Osteoblasts and bone lining cells form a near continuous layer covering the bone surface and inte... more Osteoblasts and bone lining cells form a near continuous layer covering the bone surface and interactions between these cells and the organic matrix of bone are important determinants of osteoblast proliferation and differentiation. In addition, cells of the osteoblast-lineage form functional communications with each other, with the extra-cellular matrix and with osteocytes through cytoplasmic processes extending through canaliculi in the bone. Together, these cells form a network of putative importance in the regulation of skeletal homeostasis. Cell-cell and cell-matrix interactions are mediated by members of several families of cell adhesion molecules, and knowledge of their interactions will be of fundamental importance in understanding the role of osteoblast in skeletal turnover. Here, the expression pattern of members of the major families of cell adhesion molecules by cells of the osteoblast lineage is reviewed. Special emphasis has been placed on human tissues. In addition, t...
Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the s... more Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the suppression was observed with members among HTLV-I-infected T cell lines independent of IL-2 for growth. In this study, we examined the molecular mechanism of IL-2-induced growth suppression with two HTLV-I-infected T cell lines; TL-OmI expressing endogenously three subunits, i.e. alpha, beta and gamma chains, of the IL-2 receptor, and an MT-1 transfectant expressing the endogenous alpha and gamma chains and exogenous beta chain. Our analysis revealed that IL-2 induced apoptosis in both T cell lines. Experiments with inhibitors for the proteases responsible for apoptosis signals showed that caspase 1 (IL-1 beta-converting enzyme) was not involved in apoptosis induced by IL-2. Other MT-1 sublines introduced with mutant beta chains demonstrated that IL-2-induced apoptosis required signals from both the serine-rich (S) region and acidic (A) region of the IL-2 receptor beta chain, which are essential but not critical for IL-2-mediated cell growth respectively. Collectively, IL-2 functions not only on growth promotion and prevention of apoptosis but also on induction of apoptosis, which may be implicated in physiological regulation of immune reactions by controlling growth and activation of T cells.
This work reports the in vitro characterization and evaluation of three other com m nly used mAbs... more This work reports the in vitro characterization and evaluation of three other com m nly used mAbs (J415, J533, and J591) that bind the extracellular domain of Prostate-specific membrane antigen (PSMAext). Briefly, murine mAbs J415, J533, J591, and 7E11 were radiolabeled with I and evaluated in competitive and saturation binding studies with substrates derived from LNCaP cells. J415 and J591 were conjugated to 1,4,7,10-tetraazacyclododecaneN,N′,N′′,N′′′-tetraacetic acid labeled with In. The uptake and cellular processing of these antibodies w re evaluated in viable LNCaP cells. Competition assays revealed that J415 and J591 compete for bind ing to PSMAext antigen. J533 bound to a region close to the J591 binding epitope, but J533 did not inter fer with J415 binding to PSMA. 7E11 mAb did not inhibit the binding of J415, J533, or J591 (or vice versa) whereas 7E11 binds the intracellular domain of PSMA. Saturation binding studies demonstrated that J415 and J591 bound with a similar affi...
Prostate-specific membrane antigen (PSMA) has been successfully targeted in vivo with 111In-label... more Prostate-specific membrane antigen (PSMA) has been successfully targeted in vivo with 111In-labeled 7E11 monoclonal antibody, which binds to an intracellular epitope of PSMA. This work reports the in vitro characterization and evaluation of three other commonly used mAbs (J415, J533, and J591) that bind the extracellular epitope of PSMA (PSMAext). Briefly, murine mAbs J415, J533, J591, and 7E11 were radiolabeled with 131I and evaluated in competitive and saturation binding studies with substrates derived from LNCaP cells. J415 and J591 were conjugated to 1, 4, 7, 10- tetraazacyclododecane-N, N ′ , N″ , N-tetraacetic acid labeled with 111In. The uptake and cellular processing of these antibodies were evaluated in viable LNCaP cells. Competition assays revealed that J415 and J591 compete for binding to PSMAext antigen. J533 bound to a region close to the J591 binding epitope, but J533 did not interfere with J415 binding to PSMA. 7E11 mAb did not inhibit the binding of J415, J533, or ...
Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the s... more Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the suppression was observed with members among HTLV-I-infected T cell lines independent of IL-2 for growth. In this study, we examined the molecular mechanism of IL-2-induced growth suppression with two HTLV-I-infected T cell lines; TL-OmI expressing endogenously three subunits, i.e. α, β and γ chains, of the IL-2 receptor, and an MT-1 transfectant expressing the endogenous α and γ chains and exogenous β chain. Our analysis revealed that IL-2 induced apoptosis in both T cell lines. Experiments with inhibitors for the proteases responsible for apoptosis signals showed that caspase 1 (IL-1β-converting enzyme) was not involved in apoptosis induced by IL-2. Other MT-1 sublines introduced with mutant β chains demonstrated that IL-2-induced apoptosis required signals from both the serine-rich (S) region and acidic (A) region of the IL-2 receptor β chain, which are essential but not critical for IL...
Bmi-1 gene expression increased in the hTERT siRNA group and the hTERT+Bmi-1 siRNA group compared... more Bmi-1 gene expression increased in the hTERT siRNA group and the hTERT+Bmi-1 siRNA group compared with the control siRNA group, with the highest level of gene silencing in the hTERT+Bmi-1 siRNA group. The toxicities with the complexes of Lipo, PEI, Lipo and siRNA vectors were low, but had insignificant transfection efficiencies. The gene expression levels decreased by the gene silencing of either Bmi-1 or hTERT, but when both were silenced simultaneously, the effects were synergistic.
WCDMA has emerged as the most widely adopted air interface technology for Third Generation System... more WCDMA has emerged as the most widely adopted air interface technology for Third Generation Systems as defined by the 3GPP. Evolved from CDMA and providing high spectrum efficiency, the percentage of lost call per cell represents the percentage of established calls that were lost as a result of either pilot pollution or any other reason, most importantly interference. This paper evaluates the Bit Error Rate (BER) of MIMO uplink WCDMA system in multiple interference with Maximum Mobile Transmitted Power and Equivalent Isotropic Radiated Power (EIRP) of 21dBm and 18dBm respectively. The paper further presents simulation results to support the theoretical analysis on reverse link capacity analysis in terms of cell load factor.
Infection of erythroid-lineage cells by human parvovirus B19 is characterized by a gradual cytoci... more Infection of erythroid-lineage cells by human parvovirus B19 is characterized by a gradual cytocidal effect. Accumulating evidence now implicates the nonstructural (NS1) protein of the virus in cytotoxicity, but the mechanism underlying the NS1-induced cell death is not known. Using a stringent regulatory system, we demonstrate that NS1 cytotoxicity is closely related to apoptosis, as evidenced by cell morphology, genomic DNA fragmentation, and cell cycle analysis with the human erythroleukemia cell line K562 and the erythropoietin-dependent megakaryocytic cell line UT-7/Epo. Apoptosis was significantly inhibited by an interleukin-1β (IL-1β)-converting enzyme (ICE)/CED-3 family protease inhibitor, Ac-DEVD-CHO (CPP32; caspase 3), whereas a similar inhibitor of ICE (caspase 1), Ac-YVAD-CHO, had no effect. Furthermore, stable expression of the human Bcl-2 proto-oncogene resulted in near-total protection from cell death in response to NS1 induction. Mutations engineered into the nucleos...
Deploying tools in bioinformatics and computational chemistry to standardize, analyse and store n... more Deploying tools in bioinformatics and computational chemistry to standardize, analyse and store nanobiotechnological information has gained rapid prominence after the discovery and application of DNA genomics in therapeutics. The current and traditional principles of nanobiotechnology, together with bioinformatics and analytical computational chemistry have converged into an exciting biomedical field called nanoinformatics. This review looks at this emerging sub-discipline of nanoinformatics and its intersection with nanobiotechnology in medical science in general.
The application of nanobiotechnology in molecular diagnostics is termed nanodiagnostics, and it o... more The application of nanobiotechnology in molecular diagnostics is termed nanodiagnostics, and it offers new and exciting options for personalized cancer therapy. Nanomedicine involves applications of engineered nanoparticles currently under development, or longer range research which utilizes nanoparticles for cellular repairs. The incorporation of nanobiotechnology with molecular diagnostics deploys 'nanoscale probes' for detailed analysis of cell components that exist in nanoscale dimensions. Advances in nanodiagnostic technologies are being used to facilitate the discovery of therapeutic biomarkers applicable to the effective management of cancer. In this regard, medications can then be tailored specifically to the patient based on his/ her unique genotype with minimal side effects. A nanodevice can be implanted in a patient for early diagnosis and prevention. Generally, nanodiagnostics confer several advantages, most importantly; tiny amounts of the material are required for faster and more sensitive analyses. The field of nanodiagnostics has, however, elicited certain ethical and public health concerns with regard to in vivo administration. Highlights and merits of the current nanodiagnostic technologies and their interconnection with the various nanobiotechnologies are reviewed.
