 5 days of life in the rabbit.

Cyclophosphamide enfeebles myocardial isometric contraction force via RIP1/RIP3/MLKL/TRPM7-mediated necroptosis

This study explores the negative impact of cyclophosphamide (CP) on cardiac contractility by specifically examining its effect on the active and passive tension of the cardiac muscle in-vitro and revealing the mechanism through which CP induces myocardial insult in-vivo. In young male Sprague-Dawley rats, cardiac toxicity was induced by a single intraperitoneal injection of CP (150 mg/kg body weight). Axial heart tissue slices were electrically stimulated, and the total isometric contraction force was measured at varying pretension levels. Blood and tissue biochemical assays, and histological/ immuno-histological assessments were conducted to evaluate the underlying molecular mechanisms. Statistical analysis shows that there is a significant difference between the drugged and the control groups in terms of the active tension values. Moreover, the pre-tension stress significantly affects both the active and passive tension values. CP altered heart, body, and heart-to-body weight, desolated cardiac muscle architecture, surged cardiac enzymes (CK-MB, LDH, and cTn l), augmented myocardial oxidative stressors (MDA), and weakened myocardial antioxidant status (SOD and GSH). Mechanistically, cyclophosphamide prompted the necroptotic trajectory evidenced by the activation of RIPK1, RIPK3, MLKL and TRPM7, the inhibition of caspase 8 and BCL2 and the upregulation of the protein/mRNA expression of TNF-α and TNFR1. This study identifies necroptosis as a key factor in cyclophosphamide-evoked myocardial contractility impairment, highlighting its potential as a target for alleviating antitumor-related myocardial damage. This innovative approach to investigating the underlying mechanisms of CP-induced cardiac toxicity offers valuable insights into the potential of developing new therapies to mitigate cyclophosphamide’s negative impact.

Abstract 2176: A cell mass-based platform for characterizing immune cell function and response to checkpoint blockade in primary blood and malignant fluid samples

Abstract Existing predictive biomarkers for immune checkpoint blockade (ICB) therapies that rely on characterization of tumor genomics or immunohistological assessment of the tumor microenvironment have demonstrated mixed success, with no single biomarker proving to be universally predictive of ICB treatment outcome. To complement these existing approaches, we present a workflow that relies on high-resolution single-cell mass measurements curated with CNN-based image classification to characterize T cell activation and functional response to treatment with ICB therapies. As a highly integrative measure of cellular phenotype, cell mass can be used as a label-free biomarker for characterizing immune cell function. For instance, upon activation with anti-CD3/CD28, T cells isolated from human PBMC showed a rapid and significant increase in cell mass. However, in T cells that had been repeatedly stimulated in vitro to generate a PD-1+ exhausted-like phenotype, this mass response to activation was blunted. We hypothesized that this variability in activation-induced mass response was the result of an altered balance of stimulatory and inhibitory “signal two” cues seen by the T cells. Consistent with this hypothesis, purified T cells stimulated with anti-CD3 alone (no co-stimulation) demonstrated a significantly smaller increase in cell mass when compared with those stimulated with both anti-CD3 and anti-CD28. Furthermore, the T cell response measured when unpurified PBMC were activated with anti-CD3 demonstrated an intermediate mass increase, suggesting contributions of both stimulatory and inhibitory signaling from other cells in the milieu. To explore how ICB treatment disrupts this co-stimulatory/inhibitory signaling balance, we measured T cell mass responses for samples treated with anti-CD3 alone or in combination with pembrolizumab, atezolizumab, nivolumab, or dostarlimab. These samples included PBMC isolated from blood and tumor/immune cell milieus isolated from malignant fluids (pleural effusions or abdominal ascites) collected from patients with advanced cancer. We found that T cells isolated from samples treated with both anti-CD3 and an ICB drug often showed a significantly greater mass increase than the same samples treated with anti-CD3 alone. This mass response showed significant heterogeneity across patients, with many samples showing no significant treatment effect. Despite all four of these therapies targeting ostensibly the same PD-1/PD-L1 signaling axis, we also found significant response heterogeneity to these different treatments within individual samples.These results suggest that mass response measurements capture biological heterogeneity associated with ICB response and may serve as a valuable complementary readout to existing biomarkers. Citation Format: Robert Kimmerling, Mark Stevens, Selim Olcum, Anthony Minnah, Madeleine Vacha, Rachel LaBella, Katie Katsis, Audrey Guo, Juanita Fujii, Zayna Shaheen, Srividya Sundaresan, Anobel Tamrazi, Cliff Reid. A cell mass-based platform for characterizing immune cell function and response to checkpoint blockade in primary blood and malignant fluid samples [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2176.

