mAb-treated Group Research Articles

Oxidative Stress-Responsive Apoptosis Inducing Protein (ORAIP) Plays a Critical Role in Dextran Sulfate Sodium-Induced Murine Model of Ulcerative Colitis.

Oxidative stress is implicated in the pathogenesis of various acute disorders including ischemia/reperfusion injury, ultraviolet/radiation burn, as well as chronic disorders such as dyslipidemia, atherosclerosis, diabetes mellitus, chronic renal disease, and inflammatory bowel disease (IBD). However, the precise mechanism involved remains to be clarified. We formerly identified a novel apoptosis-inducing humoral protein, in a hypoxia/reoxygenation-conditioned medium of cardiac myocytes, which proved to be 69th tyrosine-sulfated eukaryotic translation initiation factor 5A (eIF5A). We named this novel tyrosine-sulfated secreted form of eIF5A Oxidative Stress-Responsive Apoptosis-Inducing Protein (ORAIP). To investigate the role of ORAIP in a dextran sulfate sodium (DSS)-induced murine model of ulcerative colitis (UC), we analyzed the effects of in vivo treatment with anti-ORAIP neutralizing monoclonal antibody (mAb) on the DSS-induced disease exacerbation. The body weight in anti-ORAIP mAb-treated group was significantly heavier than that in a mouse IgG-treated control group on day 8 of DSS-treatment ((85.21 ± 1.03%) vs. (77.38 ± 2.07%); (mean ± SE0, n = 5 each, p < 0.01, t-test). In vivo anti-ORAIP mAb-treatment also significantly suppressed the shortening of colon length as well as Disease Activity Index (DAI) score ((5.00 ± 0.44) vs. (8.20 ± 0.37); (mean ± SE), n = 5 each, p < 0.001, t-test) by suppressing inflammation of the rectal tissue and apoptosis of intestinal mucosal cells. These data reveal the pivotal role of ORAIP in DSS-induced oxidative stress involved in an animal model of UC.

Amelioration of Collagen-Induced Arthritis in Rats by a Monoclonal Antibody against the Novel Epitope of Cysteine Protease from P. gingivalis

Abstract Background: The use of biological diseases-modifying anti-rheumatic drugs (bDAMRD) including anti-tumor necrosis factor-α (TNF-α) has revolutionized the therapy of rheumatoid arthritis (RA). However, approximately 30–40% of patients with RA do not response to anti-TNF therapy when used as the first-line bDMARD. Objective: The aim of the study is to develop a new, novel monoclonal antibody for the therapy of RA. Methods: Monoclonal antibody development: BALB/c mice were immunized with OVA-conjugated peptide for CIA. Spleen cells were collected for fusion with myeloma cells. The rats were divided into 6 groups: Normal control, CIA, IgG1(15 mg/kg)-treated CIA, low-mAb (3 mg/kg)-treated CIA, High-mAb (9 mg/kg)-treated CIA, and Enbrel (4.5 mg/kg)-treated CIA. Results: The monoclonal is only reacted to the immunized peptide and is IgG1 Kappa, high melting temperature with Tm=4.8, High binding to FCγRIIb and FCγR III, and low dissociation constant (Kd=19.6×10 −9) of Ag-mAb affinity. The mAb stains mainly on cytoplasm with several coarse discrete dots on SW982 cells. After treatment with this mAb in CIA, the mice have showed dose-dependent effects, improving articular index and ankle circumference, reduced inflammation and synovium proliferation, restored joint space narrowing, and cartilage on immunohistochemistry. The therapeutic results in the mAb-treated group has shown to be excellent in CIA animal RA model. Conclusion: We’ve generated a novel monoclonal antibody which has excellent therapeutic effects in the therapy of RA animal model. This study is the first time to demonstrate that targeting on the different signal pathway of CIA can have a promising effect on RA therapy.

