Novel Orally Administered Recombinant Anti-TNF Alpha Fusion Protein for the Treatment of Ulcerative Colitis: Results From a Phase 2a Clinical Trial.

BACKGROUND AND OBJECTIVE: OPRX-106 is an orally administered BY2 plant cell-expressing recombinant TNF fusion protein (TNFR). Oral administration of OPRX-106 was shown to be safe and effective in inducing favorable anti-inflammatory immune modulation in humans. The current study was aimed at determining the safety and efficacy of OPRX-106 in patients with ulcerative colitis (UC). METHODS: Twenty-five patients with active mild-to-moderate UC were enrolled in an open-label trial. Patients were randomized to receive 2 or 8 mg of OPRX-106 administered orally once daily, for 8 weeks. Patients were monitored for safety and efficacy including clinical response or clinical remission, based on the Mayo score. The histopathological improvement in Geboes score, calprotectin level and hs-CRP, and exploratory immune parameters by means of fluorescence-activated cell sorting and cytokine levels were monitored. RESULTS: Oral administration of OPRX-106 was found to be safe and well tolerated without absorption into the circulation. Out of 24 patients, 18 completed the trial. The analysis of the patients completing treatment demonstrated clinical efficacy as measured by clinical response or remission in 67% and 28%, respectively. Reduction in calprotectin levels and improved Geboes score were noted in the majority of the treated patients. The beneficial clinical effect was associated with an increase in a CD4+CD25+FoxP3 subset of suppressor lymphocytes and a reduction in interleukin 6 and interferon gamma serum levels. CONCLUSIONS: Oral administration of the nonabsorbable OPRX-106 is safe and effective in mild-to-moderate UC, and not associated with immune suppression, while inducing favorable anti-inflammatory immune modulation.

OXYGEN MITIGATES THE INFLAMMATORY RESPONSE IN A MODEL OF HEMORRHAGE AND ZYMOSAN-INDUCED INFLAMMATION.

Sequential insults (hits) may change the inflammatory reaction that develops in response to separate single hits (e.g., injury, infection); however, their effects on the long-term clinical outcome are still only partially elucidated. Double-hit models are typically severe and fatal. We characterized in C57BL/6 mice a moderate double-hit model of hemorrhage (35%-40% of total blood volume) and resuscitation, followed by peritoneal injection of zymosan A that induced local and systemic inflammation with 58% mortality. This model allowed exploration of the inflammatory response over time in the surviving mice. We show that after 2 days, mice subjected to the double-hit model had elevated proinflammatory systemic and local peritoneal cytokine response (interleukin [IL]-1ß, tumor necrosis factor-α, IL-6) and moderately elevated anti-inflammatory cytokines (IL-10, transforming growth factor-ß), compared with the single-hit and sham mice. However, this dynamically changed, and by day 7, proinflammatory cytokines were reduced, and anti-inflammatory cytokines were markedly (P < 0.05) elevated in the double-hit group. Mice in the double-hit group that inhaled 100% oxygen intermittently for 6 h every day exhibited markedly reduced serum proinflammatory cytokines as early as day 2 (P < 0.05), inhibited macrophage infiltration into the peritoneum (by 13-fold; P < 0.05), and substantially increased survival rates of 85% (P = 0.00144). Oxygen mitigates the inflammatory response and exerts a beneficial effect on survival in a double-hit model of hemorrhage and zymosan-induced inflammation.

Tumor cell-macrophage interactions increase angiogenesis through secretion of EMMPRIN.

Tumor macrophages are generally considered to be alternatively/M2 activated to induce secretion of pro-angiogenic factors such as VEGF and MMPs. EMMPRIN (CD147, basigin) is overexpressed in many tumor types, and has been shown to induce fibroblasts and endothelial cell expression of MMPs and VEGF. We first show that tumor cell interactions with macrophages resulted in increased expression of EMMPRIN and induction of MMP-9 and VEGF. Human A498 renal carcinoma or MCF-7 breast carcinoma cell lines were co-cultured with the U937 monocytic-like cell line in the presence of TNFα (1 ng/ml). Membranal EMMPRIN expression was increased in the co-cultures (by 3-4-folds, p < 0.01), as was the secretion of MMP-9 and VEGF (by 2-5-folds for both MMP-9 and VEGF, p < 0.01), relative to the single cultures with TNFα. Investigating the regulatory mechanisms, we show that EMMPRIN was post-translationally regulated by miR-146a, as no change was observed in the tumoral expression of EMMPRIN mRNA during co-culture, expression of miR-146a was increased and its neutralization by its antagomir inhibited EMMPRIN expression. The secretion of EMMPRIN was also enhanced (by 2-3-folds, p < 0.05, only in the A498 co-culture) via shedding off of the membranal protein by a serine protease that is yet to be identified, as demonstrated by the use of wide range protease inhibitors. Finally, soluble EMMPRIN enhanced monocytic secretion of MMP-9 and VEGF, as inhibition of its expression levels by neutralizing anti-EMMPRIN or siRNA in the tumor cells lead to subsequent decreased induction of these two pro-angiogenic proteins. These results reveal a mechanism whereby tumor cell-macrophage interactions promote angiogenesis via an EMMPRIN-mediated pathway.

Dose-related effects of hyperoxia on the lung inflammatory response in septic rats.

We evaluated the effects of hyperoxia on pulmonary inflammatory changes in sepsis induced by cecal ligation and puncture (CLP) in rats. Seven groups were studied: sham-operated rats breathing air for 20 or 48 h; CLP breathing air for 20 or 48 h; and CLP + 100% oxygen for 20 h, or 70% oxygen for 48 h, or 100% oxygen intermittently (6 h/d) for 48 h. Video microscopy was used to monitor lung macromolecular leak, microvascular flow velocity, and shear rates, and lung morphometry was used for leukocyte infiltration and solid tissue area. Cell counts, tumor necrosis factor α, and nitrites were determined in peripheral blood and lung lavage fluid. Expression of adhesion molecules in blood leukocytes was evaluated by flow cytometry. Cecal ligation and puncture induced inflammation manifested in leukopenia, left shift, thrombocytopenia, increased expression of L selectin and CD11, increased serum and lavage fluid tumor necrosis factor α and leukocytes, and increased lung tissue area, macromolecular leak, and sequestration of leukocytes. Inhalation of 100% oxygen for 20 h increased nitrites (P < 0.01) and decreased leukocyte count in lavage fluid (P < 0.05) and attenuated lung macromolecular leak and changes in solid tissue area (P < 0.01). Inhalation of 70% oxygen (48 h) attenuated expression of adhesion molecules (P < 0.001) but failed to attenuate markers of lung inflammation. In contrast, intermittent 100% oxygen exerted favorable effects on markers of inflammation, attenuated leukocyte expression of L selectin and CD11 (P < 0.01), decreased pulmonary sequestration of leukocytes (P < 0.001), and ameliorated changes in macromolecular leak (P < 0.01) and lung solid tissue area (P < 0.05). Our data support the beneficial effects of safe subtoxic regimens of normobaric hyperoxia on the systemic and pulmonary inflammatory response following CLP.