Ligation of human Fc receptor like-2 (FCRL2) by monoclonal antibodies downregulates B cell receptor mediated signaling

B cell antigen receptor (BCR) signaling and its regulation through negative and positive regulators are critical for balancing B cell response and function. Human Fc receptor like-2 (FCRL2), a member of the newly identified FCRL family, could influence B cell signaling due to possession of both immunoreceptor tyrosine-based activation and inhibitory motifs (ITAM and ITIM). Since the natural ligand of FCRL2 has not been identified yet, we generated FCRL2-specific monoclonal antibodies (mAbs) and employed them to investigate the influence of FCRL2 stimulation on BCR signaling in a FCRL2-expressing B cell line. Two anti-FCRL2 mAb-producing hybridoma clones (5A7-E7 and 3D8-G8) were selected. None of the mAbs displayed any cross-reactivity with the other members of the FCRL family including recombinant FCRL1, 3, 4 and 5, as tested by FACS and ELISA techniques. Engagement of the FCRL2 by these mAbs resulted in significant inhibition of BCR signaling mediators such as calcium mobilization and phosphorylation of the MAP kinases Erk, p38 and Jnk MAP. These findings indicate that the FCRL2 ITIM motifs are functional and the anti-FCRL2 mAbs may mimic the natural ligand of FCRL2 by induction of inhibitory signals in B cells.Food and Drug Administration of the Ministry of Health, Treatment and Medical Education of Iran (grant number S87P/3/414). MS was also supported by EFIS-IL fellowship grant.Accepte

The Suppression of Adjuvant-induced Inflammation and the Inhibition of the Serum and Tissue IL-17, TNF-α and IL-1β levels by Thymol and Carvacrol

Background and Aim: Thymol and carvacrol are two important components of thyme that have multiple medicinal uses. This study investigates the in vivo effects of these natural products on adjuvant-induced inflammation and secretion of interleukin (IL)-17 and key inflammatory cytokines in rats. Materials and Methods: We injected complete Freund’s adjuvant (CFA) into the hind paws of rats in order to induce inflammation. Each of the CFA-treated rat groups received gavages of thymol, carvacrol, or vehicle (CFA-only group). Rats’ paws and ankle edema were measured and then we were able to determine an inflammatory score based on the results. After 72 h of inflammation induction, sera were collected and subsequently inflamed tissue extracts were prepared for cytokine assay by ELISA. Results: Both components significantly decreased paw edema in rats (p<0.01). Thymol decreased ankle edema to 61.6% of edema in CFA-only rats (p<0.001). We observed a decreased inflammatory score in the thymol and carvacrol-treated rats. The evaluation of the tissue and serum inflammatory cytokine levels showed that both components decreased tumor necrosis factor (TNF)-α levels (p<0.05). Thymol and carvacrol reduced interleukin (IL)-1β serum and tissue levels, respectively. These components reduced tissue levels of IL-17 from 148.4±13.4pg/ml in CFA-only rats to 90.1±18.9pg/ml (thymol) and 82.3±9.2pg/ml (carvacrol). Both components decreased serum IL-17 levels in rats (p<0.05). In comparison, the anti-inflammatory drug, indomethacin, reduced the inflammatory score and decreased tissue TNF-α and IL-1β levels but did not affect IL-17 production. Conclusion: Carvacrol and thymol could relieve inflammation symptoms possibly by downregulating serum and tissue IL-17 expression in addition to key pro-inflammatory cytokines, TNFα and IL-1β

Final 3.indd

Abstract Background: The possible prognostic signi¿cance of the expression of a variety of markers has been investigated in acute lymphoblastic leukemia (ALL). Methods: In the present study we investigated the prognostic signi¿cance of CD13 and CD33 myeloid antigens (MY) aberrantly expressed on the blasts of ALL patients and Bcl-2 anti-apoptotic molecule expression in childhood ALL. Results: Aberrant expression of MY occurred in 8.8% of cases. Variant levels of Bcl-2 were expressed in patients (44.2±25.5%), with more than 20% positivity for Bcl-2 in 64.7% of patients. Bcl-2 + patients survived 959±242 days compared to 1059+230 days for Bcl-2 -patients (P=0.2). Corresponding data for complete remission duration was 682±170 and 716±173 days (P=0.3), respectively, indicating no signi¿cant association between survival and complete remission duration of patients with expression of the Bcl-2 molecule. Analysis of clinical response according to MY expression, however, showed signi¿cant association with survival and complete remission duration. MY + patients had shorter complete remission duration (383±58 days) and survival (473±68 days) than MY -patients (complete remission duration, 724±144 days; survival, 1045±186 days; P&lt;0.001). Expression of Bcl-2 along with MY was not associated with a signi¿cant decrease in survival or complete remission duration. Conclusion: Results of this study indicated that expression of MY was a poor prognostic factor in childhood ALL. Bcl-2 expression in MY + patients could not inÀuence the response to therapy