Rate of Hypertensive Disorders of Pregnancy With Monoclonal Antibody Treatment for SARS-CoV-2 Infection [ID: 1376017

INTRODUCTION: SARS-CoV-2 infection among pregnant patients been associated with elevated rates of hypertensive disorders of pregnancy (HDP). We have demonstrated that monoclonal antibodies did not result in significantly different rates of severe COVID-19 in pregnancy. We undertook this study to determine whether HDP was altered with monoclonal antibody (mAb) treatment for SARS-CoV-2. METHODS: Retrospective cohort study approved by the IRB of University of Pittsburgh of patients aged 12 or older with a pregnancy episode and positive SARS-CoV-2 test in the UPMC health system. Among 663 patients, 403 received mAb treatment and 260 did not receive mAb. Chart review was performed for diagnosis of gestational hypertension (gHTN), preeclampsia without severe features, severe preeclampsia/HELLP syndrome, and postpartum hypertensive disorder with no antepartum diagnosis (PPHTN). Student’s t test was used to compare groups, and P&lt;.05 was considered significant. RESULTS: The majority of patients presented during the Omicron wave. In the mAb-treated group, 21.8% developed HDP, 13.2% gHTN, 2.5% nonsevere preeclampsia, 6.9% severe preeclampsia/HELLP, and 2.7% PPHTN. The group that received no mAb experienced rates that were not significantly different from the mAb treated: 17.3% HDP, 10.8% gHTN, 3.5% nonsevere preeclampsia, 2.3% severe preeclampsia/HELLP, and 1.9% PPHTN. CONCLUSION: The use of mAbs in pregnant patients infected with SARS-CoV-2 is not associated with a change in the rate of HDP with the Omicron variant. Patients treated with mAbs had a trend toward increased severe preeclampsia, although this was not statistically significant. An understanding of which populations benefit maximally from mAb treatment will assist in managing the most effective and efficient allocation of resources.

Protective effects of an anti-4-HNE monoclonal antibody against liver injury and lethality of endotoxemia in mice

4-hydroxy-2-nonenal (4-HNE) is a lipid peroxidation product that is known to be elevated during oxidative stress. During systemic inflammation and endotoxemia, plasma levels of 4-HNE are elevated in response to lipopolysaccharide (LPS) stimulation. 4-HNE is a highly reactive molecule due to its generation of both Schiff bases and Michael adducts with proteins, which may result in modulation of inflammatory signaling pathways. In this study, we report the production of a 4-HNE adduct-specific monoclonal antibody (mAb) and the effectiveness of the intravenous injection of this mAb (1 mg/kg) in ameliorating LPS (10 mg/kg, i.v.)-induced endotoxemia and liver injury in mice. Endotoxic lethality in control mAb-treated group was suppressed by the administration of anti-4-HNE mAb (75 vs. 27%). After LPS injection, we observed a significant increase in the plasma levels of AST, ALT, IL-6, TNF-α and MCP-1, and elevated expressions of IL-6, IL-10 and TNF-α in the liver. All these elevations were inhibited by anti-4-HNE mAb treatment. As to the underlining mechanism, anti-4-HNE mAb inhibited the elevation of plasma high mobility group box-1 (HMGB1) levels, the translocation and release of HMGB1 in the liver and the formation of 4-HNE adducts themselves, suggesting a functional role of extracellular 4-HNE adducts in hypercytokinemia and liver injury associated with HMGB1 mobilization. In summary, this study reveals a novel therapeutic application of anti-4-HNE mAb for endotoxemia.

Development of a Novel Humanized Monoclonal Antibody to Secreted Frizzled-Related Protein-2 That Inhibits Triple-Negative Breast Cancer and Angiosarcoma Growth In Vivo.

