Cancers (Basel). 2020 Oct 6;12(10):E2868.
Authors: Karagiannidis I, de Santana Van Vilet E, Said Abu Egal E, Phinney B, Jacenik D, Prossnitz ER, Beswick EJ
Abstract:
Tumor-associated macrophages (TAMs) in the gastrointestinal tumor microenvironment (TME) are known to polarize into populations exhibiting pro- or anti-tumoral activity in response to stimuli such as growth factors and cytokines. Our previous work has recognized granulocyte colony-stimulating factor (G-CSF) as a cytokine capable of influencing immune cells of the TME exhibiting pro-tumoral activity. Here, we aimed to focus on how G-CSF regulates TAM phenotype and function and the effects on gastrointestinal (GI) tumor progression. Thus, wildtype (WT) and G-CSFR-/- macrophages were examined for cytokine production, gene expression, and transcription factor activity. Adoptive transfer of WT or G-CSFR-/- macrophages into tumor-bearing mice was performed to study their influence in the progression of colon (MC38) and pancreatic (PK5L1940) tumor mouse models. Finally, the difference in cytotoxic potential between WT and G-CSFR-/- macrophages was examined both in vitro and in vivo. Our results indicate that G-CSF promotes increased IL-10 production and decreased IL-12 production, which was reversed in G-CSFR-/- macrophages for a pro-inflammatory phenotype. Furthermore, G-CSFR-/- macrophages were characterized by higher levels of NOS2 expression and NO production, which led to greater tumor related cytotoxicity both in vitro and in vivo. Our results suggest that in the absence of G-CSFR, macrophage-related tumor cytotoxicity was amplified. These findings, along with our previous reports, pinpoint G-CSF /G-CSFR as a prominent target for possible clinical applications that aim to control the TME and the GI tumor progression.
PMID: 33036138
Front Immunol. 2020 Sep 15;11:1885
Authors: Karagiannidis I, Jerman SJ, Jacenik D, Phinney BB, Yao R, Prossnitz ER, Beswick EJ
Abstract: Cytokines are known to shape the tumor microenvironment and although progress has been made in understanding their role in carcinogenesis, much remains to learn regarding their role in tumor growth and progression. We have identified granulocyte colony-stimulating factor (G-CSF) as one such cytokine, showing that G-CSF is linked with metastasis in human gastrointestinal tumors and neutralizing G-CSF in a mouse model of colitis-associated cancer is protective. Here, we set out to identify the role of G-CSF and its receptor, G-CSFR, in CD4+ and CD8+ T cell responses in the tumor microenvironment. MC38 colon cancer cells were injected into WT, G-CSFR-/- mice, or Rag2-/- mice. Flow cytometry, Real Time PCR and Multiplex cytokine array analysis were used for in vitro T cell phenotype analysis. Adoptive transfer of WT or G-CSFR-/- CD4+ of CD8+ T cells were performed. Mouse tumor size, cytokine expression, T cell phenotype, and cytotoxic activity were analyzed. We established that in G-CSFR-/- mice, tumor growth of MC38 colon cancer cells is significantly decreased. T cell phenotype and cytokine production were also altered, as both in vitro and in vivo approaches revealed that the G-CSF/G-CSFR stimulate IL-10-producing, FoxP3-expressing CD4+ and CD8+ T cells, whereas G-CSFR-/- T cells exhibit increased IFNγ and IL-17A production, leading to increased cytotoxic activity in the tumor microenvironment. Furthermore, peritumoral injection of recombinant IFNγ or IL-17A inhibited colon and pancreas tumor growth compared to controls. Taken together, our data reveal an unknown mechanism by which G-CSF, through its receptor G-CSFR, promotes an inhibitory Treg phenotype that limits tumor immune responses and furthermore suggest that targeting this cytokine/receptor axis could represent a novel therapeutic approach for gastrointestinal, and likely other tumors with high expression of these factors.
PMID: 33042110
J Bone Joint Surg Am. 2020 Oct 21;102(20):1784-1791
Authors: Shaw JD, Brodke DS, Williams DL, Ashton NN
Abstract
BACKGROUND: Bacterial biofilms pose a challenge in treating implant-associated infections. Biofilms provide bacteria with protection against antimicrobial agents and the immune response and often are invisible to the naked eye. As a biofilm-disclosing agent, methylene blue (MB) has shown promise, but lacks rigorous in vitro evaluation. The purposes of the present study were to assess MB as a biofilm-disclosing agent in vitro for common biofilm-forming organisms and to determine performance characteristics across implant materials and healthy tissue types.
METHODS: Staphylococcus aureus (ATCC 6538) and Pseudomonas aeruginosa (ATCC 27853) biofilms were grown on culture for 2 days in CDC biofilm reactors on titanium, cobalt chromium, polyethylene, and polyether ether ketone (PEEK) coupons. Biofilms were stained with MB solutions of either 0.005% or 0.01% and then were washed with normal saline solution. Digital photographs were obtained to compare the visual sensitivity of the blue dye at these dilutions. Scanning electron microscopy (SEM) was performed to confirm the absence or presence of biofilm on MB-stained areas. Uninoculated controls were also assessed. Healthy adult sheep tissues were also stained to determine the staining characteristics of the host tissue. ImageJ was used to determine the relative blue intensity of stained implants and tissues compared with standard curves.