International journal of pharmaceutics, Jan 6, 2006
J591 monoclonal antibody (mAb) has high affinity for prostate specific membrane antigen (PSMA) on... more J591 monoclonal antibody (mAb) has high affinity for prostate specific membrane antigen (PSMA) on prostate cancer (PCA) cells. We coupled polyethylene glycol-J591 (PEGylated J591) to a salicyl hydroxamic acid (SHA)-derivatized polyethylenimine (PEI)/DNA-betagal vector to investigate the specificity and efficiency of targeting PSMA in PCA cells through encapsulation. Coupling was facilitated via the high affinity interaction between phenyl(di)boronic acid (PDBA) and SHA molecules yielding J591/PEG/PEI/DNA-betagal polyplex. After encapsulation with poly(d,l-lactic-co-glycolic acid)-b-polyethylene glycol-b-poly(d,l-lactic-co-glycolic acid) (PLGA-PEG-PLGA) tri-block copolymer, 8-10-fold increment of gene transfection levels were attained at the optimum concentration of 0.25% (w/v) using Pluronic F68 tri-block copolymer as a control. The enhanced transfection efficiency was attributed to increased internalization and uptake of the radiolabeled plasmid in the presence of PLGA-PEG-PLGA tri...
... Furthermore, through incubation of a range of silver and gold NP formulations with SK-BR-3 ce... more ... Furthermore, through incubation of a range of silver and gold NP formulations with SK-BR-3 cells overexpressing HER2, this study ... Soman and Giorgio developed anti-VEGF labeled QDs as an early diagnostic strategy and demonstrated the possibility to measure the ...
To determine whether non-human adenovirus-specific antibodies are cross-neutralizing, rabbit and ... more To determine whether non-human adenovirus-specific antibodies are cross-neutralizing, rabbit and mouse anti-human adenovirus type 5 (HAd5), anti-bovine adenovirus type 3 (BAd3), and anti-porcine adenovirus type 3 (PAd3) sera were used in cross-virus neutralization assays. Adenovirus neutralizing antibodies were found to be virus-specific, suggesting that virus neutralizing epitope differs significantly in HAd5, BAd3, and PAd3. To further investigate whether immunity to an HAd5derived vector could be circumvented by the use of non-human adenoviruses in vivo, mice were first immunized either intranasally or intraperitoneally with HAd5, BAd3, PAd3, or BAd3 ϩ PAd3, and after development of adenovirus-specific antibodies, animals were inoculated with the HAd5 recombinant (AdCA36lacZ) containing the bacterial -galactosidase gene under the control of murine cytomegalovirus immediate-early promoter. Virus-inoculated animals developed virus-specific IgG and IgA antibodies. LacZ expression in animals initially primed with HAd5 was significantly reduced (P Ͻ 0.05), suggesting that the immune response against the vector could prevent the transgene expression following subsequent inoculation of the same vector, whereas LacZ expression in mice initially primed with BAd3, PAd3, or BAd3 ϩ PAd3 was significantly higher (P Ͼ 0.05) than that obtained in HAd5-primed animals. Our results suggest that HAd5-, BAd3-, or PAd3-based vectors may be used sequentially for human gene therapy or vaccine production as a means to avoid immunity to the vector.
To determine the potential for biodegradable alginate microspheres to be used as a delivery vehic... more To determine the potential for biodegradable alginate microspheres to be used as a delivery vehicle for DNA based vaccines, we constructed a plasmid, pMNe-gal-SV40, containing the bacterial b-galactosidase (LacZ) gene under the control of the murine cytomegalovirus (MCMV) immediate-early promoter and the simian virus 40 (SV40) polyadenylation signal. The eect of the route of administration and co-administration of adenovirus on systemic and mucosal immune responses were investigated. Mice were inoculated orally, intranasally (i.n.), intramuscularly (i.m.), subcutaneously (s.c.) or intraperitoneally (i.p.) on days 0, 14 and 28 with microspheres containing plasmid DNA, bovine adenovirus type 3 (BAd3) or plasmid DNA + BAd3. Systemic routes of immunization (i.m., s.c. and i.p.) resulted in higher LacZ-or BAd3-speci®c IgG ELISA titers compared to those obtained by mucosal routes of inoculation (oral and i.n.). Mucosal immunization led to slightly higher titers of LacZ-or BAd3-speci®c IgA at mucosal sites compared to those obtained by the various systemic routes. All the routes of immunization induced LacZ-speci®c lymphoproliferation. Co-administration of BAd3 enhanced the LacZ-speci®c IgG response irrespective of the route of administration.