We previously reported that secreted frizzled-related protein-2 (SFRP2) is expressed in a variety of tumors, including sarcoma and breast carcinoma, and stimulates angiogenesis and inhibits tumor apoptosis. Therefore, we hypothesized that a humanized SFRP2 monoclonal antibody (hSFRP2 mAb) would inhibit tumor growth. The lead hSFRP2 antibody was tested against a cohort of 22 healthy donors using a time course T-cell assay to determine the relative risk of immunogenicity. To determine hSFRP2 mAb efficacy, nude mice were subcutaneously injected with SVR angiosarcoma cells and treated with hSFRP2 mAb 4mg/kg intravenously every 3days for 3weeks. We then injected Hs578T triple-negative breast cells into the mammary fat pad of nude mice and treated for 40days. Control mice received an immunoglobulin (Ig) G1 control. The SVR and Hs578T tumors were then stained using a TUNEL assay to detect apoptosis. Immunogenicity testing of hSFRP2 mAb did not induce proliferative responses using a simulation index (SI) ≥ 2.0 (p < 0.05) threshold in any of the healthy donors. SVR angiosarcoma tumor growth was inhibited in vivo, evidenced by significant tumor volume reduction in the hSFRP2 mAb-treated group, compared with controls (n = 10, p < 0.001). Likewise, Hs578T triple-negative breast tumors were smaller in the hSFRP2 mAb-treated group compared with controls (n = 10, p < 0.001). The hSFRP2 mAb treatment correlated with an increase in tumor cell apoptosis (n = 11, p < 0.05). Importantly, hSFRP2 mAb treatment was not associated with any weight loss or lethargy. We present a novel hSFRP2 mAb with therapeutic potential in breast cancer and sarcoma that has no effect on immunogenicity.

Efficacy of antibody-based therapies against Middle East respiratory syndrome coronavirus (MERS-CoV) in common marmosets

Cases of Middle East respiratory syndrome coronavirus (MERS-CoV) continue to be identified and with a lack of effective clinical treatment and no preventative strategies, treatment using convalescent plasma or monoclonal antibodies (mAbs) is a potential quick route to an intervention. Passive immunotherapy via either convalescent plasma or mAbs has proven to be effective for other infectious agents. Following infection with MERS-CoV, common marmosets were treated with high titer hyperimmune plasma or the mAb m336, at 6 and 48 h post inoculation. Both treatments reduced signs of clinical disease, but reduction in viral loads in the respiratory tract were only found in the hyperimmune plasma group. A decrease in gross pathology was found only in the mAb-treated group, but no histological differences were observed between treated and control animals. While both hyperimmune plasma and the m336 treatments reduced the severity of disease in the common marmoset, neither treatment resulted in full protection against disease.

Neutralizing anti-interleukin-1β antibodies reduce ischemia-related interleukin-1β transport across the blood–brain barrier in fetal sheep

Hypoxic ischemic insults predispose to perinatal brain injury. Pro-inflammatory cytokines are important in the evolution of this injury. Interleukin-1β (IL-1β) is a key mediator of inflammatory responses and elevated IL-1β levels in brain correlate with adverse neurodevelopmental outcomes after brain injury. Impaired blood–brain barrier (BBB) function represents an important component of hypoxic-ischemic brain injury in the fetus. In addition, ischemia–reperfusion increases cytokine transport across the BBB of the ovine fetus. Reducing pro-inflammatory cytokine entry into brain could represent a novel approach to attenuate ischemia-related brain injury. We hypothesized that infusions of neutralizing IL-1β monoclonal antibody (mAb) reduce IL-1β transport across the BBB after ischemia in the fetus. Fetal sheep were studied 24-h after 30-min of carotid artery occlusion. Fetuses were treated with placebo- or anti-IL-1β mAb intravenously 15-min and 4-h after ischemia. Ovine IL-1β protein expressed from IL-1β pGEX-2T vectors in Escherichia coli (E. coli) BL-21 cells was produced, purified, and radiolabeled with 125I. BBB permeability was quantified using the blood-to-brain transfer constant (Ki) with 125I-radiolabeled-IL-1β. Increases in anti-IL-1β mAb were observed in the brain of the mAb-treated group (P<0.001). Blood-to-brain transport of 125I-IL-1β was lower (P<0.04) across brain regions in the anti-IL-1β mAb-treated than placebo-treated ischemic fetuses. Plasma 125I-IL-1β counts were higher (P<0.001) in the anti-IL-1β mAb- than placebo-treated ischemic fetuses. Systemic infusions of anti-IL-1β mAb reduce IL-1β transport across the BBB after ischemia in the ovine fetus. Our findings suggest that conditions associated with increases in systemic pro-inflammatory cytokines and neurodevelopmental impairment could benefit from an anti-cytokine therapeutic strategy.