Canagliflozin Pretreatment Attenuates Myocardial Dysfunction and Improves Postcardiac Arrest Outcomes After Cardiac Arrest and Cardiopulmonary Resuscitation in Mice.

The SGLT2 inhibitor, canagliflozin, not only reduces glycemia in patients with type 2 diabetes but also exerts cardioprotective effects in individuals without diabetes. However, its potential beneficial effects in cardiac arrest have not been characterized. The purpose of this study was to examine the protective effect of canagliflozin pretreatment on postresuscitation-induced cardiac dysfunction in vivo. Male C57/BL6 mice were randomized to vehicle (sham and control) or canagliflozin treatment groups. All mice except for the sham-operated mice were subjected to potassium chloride-induced cardiac arrest followed by chest compressions and intravenous epinephrine for resuscitation. Canagliflozin therapy efficacies were evaluated by electrocardiogram, echocardiography, histological analysis, inflammatory response, serum markers of myocardial injury, protein phosphorylation analysis, and immunohistological assessment. Canagliflozin-pretreated mice exhibited a higher survival rate (P < 0.05), a shorter return of spontaneous circulation (ROSC) time (P < 0.01) and a higher neurological score (P < 0.01 or P < 0.001) than control mice after resuscitation. Canagliflozin was effective at improving cardiac arrest and resuscitation-associated cardiac dysfunction, indicated by increased left ventricular ejection fraction and fractional shortening (P < 0.001). Canagliflozin reduced serum levels of LDH, CK-MB and α-HBDH, ameliorated systemic inflammatory response, and diminished the incidence of early resuscitation-induced arrhythmia. Notably, canagliflozin promoted phosphorylation of cardiac STAT-3 postresuscitation. Furthermore, pharmacological inhibition of STAT-3 by Ag490 blunted STAT-3 phosphorylation and abolished the cardioprotective actions of canagliflozin. Canagliflozin offered a strong cardioprotective effect against cardiac arrest and resuscitation-induced cardiac dysfunction. This canagliflozin-induced cardioprotection is mediated by the STAT-3-dependent cell-survival signaling pathway.

Structural differences in bacterial lipopolysaccharides determine atherosclerotic plaque progression by regulating the accumulation of neutrophils

Background and aimsGut microbial lipopolysaccharide (LPS) induces endotoxemia, an independent risk factor for cardiovascular disease (CVD). However, no studies have demonstrated how structural differences in each bacterial LPS contribute to endotoxemia. Here, we investigated the effects of different acyl chains in the lipid A moiety of LPS on endotoxemia and the subsequent immune response and atherosclerotic plaque formation. MethodsApoe−/− mice were intraperitoneally administered 2 mg/kg of Escherichia coli-derived LPS (E. LPS, as a representative of hexa-acylated lipid A), Bacteroides-derived LPS (B. LPS, as a representative of penta- or tetra-acylated lipid A), or saline (control) once a week, six times. An immunohistological assessment was performed on plaque sections. ResultsE. LPS administration induced endotoxemia, but B. LPS and saline did not. In E. LPS-treated mice, total plaque areas in the aortic root were significantly increased, and neutrophil accumulation and increased formation of neutrophil extracellular traps (NETs) were observed at the plaque lesions, but not in B. LPS-treated mice. A single dose of E. LPS significantly increased the accumulation of neutrophils in plaque lesions on day 3, and NET formation on day 7. E. LPS also increased interleukin-1 beta (IL-1β) production in plaque lesions on day 7. Furthermore, NET formation and IL-1β production were also observed in human coronary plaques. ConclusionsWe identified a previously unknown link between structural differences in LPS and atherosclerosis. Lowering microbial LPS activity may reduce NET formation in plaques and prevent CVD progression.