We have utilized a novel polyethylenimine (PEI)/DNA-bgal vector to investigate the specificity an... more We have utilized a novel polyethylenimine (PEI)/DNA-bgal vector to investigate the specificity and efficiency of immunotargeting prostate-specific membrane antigen (PSMA). Coupling of the PSMA-specific monoclonal antibody, J591, to the vector was facilitated via the high-affinity interaction between phenyl(di)boronic acid and salicylhydroxamic acid molecules. Highly efficient gene delivery by this prostate cancer (PCA)-targeted J591/polyethylene glycol (PEG)/PEI/ DNA-bgal vector was demonstrated in PSMA-positive cells relative to controls, resulting in significant growth inhibition in vitro when the J591/PEG/PEI/DNA-p53 was used. Competition with free antibody resulted in about 90% reduction in both J591 internalization and bgal gene delivery, indicating specificity for PSMA-positive cells. More importantly, testing the efficiency of the J591/PEG/PEI/DNA-bgal targeting vector in an orthotopic PCA model in nude mice resulted in up to a 20-fold increase in gene delivery over the untargeted vector controls. The in vivo organ distribution profile also revealed bgal expression predominantly in the tumor, which was more than 1 log higher than the next highest level of expression in the lung. Furthermore, with the targeted vector containing the gene for yellow fluorescent protein or biotinylated J591, we further demonstrate in vivo that vector-mediated gene delivery is specific for both tumor cells and tumor-associated neovasculature in PSMA-positive tumors. These results suggest the potential for further optimization of this novel vector in the context of therapeutic gene delivery.
Osteoblasts and bone lining cells form a near continuous layer covering the bone surface and inte... more Osteoblasts and bone lining cells form a near continuous layer covering the bone surface and interactions between these cells and the organic matrix of bone are important determinants of osteoblast proliferation and differentiation. In addition, cells of the osteoblast-lineage form functional communications with each other, with the extra-cellular matrix and with osteocytes through cytoplasmic processes extending through canaliculi in the bone. Together, these cells form a network of putative importance in the regulation of skeletal homeostasis. Cell-cell and cell-matrix interactions are mediated by members of several families of cell adhesion molecules, and knowledge of their interactions will be of fundamental importance in understanding the role of osteoblast in skeletal turnover. Here, the expression pattern of members of the major families of cell adhesion molecules by cells of the osteoblast lineage is reviewed. Special emphasis has been placed on human tissues. In addition, t...
Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the s... more Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the suppression was observed with members among HTLV-I-infected T cell lines independent of IL-2 for growth. In this study, we examined the molecular mechanism of IL-2-induced growth suppression with two HTLV-I-infected T cell lines; TL-OmI expressing endogenously three subunits, i.e. alpha, beta and gamma chains, of the IL-2 receptor, and an MT-1 transfectant expressing the endogenous alpha and gamma chains and exogenous beta chain. Our analysis revealed that IL-2 induced apoptosis in both T cell lines. Experiments with inhibitors for the proteases responsible for apoptosis signals showed that caspase 1 (IL-1 beta-converting enzyme) was not involved in apoptosis induced by IL-2. Other MT-1 sublines introduced with mutant beta chains demonstrated that IL-2-induced apoptosis required signals from both the serine-rich (S) region and acidic (A) region of the IL-2 receptor beta chain, which are essential but not critical for IL-2-mediated cell growth respectively. Collectively, IL-2 functions not only on growth promotion and prevention of apoptosis but also on induction of apoptosis, which may be implicated in physiological regulation of immune reactions by controlling growth and activation of T cells.