Anti-high mobility group box-1 monoclonal antibody treatment provides protection against influenza A virus (H1N1)-induced pneumonia in mice.

IntroductionProvision for the emergence of an influenza pandemic is an urgent issue. The discovery of a novel anti-influenza therapeutic approach would increase the effectiveness of traditional virus-based strategies. This study was undertaken to evaluate the therapeutic effects of anti-high mobility group box-1 (HMGB1) monoclonal antibody (mAb) treatment on influenza A virus (H1N1)-induced pneumonia in mice.MethodsNine-week-old male C57BL/6 mice were inoculated with H1N1, then anti-HMGB1 mAb or control mAb were administered intravenously at 1, 24 and 48 hours after H1N1 inoculation and the survival rate was analyzed. Lung lavage and histopathological analysis were performed on days 3, 5, 7 and 10 after inoculation.ResultsAnti-HMGB1 mAb significantly improved the survival rate of H1N1-inoculated mice (1 out of 15 versus 8 out of 15 deaths in the anti-HMGB1 mAb-treated group versus the control mAb-treated group, p < 0.01), although the treatment did not affect virus propagation in the lungs. The treatment also significantly attenuated histological changes and neutrophil infiltration in the lungs of H1N1-inoculated mice. This was associated with inhibition of HMGB1 and suppression of inflammatory cytokine/chemokine expression and oxidative stress enhancement, which were observed in H1N1-inoculated mice. The expression of receptor for advanced glycation end products and nuclear factor κB was attenuated by the treatment.ConclusionsAnti-HMGB1 mAb may provide a novel and effective pharmacological strategy for severe influenza virus infection in humans by reducing the inflammatory responses induced by HMGB1.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-015-0983-9) contains supplementary material, which is available to authorized users.

Anti-high mobility group box 1 antibody exerts neuroprotection in a rat model of Parkinson's disease

The high mobility group box-1 (HMGB1) exists as an architectural nuclear protein in the normal state, but displays an inflammatory cytokine-like activity in the extracellular space under pathological condition. Inflammation in the pathogenesis of Parkinson's disease (PD) has been documented. In this study, we investigated the involvement of HMGB1 in the pathology and the neuroprotective effects of neutralizing anti-HMGB1 monoclonal antibody (mAb) on an animal model of PD. Adult female Sprague–Dawley rats were initially injected with 6-hydroxydopmaine (6-OHDA, 20μg/4μl) into the right striatum, then anti-HMGB1 mAb (1mg/kg), or control mAb was intravenously administered immediately, at 6 and 24h after 6-OHDA injection. The treatment with anti-HMGB1 mAb significantly preserved dopaminergic neurons in substantia nigra pars compacta and dopaminergic terminals inherent in the striatum, and attenuated PD behavioral symptoms compared to the control mAb-treated group. HMGB1 was retained in the nucleus of neurons and astrocytes by inhibiting the proinflammation-induced oxidative stress in the anti-HMGB1 mAb-treated group, whereas HMGB1 translocation was observed in neurons at 1day and astrocytes at 7days after 6-OHDA injection in the control mAb-treated group. Anti-HMGB1 mAb inhibited the activation of microglia, disruption of blood–brain-barrier (BBB), and the expression of inflammation cytokines such as IL-1β and IL-6. These results suggested that HMGB1 released from neurons and astrocytes was at least partly involved in the mechanism and pathway of degeneration of dopaminergic neurons induced by 6-OHDA exposure. Intravenous administration of anti-HMGB1 mAb stands as a novel therapy for PD possibly acting through the suppression of neuroinflammation and the attenuation of disruption of BBB associated with the disease.

