Anti-TNF alpha therapy in rheumatoid arthritis--current and future directions.
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Antibodies, Monoclonal↗
Biomedical subjects
R O Williams
Publications and source records attributed to R O Williams.
Paradoxical effects of adenovirus-mediated blockade of TNF activity in murine collagen-induced arthritis.
Collagen-induced arthritis (CIA) is an experimental model of arthritis widely used to dissect the pathogenesis of human rheumatoid arthritis and to identify potential therapeutic targets. Among these, TNF-alpha has been recognized to play an important role. Here we investigate the feasibility and therapeutic efficacy of prolonged blockade of TNF-alpha activity through the adenovirus-mediated gene delivery of a dimeric chimeric human p55 TNFR-IgG fusion protein and compare it to protein therapy in established CIA. A single i.v. administration of the replication-deficient adenovirus yielded microgram serum levels of the chimeric fusion protein and ameliorated CIA for 10 days. Subsequently, benefit was lost and a rebound to greater inflammatory activity was observed despite the continual presence of bioactive TNFR fusion protein. A similar trend was also observed in mice injected directly with comparable amounts of a human TNFR-IgG fusion protein, whereas the administration of a control adenovirus-encoding beta-galactosidase or of a control human IgG1 protein did not significantly affect the disease course. The mechanisms of the rebound of CIA were investigated, and augmented Ab response to collagen type II and TNFR were identified as potential causes. Our results confirm the feasibility of adenovirus-mediated gene delivery of cytokine inhibitors in animal models of autoimmune diseases for investigational purposes and highlight the importance of prolonged studies. Further investigations are needed to optimize ways of exploiting the potential of adenoviral gene therapy in RA.
Abatacept↗
Amelioration of collagen-induced arthritis and suppression of interferon-gamma, interleukin-12, and tumor necrosis factor alpha production by interferon-beta gene therapy.
OBJECTIVE: To investigate the therapeutic effects and possible mechanisms of action of constitutive expression of interferon-beta (IFNbeta) by syngeneic fibroblasts from DBA/1 mice in the collagen-induced arthritis (CIA) model. METHODS: Immortalized embryonic DBA/1 fibroblasts were infected with a retrovirus expressing murine IFNbeta. IFNbeta-expressing fibroblasts were then implanted intraperitoneally into mice immunized with bovine type II collagen. The effect of IFNbeta on paw swelling, anticollagen antibody levels, IgG1/IgG2a isotype profiles, arthritis score, histologic joint damage, and cytokine secretion from lymph node cells and from bone marrow-derived macrophages was assessed. RESULTS: A single injection of IFNbeta-secreting fibroblasts was sufficient to prevent arthritis or to ameliorate existing disease. Thus, IFNbeta reduced the clinical score and paw swelling irrespective of whether the injection was administered before or after disease onset in treated mice, compared with that in the untreated control group (P < 0.05). Histologic findings in the IFNbeta-treated mice were markedly less severe than in the control group (P < 0.001). This effect was accompanied by a decrease in total anticollagen IgG levels, a decrease in anticollagen IgG2a, and an increase in IgG1. In vitro, supernatants from these engineered fibroblasts inhibited collagen-induced interferon-gamma secretion from lymph node cells, and reduced the levels of tumor necrosis factor alpha and interleukin-12 produced by lipopolysaccharide/IFNgamma-treated bone marrow-derived macrophages. This effect was specific, since it was reversed with anti-IFNbeta polyclonal antibodies. CONCLUSION: These results indicate that IFNbeta, which is currently used as a treatment for relapsing, remitting multiple sclerosis, is a potent immunomodulatory and antiinflammatory cytokine in CIA and should be considered for the treatment of rheumatoid arthritis.
Animals↗
CD44 involvement in experimental collagen-induced arthritis (CIA).