This work reports the in vitro characterization and evaluation of three other com m nly used mAbs... more This work reports the in vitro characterization and evaluation of three other com m nly used mAbs (J415, J533, and J591) that bind the extracellular domain of Prostate-specific membrane antigen (PSMAext). Briefly, murine mAbs J415, J533, J591, and 7E11 were radiolabeled with I and evaluated in competitive and saturation binding studies with substrates derived from LNCaP cells. J415 and J591 were conjugated to 1,4,7,10-tetraazacyclododecaneN,N′,N′′,N′′′-tetraacetic acid labeled with In. The uptake and cellular processing of these antibodies w re evaluated in viable LNCaP cells. Competition assays revealed that J415 and J591 compete for bind ing to PSMAext antigen. J533 bound to a region close to the J591 binding epitope, but J533 did not inter fer with J415 binding to PSMA. 7E11 mAb did not inhibit the binding of J415, J533, or J591 (or vice versa) whereas 7E11 binds the intracellular domain of PSMA. Saturation binding studies demonstrated that J415 and J591 bound with a similar affi...
Prostate-specific membrane antigen (PSMA) has been successfully targeted in vivo with 111In-label... more Prostate-specific membrane antigen (PSMA) has been successfully targeted in vivo with 111In-labeled 7E11 monoclonal antibody, which binds to an intracellular epitope of PSMA. This work reports the in vitro characterization and evaluation of three other commonly used mAbs (J415, J533, and J591) that bind the extracellular epitope of PSMA (PSMAext). Briefly, murine mAbs J415, J533, J591, and 7E11 were radiolabeled with 131I and evaluated in competitive and saturation binding studies with substrates derived from LNCaP cells. J415 and J591 were conjugated to 1, 4, 7, 10- tetraazacyclododecane-N, N ′ , N″ , N-tetraacetic acid labeled with 111In. The uptake and cellular processing of these antibodies were evaluated in viable LNCaP cells. Competition assays revealed that J415 and J591 compete for binding to PSMAext antigen. J533 bound to a region close to the J591 binding epitope, but J533 did not interfere with J415 binding to PSMA. 7E11 mAb did not inhibit the binding of J415, J533, or ...
Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the s... more Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the suppression was observed with members among HTLV-I-infected T cell lines independent of IL-2 for growth. In this study, we examined the molecular mechanism of IL-2-induced growth suppression with two HTLV-I-infected T cell lines; TL-OmI expressing endogenously three subunits, i.e. α, β and γ chains, of the IL-2 receptor, and an MT-1 transfectant expressing the endogenous α and γ chains and exogenous β chain. Our analysis revealed that IL-2 induced apoptosis in both T cell lines. Experiments with inhibitors for the proteases responsible for apoptosis signals showed that caspase 1 (IL-1β-converting enzyme) was not involved in apoptosis induced by IL-2. Other MT-1 sublines introduced with mutant β chains demonstrated that IL-2-induced apoptosis required signals from both the serine-rich (S) region and acidic (A) region of the IL-2 receptor β chain, which are essential but not critical for IL...
Bmi-1 gene expression increased in the hTERT siRNA group and the hTERT+Bmi-1 siRNA group compared... more Bmi-1 gene expression increased in the hTERT siRNA group and the hTERT+Bmi-1 siRNA group compared with the control siRNA group, with the highest level of gene silencing in the hTERT+Bmi-1 siRNA group. The toxicities with the complexes of Lipo, PEI, Lipo and siRNA vectors were low, but had insignificant transfection efficiencies. The gene expression levels decreased by the gene silencing of either Bmi-1 or hTERT, but when both were silenced simultaneously, the effects were synergistic.
WCDMA has emerged as the most widely adopted air interface technology for Third Generation System... more WCDMA has emerged as the most widely adopted air interface technology for Third Generation Systems as defined by the 3GPP. Evolved from CDMA and providing high spectrum efficiency, the percentage of lost call per cell represents the percentage of established calls that were lost as a result of either pilot pollution or any other reason, most importantly interference. This paper evaluates the Bit Error Rate (BER) of MIMO uplink WCDMA system in multiple interference with Maximum Mobile Transmitted Power and Equivalent Isotropic Radiated Power (EIRP) of 21dBm and 18dBm respectively. The paper further presents simulation results to support the theoretical analysis on reverse link capacity analysis in terms of cell load factor.