Abstract 4377: Biodistribution and therapeutic effects of a monoclonal antibody against Eph receptor A10 in a breast cancer xenograft model

Abstract Introduction HER2-targeting antibodies and anti-hormone drugs are effective agents for breast cancer patients. However, such treatments are not applicable to triple negative breast cancers (TNBCs) which don't express HER2, estrogen, and progesterone receptors. Thus, effective molecular targets for TNBC are urgently needed. In this respect, we searched for new targets using a proteomics approach and identified Eph receptor A10 (EphA10) to be highly expressed in breast cancer including TNBCs, compared with normal breast tissues. Moreover, we previously found that EphA10 is expressed in testis but not in other normal tissues, thus suggesting that EphA10 could become a promising therapeutic target in breast cancer patients. Here, we developed a novel monoclonal antibody (mAb) against EphA10 and showed that it accumulates in the tumor and has anti-tumor properties in a breast cancer xenograft model. Materials and Methods Characterization of the anti-EphA10 mAb; Specificity of the mAb was evaluated by mAb binding to EphA family proteins (EphA1-A8, A10). Affinity of the mAb was analyzed by surface plasmon resonance method. Tumor accumulation analysis of anti-EphA10 mAb; Alexa647-conjugated anti-EphA10 mAb or control mAb were administrated intravenously and observed daily using an in vivo imaging system. Anti-EphA10 mAb treatment in a mouse xenograft model; A mouse model was generated by orthotopic transplantation of EphA10 expressing MDA-MB-435 (TNBC) cells. When the tumor size reached approximately a volume of 100 mm3, anti-EphA10 mAb and control mAb were administrated intraperitoneally twice a week. Results and Discussion The results showed that the anti-EphA10 mAb had an affinity for EphA10 in the nanomolar range. Moreover, the mAb specifically bound to EphA10 but not to the other EphA family proteins; therefore, our mAb had the same specificity and affinity for EphA10 as other existing antibody drugs. Furthermore, the mAb also displayed cross-reactivity with mouse EphA10, suggesting that we could evaluate the mAb in a mouse model. The administration of the fluorescein-labeled mAb to the mice bearing EphA10-positive breast tumors showed that the anti-EphA10 mAb accumulated in the tumors to a greater extent than the control mAb and tended to be restricted to the tumor. Furthermore, tumor growth was significantly suppressed in the mAb-treated mice in a dose-dependent manner. On the other hand, body weight and biochemical markers of tissue damage did not change between the mAb or control mAb-treated groups. These data indicate that our mAb might become a promising therapeutic tool for treating EphA10-positive breast cancers. Conclusion Our anti-EphA10 mAb mainly accumulated in EphA10-positive tumor cells and showed anti-tumor effects. We believe that these findings will contribute to the development of a novel drug in the treatment of breast cancer patients refractory to traditional therapies. Citation Format: Kazuya Nagano, Yuka Maeda, Takuya Yamashita, Yohei Mukai, Haruhiko Kamada, Kazuma Higashisaka, Yasuo Yoshioka, Yasuo Tsutsumi, Shin-ichi Tsunoda. Biodistribution and therapeutic effects of a monoclonal antibody against Eph receptor A10 in a breast cancer xenograft model. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4377. doi:10.1158/1538-7445.AM2015-4377

Five-year survival and costs of care in metastatic colorectal cancer: conventional versus monoclonal antibody-based treatment protocols

Aim: To evaluate the costs and survival estimates of metastatic colorectal carcinoma patients treated with conventional cytostatic protocols and adjuvant monoclonal antibodies (mAbs). Methods: Retrospective randomized case series and cost-of-illness analysis was used. Metastatic colorectal carcinoma cases (62) were randomly selected from the archive of the largest university military hospital in Southeastern Europe. Results: A 6-month longer survival was attributed to mAbs (p = 0.581). Conventional protocols incurred €5137 (95% CI: €3758–€6517) versus €22,113 (95% CI: €16,201–€28,025) total direct medical costs in mAb-based group. ICER of €32,108 per life year gained attributable to mAbs three-fold exceeded informal willingness to pay threshold of Serbia. Conclusion: mAbs adjuvant protocols had modest positive impact on 5-year survival rates. Costs were driven by targeted biologicals, but significantly higher costs of care were recorded in mAb-treated group in other domains, as well. More selective prescription and reimbursement criteria should be applied to increase cost–effectiveness of targeted oncology agents.

MAb therapy against the IFN-α/β receptor subunit 1 stimulates arteriogenesis in a murine hindlimb ischaemia model without enhancing atherosclerotic burden.