CD44 is a pro-inflammatory cell surface molecule that supports cell migration and cell lodgment in target organs. Therefore, CD44 targeting with specific monoclonal antibodies (mAbs) should be useful for the inhibition of collagen-induced arthritis (CIA) as well as other autoimmune diseases that are dependent on inflammatory cells. In the present paper, we confirm and expand previous reports showing the anti-arthritogenic effect of anti-CD44 mAbs directed against constant epitopes of the CD44 receptor. We demonstrate that such anti-CD44 mAbs can induce resistance to CIA after disease onset. Even accelerated disease developed after two injections of type II collagen was markedly inhibited by IM7.8.1 anti-CD44 mAb. Although KM81 anti-CD44 mAb is a less efficient anti-arthritogenic reagent than IM7.8.1, its Fab' fragments partially inhibit CIA. This finding implies that the antibody blocks CD44 function rather than modulating CD44 cell surface expression or mediating Fc-dependent activities. Histopathological analysis revealed that the anti-CD44 mAb markedly reduces the synovial inflammatory cellular response and the consequent damage to the joint. As CD44 is an alternatively spliced multistructural molecule, similar anti-arthritogenic effects may be achieved by mAbs directed against CD44 isoforms expressed on the pathological cells in question, but not on normal cells, thus leaving the physiological functions intact.
Animals↗
Formulation of a protein with propellant HFA 134a for aerosol delivery.
The purpose of this study was to investigate the formulation and delivery of a protein in a pressurized metered-dose inhaler (pMDI) containing HFA 134a as the propellant for aerosol delivery. Ethanol and surfactants, including polyoxyethylene 10 oleyl ether (Brij 97), polyoxyethylene 20 oleyl ether (Brij 98), polyoxyethylene sorbitan monooleate (Tween 80) and Aerosol OT (AOT), were investigated as formulation adjuvants to improve the dose delivery characteristics of the model protein (bovine serum albumin) containing pMDI formulations. The aqueous solution of a surfactant and protein was lyophilized to obtain a solid carrier system of the protein. Readily dispersible suspensions were obtained by suspending this solid carrier system in HFA 134a with ethanol as a dispersing aid. The formulations containing Tween 80 resulted in the highest respirable fraction. This study suggested a potential formulation containing a lyophilized complex of surfactant and protein readily dispersible in HFA 134a for delivering a therapeutic protein to the respiratory tract by inhalation.
Aerosols↗
Influence of formulation technique for hydroxypropyl-beta-cyclodextrin on the stability of aspirin in HFA 134a.
The objective of this study was to determine the influence of the formulation technique for 2-hydroxypropyl-beta-cyclodextrin (HP beta CD) on the stability of aspirin in a suspension-based pressurized metered-dose inhaler (pMDI) formulation containing a hydrofluoroalkane (HFA) propellant. HP beta CD was formulated in a pMDI as a lyophilized inclusion complex or a physical mixture with aspirin. A pMDI formulation containing aspirin alone was used as the control. The chemical stability of aspirin in each pMDI formulation was determined over 6-months storage at 5, 25 and 40 degrees C. The quantity of water taken up into the pMDI canister was determined by Karl Fisher titration after storage for 6 months. Differential scanning calorimetry (DSC) was used to confirm the formation of a complex between HP beta CD and aspirin. Aspirin in the lyophilized inclusion complex exhibited the most significant degree of degradation during the 6-months storage, while aspirin alone in the pMDI demonstrated a moderate degree of degradation. Aspirin formulated in the physical mixture displayed the least degree of degradation. The water uptake study showed that water ingress occurred to the greatest extent for formulations containing aspirin and HP beta CD physical mixture, and to the least extent for formulations containing aspirin alone. Finally, the DSC study indicated that an inclusion complex was formed in situ in the pMDI formulations containing the HP beta CD and aspirin physical mixture. In conclusion, HP beta CD may be used to enhance the stability of a chemically labile drug, but the drug stability may be affected by the method of preparation of the formulation.
2-Hydroxypropyl-beta-cyclodextrin↗
Application of co-grinding to formulate a model pMDI suspension.