A novel pathogenetic factor of laryngeal attack in hereditary angioedema? Involvement of protease activated receptor 1

BackgroundHereditary angioedema (HAE) is a rare, life-threatening disease. The knowledge about the molecular pathogenesis of HAE has derived mainly from investigating blood samples. However, limited data are available on the role of the molecular mechanisms in the affected tissues during HAE attack.ObjectiveThe aim of our study was to explore the histological changes occurring in HAE attacks.MethodsPost mortem macro-, microscopic and immunohistological assessment of upper airway tissues of a patient with HAE due to C1 inhibitor deficiency (C1-INH-HAE) type 2 who died from laryngeal HAE attack was compared with a non-HAE patient who died from other condition without any signs of angioedema.ResultsCompared to the control patient, we demonstrated stronger T cell/monocyte infiltration and a more intense C1-INH staining in the C1-INH-HAE patient. The expression of both bradykinin receptors (B1/B2) was observed with a slightly lower level in the C1-INH-HAE patient than in the control patient. PAR1 expression was strongly reduced in the C1-INH-HAE patient suggesting overactivation of this hyperpermeability inducing receptor.ConclusionOur unique case and novel results correspond to the knowledge about C1-INH and BDKRs observed in plasma; however, it revealed new information about the pathomechanism of HAE attack focusing on the potential involvement of PAR1 in edema formation. This observation, if it is verified by subcutaneous biopsy studies, may designate a new therapeutic target in HAE.

The relationship of oncotype Dx Recurrence Score (RS) with Ki 67 in early stage breast cancer patients in a community based cancer center in rural central Nebraska.

e12566 Background: Oncotype Dx recurrence score (RS), is a prognostic and predictive test utilized for decision making in adjuvant therapy of 0-3 node/hormone receptor positive(HR+)/ HER-2-negative early breast cancer. Ki-67 is a marker of proliferating cells and is associated with prognosis and response. Immunohistological (IHC) assessment of Ki 67 expression is less expensive and with the approval of CDK inhibitors in the high risk adjuvant setting, it is increasingly being utilized in clinical decision making. A moderate to strong correlation between Ki67 and Oncotype Dx RS has been reported in the literature. We sought to examine the relationship of Ki 67 to Oncotype Dx RS in a community-based cancer center in rural central Nebraska. Methods: Forty-three consecutive postmenopausal breast cancer patients(pts) diagnosed and treated at our community based cancer center between 2020-2021 with T1–2 N0-1 M0, HR+, HER-2-negative disease were evaluated for histological type, tumor size, Nottingham grade, HR levels, Ki 67 expression (low &lt; 10%, intermediate 10 ≥ Ki67 &lt; 25 high ≥ 25), and Oncotype Dx RS(low &lt;16,intermediate 16⩽RS&lt;26), high ⩾26). Ki 67 and Oncotype Dx RS were treated as continuous variables to calculate a Pearson correlation coefficient. Results: Mean age at diagnosis was 59.4 years (range 48-89). Mean tumor diameter was 15.6 mm. 78.9% were intermediate histologic grade and 9.7% patients had lymph node involvement. Median expression of ER and PR were 90% (5-100) and 70% (0-100), respectively. The mean Ki 67 value was 17.5 (range 5-60 %), and mean Oncotype RS was 14.4 (range 4-34). There was a positive linear correlation between Ki 67 expression and Oncotype Dx RS (Pearson Correlation Coefficient=0.49, P-value &lt;0.001). The vast majority of high Ki 67 pts (80%) had high/intermediate Oncotype RS. All pts with low Ki 67 (100%) had low/intermediate RS. Conclusions: Our community based rural cancer center data support a linear, statistically significant, positive correlation between Ki 67 and Oncotype Dx RS in early stage 0-3 node/HR+ positive breast cancer pts. Increasing use of Ki 67 testing in different clinical settings will generate more data to better define this correlation.[Table: see text]

Locomotor Training Enhances Respiratory Plasticity in a Pre‐clinical Model of Cervical Spinal Cord Injury

Spinal cord injury (SCI) is a devastating and irreversible injury that impacts thousands of people each year. Most injuries occur at cervical levels, compromising the phrenic motor network, resulting in life‐threatening respiratory deficits. While there is mounting clinical and pre‐clinical evidence for spontaneous plasticity, it is limited, and life‐threatening deficits persist. One strategy for therapeutically enhancing plasticity is the use of activity‐based therapies, such as respiratory and locomotor training. Clinical studies using treadmill training have shown improved respiratory function for individuals with SCI. Therefore, the present work reverse translates these promising clinical findings back to animal models of mid‐cervical SCI to assess the effects of treadmill training on anatomical and functional respiratory plasticity after injury.Adult female Sprague‐Dawley rats (~200g) received a lateralized C3/4 contusive injury. One week post injury, the animals were blindly divided into two groups: untrained or treadmill trained (30 min, once a day, 5 days a week) for 4 weeks. Breathing behavior was measured each week using whole‐body plethysmography. After training completion, all animals were anatomically traced with retrograde and transsynaptic pseudorabies virus (PRV) to the left hemidiaphragm to label the phrenic motor network, ipsilateral to injury. Three days later, animals were anesthetized and diaphragm electromyography (dEMG) was performed to observe ipsilateral diaphragm deficits and respiratory recovery, and animals were perfused for histology. Immunohistological assessment was used to quantify interneuronal connectivity and density of descending serotonergic input to the phrenic motor network. Preliminary data demonstrated increased interneuronal connectivity with injured phrenic motor network, and increased serotonergic input to spinal networks caudal to injury. Electrophysiological assessment of diaphragm function revealed increased diaphragm activity ipsilateral to injury, after 4 weeks of training. Ongoing analyses will further elucidate the therapeutic effects of locomotor training for improving breathing post‐SCI.