IFN-beta (IFNβ) signalling is increased in patients with insufficient coronary collateral growth (i.e. arteriogenesis) and IFNβ hampers arteriogenesis in mice. A downside of most pro-arteriogenic agents investigated in the past has been their pro-atherosclerotic properties, rendering them unsuitable for therapeutic application. Interestingly, type I IFNs have also been identified as pro-atherosclerotic cytokines and IFNβ treatment increases plaque formation and accumulation of macrophages. We therefore hypothesized that mAb therapy to inhibit IFNβ signalling would stimulate arteriogenesis and simultaneously attenuate-rather than aggravate-atherosclerosis. In a murine hindlimb ischaemia model, atherosclerotic low-density lipoprotein receptor knockout (LDLR(-/-)) mice were treated during a 4-week period with blocking MAbs specific for mouse IFN-α/β receptor subunit 1 (IFNAR1) or murine IgG isotype as a control. The arteriogenic response was quantified using laser Doppler perfusion imaging (LDPI) as well as immunohistochemistry. Effects on atherosclerosis were determined by quantification of plaque area and analysis of plaque composition. Downstream targets of IFNβ were assessed by real-time PCR (RT-PCR) in the aortic arch. Hindlimb perfusion restoration after femoral artery ligation was improved in mice treated with anti-IFNAR1 compared with controls as assessed by LDPI. This was accompanied by a decrease in CXCL10 expression in the IFNAR1 MAb-treated group. Anti-IFNAR1 treatment reduced plaque apoptosis without affecting total plaque area or other general plaque composition parameters. Results were confirmed in a short-term model and in apolipoprotein E knockout (APOE)(-/-) mice. Monoclonal anti-IFNAR1 therapy during a 4-week treatment period stimulates collateral artery growth in mice and did not enhance atherosclerotic burden. This is the first reported successful strategy using MAbs to stimulate arteriogenesis.

Axl Receptor Blockade Ameliorates Pulmonary Pathology Resulting from Primary Viral Infection and Viral Exacerbation of Asthma

Viruses use Tyro3, Axl, and Mertk (TAM) receptor tyrosine kinases to infect and modulate the immune properties of various cell types, which led us to investigate whether TAM receptor activation affected primary viral infection and viral exacerbation of asthma in experimental models. In these lung-specific models, we observed that Axl was the most abundantly induced TAM receptor protein. During primary respiratory syncytial virus (RSV) infection, anti-Axl mAb treatment significantly increased the number of IFN-γ-producing T cells and NK cells and significantly suppressed RSV replication and whole lung levels of IL-4 and IL-13. Intrapulmonary H1N1 infection induced lethal pulmonary inflammation, but anti-Axl mAb treatment of infected mice significantly increased the number of IFN-β-producing macrophages and dendritic cells and significantly suppressed neutrophil infiltration. Consequently, the lethal effect of H1N1 infection in this model was significantly reduced in the mAb-treated group compared with the IgG control-treated group. Targeting Axl also inhibited airway hyperresponsiveness, IL-4 and IL-13 production, and goblet cell metaplasia in an Aspergillus fumigatus-induced asthma model. Finally, infection of mice with RSV during fungal asthma significantly exacerbated airway inflammation, goblet cell metaplasia, and airway remodeling, but all of these features in this viral exacerbation model were ameliorated by anti-Axl mAb treatment. Taken together, these results demonstrate that Axl modulates the pulmonary immune response during viral and/or allergic pathology, and they also suggest that targeting this TAM receptor might provide a novel therapeutic approach in these infectious diseases.

Anti-ST2 monoclonal antibody inhibits eosinophil infiltration in Angiostrongylus cantonensis-infected mice

Interleukin-33 (IL-33) could play an important role in the pathogenesis of angiostrongylosis. However, the role of IL-33/ST2 pathway in this parasitic infection is uncertain. C57BL/six mice were each infected with 35 Angiostrongylus cantonensis larvae. One group of mice received an intraperitoneal injection of anti-ST2 monoclonal antibody (mAb; 50μg) 3 days postinfection and subsequent booster shots of the same dose at 5-day intervals. Blood samples from each group were collected every week for assays. The level of IL-5 significantly decreased in the mAb-treated group, and the infiltration of eosinophils in the meninges was also significantly reduced. The IL-33/ST2 axis may play a crucial role in the pathogenesis of angiostrongylosis and the results of this study could be useful for the development of strategies to reduce the neurological damage caused by this parasitic infection.