RESULTS: S. aureus and P. aeruginosa biofilms stained avidly on titanium, cobalt chromium, polyethylene, and PEEK coupons. There was visible dose-dependent staining based on dye concentration. MB was visible only where biofilms were present as confirmed by SEM. MB did not stain uninoculated controls. Articular cartilage and meniscus demonstrated appreciable staining; bone, tendon, muscle, nerve, and fat did not. Bacterial biofilms demonstrated both dose-dependent and species-specific staining.
CONCLUSIONS: MB is an effective disclosing agent for S. aureus and P. aeruginosa biofilms in vitro. MB did not stain implant materials, nor did it stain most healthy tissues in vitro. MB may allow surgeons to see biofilms and may allow for enhanced debridement once visualized.
PMID: 33086345 [PubMed - as supplied by publisher]
Ann Surg. 2020 Oct 19;:
Authors: Pannucci CJ, Fleming KI, Varghese TK, Stringham J, Huang LC, Pickron TB, Prazak AM, Bertolaccini C, Momeni A
Abstract
OBJECTIVE: To examine the relationship between enoxaparin dose adequacy, quantified with anti-Factor Xa (aFXa) levels, and 90-day symptomatic venous thromboembolism (VTE) and post-operative bleeding.
SUMMARY BACKGROUND DATA: Surgical patients often develop "breakthrough" VTE events-those which occur despite receiving chemical anticoagulation. We hypothesize that surgical patients with low aFXa levels will be more likely to develop 90-day VTE, and those with high aFXa will be more likely to bleed.
METHODS: Pooled analysis of eight clinical trials (N = 985) from a single institution over a four year period. Patients had peak steady state aFXa levels in response to a known initial enoxaparin dose, and were followed for 90 days. Survival analysis log-rank test examined associations between aFXa level category and 90-day symptomatic VTE & bleeding.
RESULTS: Among 985 patients, 2.3% (n = 23) had symptomatic 90-day VTE, 4.2% (n = 41) had 90-day clinically relevant bleeding, and 2.1% (n = 21) had major bleeding. Patients with initial low aFXa were significantly more likely to have 90-day VTE than patients with adequate or high aFXa (4.2% vs. 1.3%, p = 0.007). In a stratified analysis, this relationship was significant for patients who received twice daily (6.2% vs. 1.5%, p = 0.003), but not once daily (3.0% vs. 0.7%, p = 0.10) enoxaparin. No association was seen between high aFXa and 90-day clinically relevant bleeding (4.8% vs. 2.9%, p = 0.34) or major bleeding (3.6% vs. 1.6%, p = 0.18).
CONCLUSIONS: This manuscript establishes inadequate enoxaparin dosing as a plausible mechanism for breakthrough VTE in surgical patients, and identifies anticoagulant dose adequacy as a novel target for process improvement measures.
PMID: 33086312 [PubMed - as supplied by publisher]
N Engl J Med. 2020 Oct 22;383(17):1624-1634
Authors: Dellon ES, Peterson KA, Murray JA, Falk GW, Gonsalves N, Chehade M, Genta RM, Leung J, Khoury P, Klion AD, Hazan S, Vaezi M, Bledsoe AC, Durrani SR, Wang C, Shaw C, Chang AT, Singh B, Kamboj AP, Rasmussen HS, Rothenberg ME, Hirano I
Abstract
BACKGROUND: Eosinophilic gastritis and duodenitis are characterized by gastrointestinal mucosal eosinophilia, chronic symptoms, impaired quality of life, and a lack of adequate treatments. Mast-cell activity may contribute to the pathogenesis of the conditions. AK002 (lirentelimab) is an anti-Siglec-8 antibody that depletes eosinophils and inhibits mast cells and that has shown potential in animal models as a treatment for eosinophilic gastritis and duodenitis.
METHODS: In this phase 2 trial, we randomly assigned adults who had symptomatic eosinophilic gastritis, eosinophilic duodenitis, or both conditions in a 1:1:1 ratio to receive four monthly infusions of low-dose AK002, high-dose AK002, or placebo. The primary end point was the change in gastrointestinal eosinophil count from baseline to 2 weeks after the final dose; to maximize statistical power, we evaluated this end point in the placebo group as compared with the combined AK002 group. Secondary end points were treatment response (>30% reduction in total symptom score and >75% reduction in gastrointestinal eosinophil count) and the change in total symptom score.
RESULTS: Of the 65 patients who underwent randomization, 43 were assigned to receive AK002 and 22 were assigned to receive placebo. The mean percentage change in gastrointestinal eosinophil count was -86% in the combined AK002 group, as compared with 9% in the placebo group (least-squares mean difference, -98 percentage points; 95% confidence interval [CI], -121 to -76; P<0.001). Treatment response occurred in 63% of the patients who received AK002 and in 5% of the patients who received placebo (difference, 58 percentage points; 95% CI, 36 to 74; P<0.001). The mean change in total symptom score was -48% with AK002 and -22% with placebo (least-squares mean difference, -26 percentage points; 95% CI, -44 to -9; P = 0.004). Adverse events associated with AK002 were similar to those with placebo, with the exception of higher percentages of patients having mild-to-moderate infusion-related reactions with AK002 (60% in the combined AK002 group and 23% in the placebo group).
CONCLUSIONS: In patients with eosinophilic gastritis or duodenitis, AK002 reduced gastrointestinal eosinophils and symptoms. Infusion-related reactions were more common with AK002 than with placebo. (Funded by Allakos; ENIGMA ClinicalTrials.gov number, NCT03496571.).
PMID: 33085861 [PubMed - in process]