Anti–oxidative and anti–inflammatory effects of Tagetes minuta essential oil in activated macrophages

Objective: To investigate antioxidant and anti-inflammatory effects of Tagetes minuta (T. minuta) essential oil. Methods: In the present study T. minuta essential oil was obtained from leaves of T. minuta via hydro-distillation and then was analyzed by gas chromatography-mass spectrometry. The anti-oxidant capacity of T. minuta essential oil was examined by measuring reactive oxygen, reactive nitrogen species and hydrogen peroxide scavenging. The anti-inflammatory activity of T. minuta essential oil was determined through measuring NADH oxidase, inducible nitric oxide synthase and TNF-α mRNA expression in lipopolysacharide-stimulated murine macrophages using real-time PCR. Results: Gas chromatography-mass spectrometry analysis indicated that the main components in the T. minuta essential oil were dihydrotagetone (33.86%), E-ocimene (19.92%), tagetone (16.15%), cis-β-ocimene (7.94%), Z-ocimene (5.27%), limonene (3.1%) and epoxyocimene (2.03%). The T. minuta essential oil had the ability to scavenge all reactive oxygen/reactive nitrogen species radicals with IC50 12-15 μg/mL, which indicated a potent radical scavenging activity. In addition, T. minuta essential oil significantly reduced NADH oxidase, inducible nitric oxide synthaseand TNF-α mRNA expression in the cells at concentrations of 50 μg/mL, indicating a capacity of this product to potentially modulate/diminish immune responses. Conclusions: T. minuta essential oil has radical scavenging and anti-inflammatory activities and could potentially be used as a safe effective source of natural anti-oxidants in therapy against oxidative damage and stress associated with some inflammatory conditions

Chemical composition, radical scavenging and anti-oxidant capacity of <i>Ocimum Basilicum</i> essential oil

<p><i>Ocimum basilicum</i> has several functional characteristics including carminative, stimulant, diuretic, antiseptic, anesthetic, anti-spasmodic, analgesic and anti-tussive properties. <i>O. basilicum</i> essential oil (basil oil) was tested for chemical composition and in vitro and ex vivo anti-oxidant activities. The in vitro anti-oxidant capacity of basil oil was examined using 1, 1-diphenyl-2-picryl-hudrazyl radical (DPPH^•), 2, 2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) radical (ABTS^•), hydrogen peroxide (H₂O₂), hydroxyl radical (HO^•), nitric oxide (NO) and nitrite (NO₂) scavenging effects. The <i>ex vivo</i> anti-oxidant activity of basil oil was determined through measuring NADH oxidase (NOX) and inducible nitric oxide synthase (iNOS) mRNA expression in lipopolysaccharide-stimulated murine macrophages using real-time polymerase chain reaction (RT-PCR). GC-MS analysis indicated that the main components in the basil oil were methylchavicol (47%), geranial (19%) and neral (15%). Basil oil had effective DPPH^•, ABTS^•, H₂O₂, HO^•, NO and NO₂ scavenging effects. Basil oil significantly reduced NOX and iNOS mRNA expression in lipopolysaccharide-stimulated murine macrophages at concentrations of 1-10 μg/mL. Basil oil had radical scavenging and anti-oxidant activities and could potentially be used as a safe and effective source of natural anti-oxidants in therapy against oxidative damage and stress associated with some inflammatory conditions.</p

Design and Synthesis of Gatekeeper Coated Dendritic Silica/Titania Mesoporous Nanoparticles with Sustained and Controlled Drug Release Properties for Targeted Synergetic Chemo-Sonodynamic Therapy