Infection of erythroid-lineage cells by human parvovirus B19 is characterized by a gradual cytoci... more Infection of erythroid-lineage cells by human parvovirus B19 is characterized by a gradual cytocidal effect. Accumulating evidence now implicates the nonstructural (NS1) protein of the virus in cytotoxicity, but the mechanism underlying the NS1-induced cell death is not known. Using a stringent regulatory system, we demonstrate that NS1 cytotoxicity is closely related to apoptosis, as evidenced by cell morphology, genomic DNA fragmentation, and cell cycle analysis with the human erythroleukemia cell line K562 and the erythropoietin-dependent megakaryocytic cell line UT-7/Epo. Apoptosis was significantly inhibited by an interleukin-1β (IL-1β)-converting enzyme (ICE)/CED-3 family protease inhibitor, Ac-DEVD-CHO (CPP32; caspase 3), whereas a similar inhibitor of ICE (caspase 1), Ac-YVAD-CHO, had no effect. Furthermore, stable expression of the human Bcl-2 proto-oncogene resulted in near-total protection from cell death in response to NS1 induction. Mutations engineered into the nucleos...
Deploying tools in bioinformatics and computational chemistry to standardize, analyse and store n... more Deploying tools in bioinformatics and computational chemistry to standardize, analyse and store nanobiotechnological information has gained rapid prominence after the discovery and application of DNA genomics in therapeutics. The current and traditional principles of nanobiotechnology, together with bioinformatics and analytical computational chemistry have converged into an exciting biomedical field called nanoinformatics. This review looks at this emerging sub-discipline of nanoinformatics and its intersection with nanobiotechnology in medical science in general.
The application of nanobiotechnology in molecular diagnostics is termed nanodiagnostics, and it o... more The application of nanobiotechnology in molecular diagnostics is termed nanodiagnostics, and it offers new and exciting options for personalized cancer therapy. Nanomedicine involves applications of engineered nanoparticles currently under development, or longer range research which utilizes nanoparticles for cellular repairs. The incorporation of nanobiotechnology with molecular diagnostics deploys 'nanoscale probes' for detailed analysis of cell components that exist in nanoscale dimensions. Advances in nanodiagnostic technologies are being used to facilitate the discovery of therapeutic biomarkers applicable to the effective management of cancer. In this regard, medications can then be tailored specifically to the patient based on his/ her unique genotype with minimal side effects. A nanodevice can be implanted in a patient for early diagnosis and prevention. Generally, nanodiagnostics confer several advantages, most importantly; tiny amounts of the material are required for faster and more sensitive analyses. The field of nanodiagnostics has, however, elicited certain ethical and public health concerns with regard to in vivo administration. Highlights and merits of the current nanodiagnostic technologies and their interconnection with the various nanobiotechnologies are reviewed.
International journal of pharmaceutics, Jan 6, 2006
J591 monoclonal antibody (mAb) has high affinity for prostate specific membrane antigen (PSMA) on... more J591 monoclonal antibody (mAb) has high affinity for prostate specific membrane antigen (PSMA) on prostate cancer (PCA) cells. We coupled polyethylene glycol-J591 (PEGylated J591) to a salicyl hydroxamic acid (SHA)-derivatized polyethylenimine (PEI)/DNA-betagal vector to investigate the specificity and efficiency of targeting PSMA in PCA cells through encapsulation. Coupling was facilitated via the high affinity interaction between phenyl(di)boronic acid (PDBA) and SHA molecules yielding J591/PEG/PEI/DNA-betagal polyplex. After encapsulation with poly(d,l-lactic-co-glycolic acid)-b-polyethylene glycol-b-poly(d,l-lactic-co-glycolic acid) (PLGA-PEG-PLGA) tri-block copolymer, 8-10-fold increment of gene transfection levels were attained at the optimum concentration of 0.25% (w/v) using Pluronic F68 tri-block copolymer as a control. The enhanced transfection efficiency was attributed to increased internalization and uptake of the radiolabeled plasmid in the presence of PLGA-PEG-PLGA tri...
... Furthermore, through incubation of a range of silver and gold NP formulations with SK-BR-3 ce... more ... Furthermore, through incubation of a range of silver and gold NP formulations with SK-BR-3 cells overexpressing HER2, this study ... Soman and Giorgio developed anti-VEGF labeled QDs as an early diagnostic strategy and demonstrated the possibility to measure the ...