The objective of this study was to investigate the effect of co-grinding the model drug, triamcinolone acetonide (TAA), with a polymeric surfactant on the in vitro performance of a model pMDI suspension system. The physicochemical properties of TAA after co-grinding with the surfactant, Pluronic F77, were determined by laser light diffraction, helium pycnometry and equilibrium solubility measurements. TAA-surfactant interaction was investigated by differential scanning calorimetry and Fourier transform infrared spectroscopy (FTIR). The suspension characteristics of pMDI formulations prepared with co-ground TAA and surfactant were investigated by determining their in situ sedimentation, rheological profiles and vapor pressure. The performance characteristics of the pMDI formulations were determined by cascade impaction and dose delivery through-the-valve (DDV) measurements. It was found that the presence of Pluronic F77 decreased the solubility of TAA in the propellant medium. Co-grinding TAA particles with Pluronic F77 influenced the particle size distribution, sedimentation and flocculation characteristics of the pMDI suspension formulation. The addition of Pluronic F77 decreased the viscosity of the pMDI formulation. Formulating the suspension pMDI system with co-ground TAA and Pluronic F77 decreased the mass median aerodynamic diameter (MMAD) of the emitted aerosol and increased the percent respirable fraction (%RF). The co-ground TAA and Pluronic F77 pMDI suspension formulation exhibited greater physical stability which was due to the influence of the co-grinding technique on the physicochemical properties of the TAA particle surface and the propellant dispersion medium. The changes induced by co-grinding with Pluronic F77 improved the performance characteristics of a pMDI suspension formulation by stabilizing the suspension and influencing the flocculation characteristics. Co-grinding is a process which may be useful when developing new pMDI systems containing HFA propellants.
Administration, Inhalation↗
The midline dose distribution for a three-field radiotherapy technique.
At the University of Florida, head and neck cancer often is irradiated using parallel opposed lateral fields (with inferior borders slanted superiorly) and an anterior low neck field. A common criticism is that overlap may occur at the match-line junction of the three fields, resulting in an increased risk of radiation myelitis. One setup for treatment of the oropharynx and two for the larynx were irradiated in an anthropomorphic head and neck phantom made of tissue-equivalent polyacrylamide gel with a two-dimensional thermoluminescent dosimeter array in its sagittal midplane. The results showed that no excess radiation dose was measured at the junction of the three fields. The "spinal cord dose," as percentage of dose to the central axis of the primary field, was as follows: oropharynx setup, 15% to 100%; larynx setup with midline tracheal block, 10% to 90%; larynx setup without tracheal block, 10% to 90%. In conclusion, the University of Florida three-field technique for head and neck cancer produces no measured increase in dose at field junctions.
Acrylic Resins↗
Study of solubility of steroids in hydrofluoroalkane propellants.
The solubility of prednisone, hydrocortisone 21-acetate, hydrocortisone, dexamethasone, betamethasone 17-valerate, and danazol in hydrofluoroalkane (HFA) 134a and HFA 227 was determined at 5 degrees C and 25 degrees C. It was found that the solubility of steroid in HFA propellants was related to the melting point and the lipophilicity of the steroid. The solubility of the steroids in the binary system of HFA propellants and ethanol also was investigated in the study. Ethanol significantly increased the solubility of the steroids in HFA propellant. The magnitude of increase was related to the solubility of the corresponding steroid in ethanol alone.
Analysis of Variance↗
Influence of micronization method on the performance of a suspension triamcinolone acetonide pressurized metered-dose inhaler formulation.
The purpose of this study was to investigate the influence of micronization technique on performance and stability of the model drug formulated in a suspension-based pressurized metered-dose inhaler (pMDI). The model drug, triamcinolone acetonide (TAA), was subjected to ball milling or air-jet milling prior to formulation of the pMDI. The dose delivery characteristics of the emitted aerosol cloud were monitored for the ball-milled, air-jet-milled, and unmicronized TAA pMDI formulations prior to and after storage at 25 and 40 degrees C. Cascade impaction was used to determine the aerodynamic particle size distribution of the emitted dose. Both micronization techniques reduced the drug particle size distribution and the polydispersity of the drug particles to a similar extent, but the ball-milling technique reduced the crystallinity of the drug to a greater degree compared to the air-jet-milling technique. The air-jet-milled and unmicronized TAA pMDI displayed similar aerodynamic particle size distributions of the emitted aerosol and respirable fractions over the storage period. The ball-milled TAA resulted in a pMDI formulation with the smallest aerodynamically sized particles and the highest respirable fraction compared to the air-jet-milled or unmicronized TAA pMDI formulations. The micronization techniques significantly influenced the dose delivery characteristics as a result of different initial particle size distributions, amorphous contents, and surface energies.
Administration, Topical↗
Therapeutic actions of cyclosporine and anti-tumor necrosis factor alpha in collagen-induced arthritis and the effect of combination therapy.