New dendritic silica/titania mesoporous nanoparticles (DSTNs) loaded with curcumin (CUR) were synthesized and coated with polyethylenimine-folic acid groups (PEI-FA) for an ultrasound (US)-triggered drug release and combined chemo-sonodynamic therapy. The PEI-FA groups play a gatekeeper role, strongly encapsulate the CUR molecules inside the nanocarrier, and prevent the unwanted premature release by blocking the mesoporous channels. The results showed that the specific cancer cell uptake is improved by FA groups on the surfaces of DSTNs via receptor-mediated endocytosis. The TiO2 layer as a sonosensitizer agent coated on the mesoporous silica nanoparticles generates reactive oxygen species. Following the US irradiation, the PEI molecules were cut off by free radicals, including OH center dot and O-2(-), on the exterior surface of DSTNs, and the CUR loaded in the nanocarrier was then released into the cancer cell cytosol. The release profiles of the CUR@PEI-FA-DSTN system showed that the amount of CUR released from DSTNs is controlled by tuning the US radiation time. The results of the MTT cytotoxicity tests of free CUR, free PEI-FADSTN nanocarrier, and CUR@PEI-FA-DSTNs against A549 (human lung carcinoma cell lines) and HeLa (human cervical carcinoma cell lines ( showed that the toxicity of CUR@PEI-FA-DSTNs is higher than those of CUR and PEI-FA-DSTNs alone. In addition, the specific targeting ability, the cellular uptake, and the anticancer activity of the synthesized compounds for targeted cancer treatment were investigated using different staining methods and fluorescence microscopy. The results revealed that the new system, CUR@PEI-FA-DSTNs, can be considered as a potent drug delivery system for increasing effectiveness of the anticancer activity of curcumin in the combined chemo-sonodynamic therapy

Modulation of Cytokine Production and Transcription Factors Activities in Human Jurkat T Cells by Thymol and Carvacrol

Purpose: Thymol and carvacrol, two main components of thyme, have shown anti-inflammatory effects. The aim of this study was to assess the effects of these components on Jurkat leukemia cells as an in vitro T cell model and their molecular mechanisms of activity. Methods: Cells were cultured in the presence of components and subsequently stimulated with phorbol-12-myristate-13-acetate (PMA)/calcium ionophore for evaluating interleukin (IL)-2 and interferon (IFN)-γ production. The activation of T cell transcription factors that included nuclear factors of activated T cells (NFATs), activator protein-1 (AP-1; c-Jun/c-Fos), and nuclear factor (NF)-KB were examined by Western blot analysis. Results: Thymol and carvacrol at 25 µg/ml significantly reduced IL-2 levels from 119.4 ± 8pg/ml in control cells treated only with PMA/Calcium ionophore and the solvent to 66.9 ± 6.4pg/ml (thymol) and 32.3 ± 3.6pg/ml (carvacrol) and IFN-γ from 423.7 ± 19.7pg/ml in control cells to 311.9 ± 11.6pg/ml (thymol) and 293.5 ± 16.7pg/ml (carvacrol). Western blot analyses of nuclear extracts showed that the same concentrations of components significantly reduced NFAT-2 to 44.2 ± 2.7% (thymol) and 91.4 ± 2.3% (carvacrol) of the control (p<0.05), and c-Fos to 31.2 ± 6.2% (thymol) and 27.6 ± 3.1% (carvacrol) of the control (p<0.01). No effects on NFAT-1, c-Jun and phospho-NF-KBp65 levels were observed. Conclusion: Thymol and carvacrol could contribute to modulation of T cell activity by reducing IL-2 and IFN-γ production possibly through down regulation of AP-1 and NFAT-2 transcription factors suggesting their potential usefulness for reduction of T cell overactivity in immune-mediated diseases

Dihydropyridine derivatives to overcome atypical multidrug resistance : design, synthesis, QSAR studies, and evaluation of their cytotoxic and pharmacological activities

Multidrug resistance (MDR) is defined as resistance of tumor cells to the cytotoxic action of multiple structurally dissimilar and functionally divergent drugs commonly used in chemotherapy. Until now, there is no evidence for the effect of 1,4-dihydropyridines (DHPs) on atypical MDR, although there are some indications about the effect of DHPs on p-glycoprotein-mediated MDR. However, it was reported that a DHP derivative (Dexniguldipine) inhibited human DNA topoisomerase I through a non-competitive mechanism. Therefore, some derivatives of DHP were synthesized and their effect in reversing atypical MDR was evaluated. The results showed that two compounds were the potent reversals of atypical MDR. In addition, the intrinsic cytotoxicity of compounds was determined on four different cell lines. Furthermore, their Ca2+ channel blocking activity was evaluated and showed a clear structure-activity relationship (SAR) trend according to the moieties in C-4 position which confirmed the importance of C-4 moiety on Ca2+ channel blocking

Cytotoxic effect of some 1,4-dihydropyridine derivatives containing nitroimidazole moiety

The 1,4-dihydropyridine (DHP) derivatives are a known class of calcium channel blockers. Some derivatives of DHP showed significant cytotoxicity. It was shown that this effect may not be the result of interaction with Ca2+ channels. In this study, we performed an investigation about the intrinsic cytotoxicity of some derivatives of DHP containing nitroimidazole moiety on their C4 position on four different cancer cell lines (Raji, K562, Fen and HeLa). The result showed that these compounds had moderate-good cytotoxic activity. In addition, QSAR model shows the importance of N atom in cytotoxicity; Ca2+ channels