IL-33 mediates the expressions of IL-5 and IL-13 in Angiostrongylus cantonensis-infected mice

Angiostrongylus cantonensis is the major cause of human eosinophilic meningoencephalitis. C57BL/6 mice were experimentally infected with 35 infectious larvae. Two groups of infected mice received intraperitoneal injections of mouse IL-33 (1μg) or anti-IL-33 monoclonal antibody (mAb) (10μg) 3days post infection (dpi) and subsequent booster shots of the same dose at 5day intervals. Blood samples from each group were collected weekly for assays. IgE levels were significantly increased in all infected mice. The eosinophil percentage and levels of IL-5 and IL-13 significantly increased in the IL-33-treated group relative to infected but non-treated animals. The level of IL-5 decreased in the mAb-treated group. The severity of eosinophilic meningitis was exacerbated in the IL-33 injected group. Taken together, these results suggest that IL-33 mediates the expressions of IL-5 and IL-13, and plays a crucial role in the pathogenesis of angiostrongylosis.

Effect of Inhibiting Interleukin‐1β with Neutralizing Antibody on Tight Junction Protein Expression after Brain Ischemia in Ovine Fetus

We tested the hypothesis that inhibiting interleukin-1β (IL-1β) with neutralizing monoclonal antibody (mAb) alters tight junction (TJ) protein expression after brain ischemia-reperfusion (I/R) in the ovine fetus. Ovine fetuses at 85% gestation were studied after 30 min of ischemia and 24 h of reperfusion. Ovine IL-1β mAb has been generated, and showed high sensitivity, specificity, and neutralizing effects to IL-1β protein in vitro. Intravenous placebo (PL) or IL-1β mAb (5 mg/kg) infusions were given to the fetuses 15 min and 4 h after brain ischemia. Occludin (Occl), claudin-1 (CL-1), and CL-5 protein expression were determined by Western immunoblot in non-ischemic (sham, n=5), I/R+PL (n=6), and I/R+IL-1β mAb-treated (n=7) groups in the cerebral cortex, caudate nucleus, cerebellum, and medulla. Results are expressed as ratio to an internal control protein. In the medulla, Occl expression decreased and CL-5 expression increased after I/R+IL-1β mAb treatment compared to the sham group (Fig., M ± SD, P<0.05), but CL-1 expression did not change. Similar patterns of TJ expression were not observed in the cerebral cortex, cerebellum or caudate nucleus (data not shown). Treatment with IL-1β mAb affects I/R-related transmembrane TJ protein expression in some, but not all brain regions studied. Alterations in BBB function after I/R and IL-1β mAb treatment may not be directly regulated by changes in transmembrane TJ proteins in the fetus. NIH-HD-057100

Monoclonal antibody to intercellular adhesion molecule-1 as a novel therapy for preeclampsia: preliminary results from a rat model

Objective: Preeclampsia is a prevalent and potentially devastating complication of pregnancy. Intercellular adhesion molecule-1 (ICAM-1) was reported to be involved in the pathogenesis of the disease. Therefore we hypothesized anti-ICAM-1 monoclonal antibody (mAb) could be a therapeutic choice for preeclampsia. The objective of this study was to evaluate its therapeutic effects using a rat model of preeclampsia. Methods: Timed pregnant Wistar rats were intravenously injected endotoxin and then randomized to receive either anti-ICAM-1 mAb or saline. The effects of antibody on blood pressure, urinary protein, levels of alanine aminotransferase (ALT), blood urea nitrogen (BUN), creatinine, uric acid, weight of placenta were measured. Pregnancy outcomes were evaluated. Results: Anti-ICAM-1 mAb significantly decreased the levels of blood pressure, urinary protein, maternal BUN, creatnine and uric acid comparing with untreated preeclamptic rats. And the antibody therapy significantly improved pregnancy outcomes. After five days of mAb treatment, most of the parameters in mAb-treated group approached normal levels. Conclusions: Our data prove anti-ICAM-1 mAb therapy as a promising choice for preeclampsia.