OBJECTIVE: To define the mechanisms of action of 2 novel drugs, cyclosporine and anti-tumor necrosis factor alpha (TNFalpha), in collagen-induced arthritis and to determine the effect of combination therapy. METHODS: Type II collagen-immunized DBA/1 mice with established arthritis were treated with cyclosporine alone, anti-TNFalpha alone, cyclosporine plus anti-TNFalpha, or saline. RESULTS: Cyclosporine was found to ameliorate arthritis, suppress interferon-gamma (IFNgamma) production by CD4+ T cells, and reduce TNFalpha expression in arthritic joints. However, cyclosporine did not directly inhibit TNFalpha production by macrophages, indicating that the decrease in TNFalpha expression observed in vivo was probably an indirect consequence of the reduction in type 1 T helper cell activity. Anti-TNFalpha also reduced IFNgamma production by T cells, indicating that TNFalpha is involved in the cellular immune response to collagen. Combined treatment with cyclosporine plus anti-TNFalpha had an additive therapeutic effect. CONCLUSION: Although cyclosporine and anti-TNFalpha target different points in the inflammatory pathway, there is an overlap in the consequences of their actions in vivo.
Animals↗
Combination therapy in mice: what can we learn that may be useful for understanding rheumatoid arthritis?
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Animals↗
Characterization of an inclusion complex of cholesterol and hydroxypropyl-beta-cyclodextrin.
Interactions between endogenous cholesterol and cyclodextrins have been investigated by several researchers, and they found altered skin penetration of some drugs, membrane disruption, and extraction of cholesterol from the large lipoprotein particles or animal fat. In the present study, an inclusion complex composed of cholesterol and hydroxypropyl-beta-cyclodextrin (HPbetaCD) prepared by lyophilization was investigated and characterized in order to confirm these interactions. Five grams of cholesterol were dispersed in 50 ml of 73.2 mM HPbetaCD aqueous solution, mixed for 2 days, and the filtrate lyophilized. A phase solubility study was performed by mixing an excess amount of cholesterol with an aqueous solution containing increasing amounts of HPbetaCD. The amount of cholesterol in solution after mixing for 2 days at 25 degrees C was determined by HPLC. The inclusion complex was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry, and differential scanning calorimetry (DSC). An Ap-type Higuchi phase solubility diagram, DSC, FTIR, and X-ray diffraction demonstrated the formation of an inclusion complex. DSC thermograms indicated that the endothermic peaks of cholesterol and physical mixture of cholesterol with HPbetaCD due to the fusion of drug crystals, were absent in DSC thermograms obtained on the freeze dried inclusion complex. FTIR spectra indicated that some of the absorption peaks in the lyophilized inclusion complex were different from that of the physical mixture of cholesterol and HPbetaCD. X-ray diffraction patterns showed that the pure cholesterol and a physical mixture of cholesterol and HPbetaCD exhibited crystalline characteristics whereas the lyophilized inclusion complex and HPbetaCD displayed amorphous characteristics. The results indicated that the formation of a cholesterol/HPbetaCD inclusion complex is more water soluble than cholesterol alone.
2-Hydroxypropyl-beta-cyclodextrin↗
Rodent models of arthritis: relevance for human disease.
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Adjuvants, Immunologic↗
Influence of propellant composition on drug delivery from a pressurized metered-dose inhaler.
Hydrofluoroalkanes (HFAs) are used to replace chlorofluorocarbons (CFCs) as non-ozone-depleting propellants for pressurized metered-dose inhalers (pMDIs). HFA 134a and HFA 227 are used in combination to precisely manipulate the density and vapor pressure of pMDI formulations. The influence of propellant composition on the dose delivery characteristics of a suspension-based pMDI formulation was investigated. The results showed that as the density of the propellant blends approached the density of the suspended drug particles, the formulation became more physically stable and exhibited the most consistent dose delivery and greatest respirable fraction. The mass median aerodynamic diameter of the aerosolized particles contained in the emitted dose also was decreased by using propellant blends with higher vapor pressures. The performance of a suspension-based pMDI formulation was optimized by varying the propellant composition using HFA 134a and HFA 227.
Administration, Inhalation↗
Preformulation studies on Freund's incomplete adjuvant emulsion.