Time-series biological responses toward decellularized bovine tendon graft and autograft for 52 consecutive weeks after rat anterior cruciate ligament reconstruction

There is an essential demand for developing biocompatible grafts for knee anterior cruciate ligament reconstruction (ACLR). This study investigated cell infiltration into decellularized bovine tendon xenografts using a rat knee ACLR model. Twelve-week-old Sprague–Dawley rats were used. At weeks 1, 2, 4, 8, 16, 26, and 52 (each period, n = 6) after ACLR, rats receiving decellularized bovine tendon (group D, n = 42) or autologous tendon (group A, n = 42) as grafts underwent peritibial bone tunnel bone mineral density (BMD), histological, and immunohistological assessments. BMD increased over time in both the groups until week 16 and then remained unchanged without exhibiting significant differences between the groups. Initially, cellularity in group D was lower than that in group A; however, by weeks 4–8, both the groups were comparable to the native anterior cruciate ligament group and cellularity remained unchanged until week 52. Initially, group A had more M1 macrophages, indicating inflammation, whereas group D had more M2 macrophages, indicating tissue regeneration. Nonetheless, the M1 and M2 macrophage counts of both the groups were comparable at most times. This study revealed the excellent recellularization and tendon–bone integration abilities of decellularized tendons using a cross-species model.

Safety of 222 nm UVC Irradiation to the Surgical Site in a Rabbit Model.

For the prevention of surgical site infection (SSI), continuous disinfection could be helpful. Short wavelength ultraviolet radiation C (UVC) is highly bactericidal but shows cytotoxicity. Radiation of UVC with a wavelength of 222 nm to the skin is considered to be safe because it only reaches the stratum corneum. However, the safety of 222 nm irradiation to the surgical field not covered with skin is unknown. The purpose of this study was to examine the safety of 222 nm UVC irradiation on a surgical field in a rabbit model. Five types of tissue were surgically exposed and irradiated with 222 or 254 nm UVC. Immunohistological assessment against cyclobutane pyrimidine dimer (CPD), an index of DNA damage by UVC, was performed. The CPD-positive cell rate was significantly higher in the 254 nm group than in the other groups in all tissues. A 222 nm group showed significantly more CPD than control in fat tissue, but no significant difference in all other tissues. In fat tissue collected 24 h after irradiation, the 254 nm group showed higher CPD than the other groups, while the 222 nm group had reduced to the control level. These data suggest that 222 nm UVC irradiation could be a new method to safely prevent SSI.

A multicenter, randomized, double-blind, placebo-controlled study to evaluate the efficacy of immunosuppression in biopsy-proven virus-negative myocarditis or inflammatory cardiomyopathy (IMPROVE-MC).

Myocarditis is frequently associated with poor prognosis as there is no evidence-based treatment. Therefore, current international recommendations indicate that a well-designed prospective trial to confirm benefits from immunosuppressive therapy is highly warranted. The aim of the IMPROVE-MC study is to assess the efficacy and safety of immunosuppressive treatment compared with placebo on top of the guideline-recommended medical therapy in patients with biopsy-proven virus-negative myocarditis/inflammatory cardiomyopathy. The IMPROVE-MC (ClinicalTrials.gov: NCT04654988) is a prospective, randomized, double-blind, placebo-controlled, parallel-group, multicenter trial that will recruit 100 adults, with biopsy-proven myocarditis/inflammatory cardiomyopathy, with left ventricular ejection fraction (LVEF) ≤ 45% and ≥ 3-month history of symptoms. Patients will be randomized (1:1 ratio) to a group treated with prednisone and azathioprine vs. placebo. Patients will undergo 1-year double-blind therapy followed by a 1-year observation period to assess the long-term effects of the treatment. Apart from a routine clinical work-up, all patients will undergo cardiac magnetic resonance (CMR) and biopsy during screening and 1 year after applying the therapy. Primary endpoint is a change from baseline in LVEF at 12 months. Secondary endpoints are related to clinical evaluation (including New York Heart Association class, distance in 6-minute walk test, number of patients with the need for hospitalization), laboratory findings (biomarkers of fibrosis and myocardial necrosis, concentration of anti-heart auto-antibodies, heart tissue immunohistologic assessment), diagnostic tools (e.g., changes of echocardiographic, CMR and Holter-ECG parameters) and quality of life. The IMPROVE-MC study will provide high-quality scientific data on the efficacy and safety of immunosuppressive therapy for patients with biopsy-proven myocarditis. Trial registration number and date of registration: ClinicalTrials.gov:NCT04654988; 04/12/2020.