Anti-CCR3 monoclonal antibody inhibits eosinophil infiltration in Angiostrongylus cantonensis-infected ICR mice

ICR mice were each infected with 35 Angiostrongylus cantonensis larvae. One group of mice received an intraperitoneal injection of anti-CCR3 monoclonal antibody (mAb) (50 microg) at 10 days post-infection (dpi), while another similarly-treated group also received a booster injection (25 microg) at 12 dpi. All the mice were sacrificed at 14 dpi for pathological examination, enzyme-linked immunosorbent assay analysis and RNA extraction. The infiltration of eosinophils and the severity of eosinophilic meningitis were reduced in both the mAb-treated groups, relative to infected but untreated animals. The levels of CCL11 (eotaxin) in the peripheral circulation and the expression of the Th2-type cytokine interleukin-5 in the brains were significantly reduced. A. cantonensis infection is the major cause of eosinophilic meningoencephalitis in Taiwan, and the results of this study could be useful for the development of strategies to reduce the neurological damage caused by this infection.

Systemic treatment of anti‐CD4+CD25+ T cell monoclonal antibody exacerbates sialoadenitis in submandibular glands during the early life in lupus‐prone female NZB × NZWF1 mice

The maintenance mechanisms of peripheral tolerance by CD4(+)CD25(+) T cells before the development of sialoadenitis in secondary Sjögren's syndrome (sSS) are not well understood. The aim of the present study is to examine the effect of reduction of CD4(+)CD25(+) T cells on the development of sialoadenitis during the early life in female NZB x NZWF(1) (B/WF(1)) mice, a model for human sSS. Female B/WF(1) mice at 3 days after birth were treated with either anti-mouse CD4(+)CD25(+) T cells rat IgG(1) monoclonal antibody (mAb) or Rat IgG(1)(control). At 25 weeks of age, autoantibodies against nucleus and cytoplasm of ductal epithelial and myoepithelial cells, and histpathology of submandibular glands were examined in the mAb-treated and control groups. Also the development of anti-Ro/SS-A antibodies was examined until 25 weeks of age in both groups. The mAb-treated group showed severe lesions with the development of autoantibodies compared to the control group. The present results suggest that peripheral CD4(+)CD25(+) T cells may, at least in part, contribute to down-regulate the development of sialoadenitis in submandibular glands of lupus-prone female B/WF(1) mice during their early life.

Amelioration of Mercury-Induced Autoimmunity by 4-1BB

In certain strains of mice, subtoxic doses of HgCl2 (mercuric chloride; mercury) induce a complex autoimmune condition characterized by the production of antinucleolar IgG Abs, lymphoproliferation, increased serum levels of IgG1/IgE Abs, and deposition of renal immune complexes. 4-1BB is an important T cell costimulatory molecule that has been implicated in T cell proliferation and cytokine production, especially production of IFN-gamma. To elucidate T cell control mediated by the 4-1BB signaling pathway in this syndrome, we assessed the effect of administering agonistic anti-4-1BB mAb on mercury-induced autoimmunity. Groups of A.SW mice (H-2s) received mercury/control Ig or mercury/anti-4-1BB or PBS alone. Anti-4-1BB mAb treatment resulted in a dramatic reduction of mercury-induced antinucleolar Ab titers, serum IgG1/IgE induction, and renal Ig deposition. These effects may be related to the present finding that anti-4-1BB mAb decreases B cell numbers and function. The anti-4-1BB mAb-treated mercury group also showed a marked reduction in Th2-type cytokines but an increase in Th1-type cytokines and chemokines. Increased IFN-gamma production due to anti-4-1BB mAb treatment appears to be responsible for the observed B cell defects because neutralization of IFN-gamma in vivo substantially restored B cell numbers and partly restored IgG1/IgE. Collectively, our results indicate that 4-1BB mAb can down-regulate mercury-induced autoimmunity by affecting B cell function in an IFN-gamma-dependent manner and thus, preventing the development of autoantibody production and tissue Ig deposition.