To determine whether non-human adenovirus-specific antibodies are cross-neutralizing, rabbit and ... more To determine whether non-human adenovirus-specific antibodies are cross-neutralizing, rabbit and mouse anti-human adenovirus type 5 (HAd5), anti-bovine adenovirus type 3 (BAd3), and anti-porcine adenovirus type 3 (PAd3) sera were used in cross-virus neutralization assays. Adenovirus neutralizing antibodies were found to be virus-specific, suggesting that virus neutralizing epitope differs significantly in HAd5, BAd3, and PAd3. To further investigate whether immunity to an HAd5derived vector could be circumvented by the use of non-human adenoviruses in vivo, mice were first immunized either intranasally or intraperitoneally with HAd5, BAd3, PAd3, or BAd3 ϩ PAd3, and after development of adenovirus-specific antibodies, animals were inoculated with the HAd5 recombinant (AdCA36lacZ) containing the bacterial -galactosidase gene under the control of murine cytomegalovirus immediate-early promoter. Virus-inoculated animals developed virus-specific IgG and IgA antibodies. LacZ expression in animals initially primed with HAd5 was significantly reduced (P Ͻ 0.05), suggesting that the immune response against the vector could prevent the transgene expression following subsequent inoculation of the same vector, whereas LacZ expression in mice initially primed with BAd3, PAd3, or BAd3 ϩ PAd3 was significantly higher (P Ͼ 0.05) than that obtained in HAd5-primed animals. Our results suggest that HAd5-, BAd3-, or PAd3-based vectors may be used sequentially for human gene therapy or vaccine production as a means to avoid immunity to the vector.
To determine the potential for biodegradable alginate microspheres to be used as a delivery vehic... more To determine the potential for biodegradable alginate microspheres to be used as a delivery vehicle for DNA based vaccines, we constructed a plasmid, pMNe-gal-SV40, containing the bacterial b-galactosidase (LacZ) gene under the control of the murine cytomegalovirus (MCMV) immediate-early promoter and the simian virus 40 (SV40) polyadenylation signal. The eect of the route of administration and co-administration of adenovirus on systemic and mucosal immune responses were investigated. Mice were inoculated orally, intranasally (i.n.), intramuscularly (i.m.), subcutaneously (s.c.) or intraperitoneally (i.p.) on days 0, 14 and 28 with microspheres containing plasmid DNA, bovine adenovirus type 3 (BAd3) or plasmid DNA + BAd3. Systemic routes of immunization (i.m., s.c. and i.p.) resulted in higher LacZ-or BAd3-speci®c IgG ELISA titers compared to those obtained by mucosal routes of inoculation (oral and i.n.). Mucosal immunization led to slightly higher titers of LacZ-or BAd3-speci®c IgA at mucosal sites compared to those obtained by the various systemic routes. All the routes of immunization induced LacZ-speci®c lymphoproliferation. Co-administration of BAd3 enhanced the LacZ-speci®c IgG response irrespective of the route of administration.
We have utilized a novel polyethylenimine (PEI)/DNA-bgal vector to investigate the specificity an... more We have utilized a novel polyethylenimine (PEI)/DNA-bgal vector to investigate the specificity and efficiency of immunotargeting prostate-specific membrane antigen (PSMA). Coupling of the PSMA-specific monoclonal antibody, J591, to the vector was facilitated via the high-affinity interaction between phenyl(di)boronic acid and salicylhydroxamic acid molecules. Highly efficient gene delivery by this prostate cancer (PCA)-targeted J591/polyethylene glycol (PEG)/PEI/ DNA-bgal vector was demonstrated in PSMA-positive cells relative to controls, resulting in significant growth inhibition in vitro when the J591/PEG/PEI/DNA-p53 was used. Competition with free antibody resulted in about 90% reduction in both J591 internalization and bgal gene delivery, indicating specificity for PSMA-positive cells. More importantly, testing the efficiency of the J591/PEG/PEI/DNA-bgal targeting vector in an orthotopic PCA model in nude mice resulted in up to a 20-fold increase in gene delivery over the untargeted vector controls. The in vivo organ distribution profile also revealed bgal expression predominantly in the tumor, which was more than 1 log higher than the next highest level of expression in the lung. Furthermore, with the targeted vector containing the gene for yellow fluorescent protein or biotinylated J591, we further demonstrate in vivo that vector-mediated gene delivery is specific for both tumor cells and tumor-associated neovasculature in PSMA-positive tumors. These results suggest the potential for further optimization of this novel vector in the context of therapeutic gene delivery.
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