Abstract 10612: Immune Cells in Calcific Aortic Valve Disease

Introduction: Calcific aortic valve disease is a multifaceted disease in which pathogenic mineralisation of the valvular tissue occurs in tandem with fibrocalcific remodelling of the aortic valve, resulting in a wide variety of clinical presentations. Immunity, both innate and adaptive have been shown to play important roles in chronic cardiovascular diseases. Noteably, 15% of cells within healthy aortic valves are up to hematopoietic origin and these populations are further increased within calcified valves however, the role of the immune system within CAVD remains to be elucidated. Objectives: Investigate the prevalence and distribution of immune cells within CAVD. Methods &amp; Results: Human calcified aortic heart valves were obtained from valve replacement surgeries. Immunohistological assessment of immune cells within the tissue was conducted, with the presence of T cells, B cells, macrophages and dendritic cells detected in the vicinity of calcific nodules. Flow cytometry analysis of cells isolated from the valve was conducted. 69% of cells isolated from the valve were CD45+, with 57% and 42% of CD45+ CD3+ presenting as CD8+ and CD4+ respectively. Within the CD8+ population, 56% of these were central memory CD8+ T cells, with 24% as activated CD8+ T cells. Likewise, within the CD4+ population 29.5% CD4+ cells were activated T cells and 55% central memory T cells. Small populations of naïve CD4+ and CD8+ T cells; 9% and 13% respectively, were present within the valve. CD45+, CD3+, CD4+/CD8+ cells were isolated via FACS and their global proteomic profile was analysed on the Thermo Scientific Lumos orbitrap mass spectrometer. IL-31RA was present within the T cell population, alongside MAPK pathway mediators were also present. Network analysis of T cell proteomics showed increased IL-4 and IL-13 pathways (p&lt;0.01) indicative of a Type II inflammatory pathway, correlating with the presence of basophils and eosinophils present within the valve. Conclusions: Prevalence of immune cells within the valve suggests an inflammatory role in the development of calcific aortic valve disease, with the prevalence of T cells within the valve suggesting an adaptive immune response may be central to the pathology of CAVD.

The Small Molecule Alpha-Synuclein Aggregator, FN075, Enhances Alpha-Synuclein Pathology in Subclinical AAV Rat Models.

Animal models of Parkinson’s disease, in which the human α-synuclein transgene is overexpressed in the nigrostriatal pathway using viral vectors, are widely considered to be the most relevant models of the human condition. However, although highly valid, these models have major limitations related to reliability and variability, with many animals exhibiting pronounced α-synuclein expression failing to demonstrate nigrostriatal neurodegeneration or motor dysfunction. Therefore, the aim of this study was to determine if sequential intra-nigral administration of AAV-α-synuclein followed by the small α-synuclein aggregating molecule, FN075, would enhance or precipitate the associated α-synucleinopathy, nigrostriatal pathology and motor dysfunction in subclinical models. Rats were given unilateral intra-nigral injections of AAV-α-synuclein (either wild-type or A53T mutant) followed four weeks later by a unilateral intra-nigral injection of FN075, after which they underwent behavioral testing for lateralized motor functionality until they were sacrificed for immunohistological assessment at 20 weeks after AAV administration. In line with expectations, both of the AAV vectors induced widespread overexpression of human α-synuclein in the substantia nigra and striatum. Sequential administration of FN075 significantly enhanced the α-synuclein pathology with increased density and accumulation of the pathological form of the protein phosphorylated at serine 129 (pS129-α-synuclein). However, despite this enhanced α-synuclein pathology, FN075 did not precipitate nigrostriatal degeneration or motor dysfunction in these subclinical AAV models. In conclusion, FN075 holds significant promise as an approach to enhancing the α-synuclein pathology in viral overexpression models, but further studies are required to determine if alternative administration regimes for this molecule could improve the reliability and variability in these models.