Freund's Incomplete Adjuvant (FIA), which is used in vaccine therapy, is a water-in-oil emulsion delivery system consisting of an aqueous internal phase containing an antigenic protein dispersed in an external phase containing a mixture of mannide monooleate and light mineral oil. Preformulation studies are reported in this investigation for FIA emulsion. The preformulation studies included the determination of the critical micelle concentration (CMC) of the formulations investigated, the surface activity of mannide monooleate at the interface between the oil phase and the aqueous phase containing ovalbumin as the model antigenic protein, and the effect of ovalbumin on the surface activity at the interface. The influence of the concentration of mannide monooleate and/or ovalbumin on the interfacial tension between light mineral oil and either purified water or 0.9% w/v normal saline solution was measured by the DuNouy Ring Method at 25 degrees C. The CMC was determined experimentally from the relationship between the concentration of the surface active agent in each formulation and the interfacial tension. The number of moles of the surface active agent per unit area at the interface (surface excess concentration) was calculated from the Gibbs' Adsorption equation. The results indicated that mannide monooleate was an effective surface active agent since the formulation containing only mannide monooleate provided the lowest magnitude of CMC. The presence of the surface active agent, mannide monooleate and/or ovalbumin, in the formulations studied reduced the interfacial tension between the two phases. The surface activity was influenced by the presence of an electrolyte (sodium chloride), a protein (ovalbumin), or mannide monooleate in the formulation. The presence of antigenic proteins in the aqueous phase of a waterin-oil emulsion influenced the effectiveness of a surface active agent in the formulation.
Chemistry, Pharmaceutical↗
Influence of temperature on the emitted dose of an oral metered dose inhaler.
The performance of metered dose inhalers is critical for the efficient delivery of drugs to the intended site of deposition in the respiratory tract. The temperature at which metered dose inhaler products are used by patients may influence the physicochemical characteristics of the emitted dose. Product performance characteristics of a metered dose inhaler containing beclomethasone dipropionate and oleic acid in a blend of chlorofluorocarbon propellants, Freon-11 and Freon-12, were determined by cascade impaction analysis and dose delivery through the valve after the metering chamber was loaded and actuated at 4 degrees C, 23 degrees C, and 40 degrees C. The dose delivered from the valve was not affected by the temperature at which the metering chamber was loaded and actuated. The mass median aerodynamic particle size of the emitted aerosol decreased and the percentage respirable fraction increased as the temperature was increased. The geometric standard deviation of the particle size distribution was not significantly affected by the temperature at which the metering chamber was loaded and actuated. The temperature at which a metered dose inhaler is used by a patient may influence the amount of drug that is potentially respirable; therefore, the dose expected to be delivered and the corresponding therapeutic effect may also be affected.
Administration, Inhalation↗
Suppression of TNF-alpha expression, inhibition of Th1 activity, and amelioration of collagen-induced arthritis by rolipram.
Rolipram is a type IV phosphodiesterase inhibitor that suppresses inflammation and TNF-alpha production. As anti-TNF-alpha therapy is effective in rheumatoid arthritis, we investigated the effect of rolipram on collagen-induced arthritis (CIA), a murine model of rheumatoid arthritis. Rolipram was administered after the onset of clinical arthritis at doses of 0.5, 3, 5, or 10 mg/kg twice daily, with a dose-dependent therapeutic effect on clinical severity and joint erosion. Immunohistochemical analysis of joints of rolipram-treated mice revealed 67% reduction in TNF-alpha-expressing cells compared with control arthritic mice. In vitro studies using bone marrow-derived macrophages confirmed that rolipram directly suppressed TNF-alpha and IL-12 production following stimulation with IFN-gamma and LPS. The effect of rolipram on T cell activity was studied by measuring Th1/Th2 cytokine production by collagen-stimulated draining lymph node cells from arthritic mice treated in vivo with rolipram. Rolipram reduced IFN-gamma production and increased IL-10, indicating that rolipram down-regulated the ongoing Th1 response to type II collagen. Finally, the effect on CIA of combination therapy was studied using rolipram plus either anti-TNF-alpha or anti-CD4 mAbs. Rolipram plus anti-TNF-alpha was not therapeutically additive, whereas rolipram plus anti-CD4 mAb was clearly additive. This result indicates that the therapeutic effects of rolipram overlap with TNF-alpha blockade, but are complementary to anti-CD4 treatment. It is therefore proposed that a major mechanism of action of rolipram in CIA is suppression of TNF-alpha activity. These findings suggest that type IV phosphodiesterase inhibitors may be effective in pathologic conditions, such as RA, with overexpression of TNF-alpha.
Animals↗