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1.
Drug Dev Ind Pharm ; : 1-12, 2024 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-39286917

RESUMO

OBJECTIVES: Bacterial infections are a noteworthy global health concern that necessitates the development of new strategies to enhance the potency and efficacy of antibiotics. Rifaximin (RFX), a broad-spectrum antibiotic, exhibits promising antibacterial activity against several bacterial strains. However, its insolubility and impermeability impede the exploitation of its full potential. The objective of the current study is to overcome the inherent caveats of RFX to exploit its maximum potential. SIGNIFICANCE: The exploitation of the full potential of antibiotics is necessary for reduction in their dosage and to minimize antibiotic pollution. This is a preliminary study aiming for maximum utilization of RFX at the target site and reduction in its release in unmetabolized form. METHODS: Gelatin is a biopolymer that has gained significant attention for biomedical applications owing to its inherent biocompatibility and biodegradability. In this study, bovine gelatin nanoparticles (BGNPs) were fabricated by the self-assembly method for their application as a carrier of RFX to enhance its antibacterial activity. The study employs a comprehensive range of experimental techniques to characterize the fabricated BGNPs such as DLS, Zeta Potential, FT-IR, AFM, SEM-EDX, and UV-Vis spectrophotometry. RESULTS: The average size of the fabricated BGNPs was 100 nm with a zeta potential value of -15.3 mV. The loading of RFX on BGNPs rendered an increase in its size to 136 nm with a zeta potential value of -16 mV. In-vitro assays and microscopic analyses were conducted to compare the antibacterial efficacy of RFX and RFX@BGNPs. An excellent loading capacity followed by sustained release of RFX from RFX@BGNPs rendered a significant enhancement in its pharmaceutical efficacy. The release of RFX from RFX@BGNPs followed the Higuchi and Korsmeyer-Peppas models. The antibacterial efficacy of RFX against Staphylococcus aureus has doubled by delivery through RFX@BGNPs, assessed by inhibitory and biofilm inhibitory assays. The enhancement in the antibacterial efficiency was further endorsed by SEM and microscopic imaging of the control and treated bacterial colonies. CONCLUSION: The study demonstrates an enhancement in the antimicrobial efficacy of RFX by its delivery in the form of RFX@BGNPs to exploit its full potential for practical applications.

2.
Pharmaceutics ; 16(7)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-39065594

RESUMO

Invasive pulmonary aspergillosis (IPA) is a fatal fungal infection with a high mortality rate. Voriconazole (VCZ) is considered a first-line therapy for IPA and shows efficacy in patients for whom other antifungal treatments have been unsuccessful. The objective of this study was to develop a high-potency VCZ-loaded liposomal system in the form of a dry-powder inhaler (DPI) using the spray-drying technique to convert liposomes into a nanocomposite microparticle (NCMP) DPI, formulated using a thin-film hydration technique. The physicochemical properties, including size, morphology, entrapment efficiency, and loading efficiency, of the formulated liposomes were evaluated. The NCMPs were then examined to determine their drug content, production yield, and aerodynamic size. The L3NCMP was formulated using a 1:1 lipid/L-leucine ratio and was selected for in vitro studies of cell viability, antifungal activity, and stability. These formulated inhalable particles offer a promising approach to the effective management of IPA.

3.
Drug Dev Ind Pharm ; 50(4): 376-386, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38533688

RESUMO

OBJECTIVE: The study evaluated physicochemical properties of eight different polymeric nanoparticles (NPs) and their interaction with lung barrier and their suitability for pulmonary drug delivery. METHODS: Eight physiochemically different NPs were fabricated from Poly lactic-co-glycolic acid (PLGA, PL) and Poly glycerol adipate-co-ω-pentadecalactone (PGA-co-PDL, PG) via emulsification-solvent evaporation. Pulmonary barrier integrity was investigated in vitro using Calu-3 under air-liquid interface. NPs internalization was investigated using a group of pharmacological inhibitors with subsequent microscopic visual confirmation. RESULTS: Eight NPs were successfully formulated from two polymers using emulsion-solvent evaporation; 200, 500 and 800 nm, negatively-charged and positively-charged. All different NPs did not alter tight junctions and PG NPs showed similar behavior to PL NPs, indicating its suitability for pulmonary drug delivery. Active endocytosis uptake mechanisms with physicochemical dependent manner were observed. In addition, NPs internalization and co-localization with lysosomes were visually confirmed indicating their vesicular transport. CONCLUSION: PG and PL NPs had shown no or low harmful effects on the barrier integrity, and with effective internalization and vesicular transport, thus, prospectively can be designed for pulmonary delivery applications.


Assuntos
Nanopartículas , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ácido Poliglicólico/química , Ácido Láctico/química , Pulmão , Linhagem Celular , Nanopartículas/química , Solventes , Portadores de Fármacos/química
4.
Colloids Surf B Biointerfaces ; 229: 113466, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37515959

RESUMO

Lung cancer is one of the most aggressive and deadliest health threats. There has been an increasing interest in non-coding RNA (ncRNA) recently, especially in the areas of carcinogenesis and tumour progression. However, ncRNA-directed therapies are still encountering obstacles on their way to the clinic. In the present article, we provide an overview on the potential of targeting ncRNA in the treatment of lung cancer. Then, we discuss the delivery challenges and recent approaches enabling the delivery of ncRNA-directed therapies to the lung cancer cells, where we illuminate some advanced technologies including chemically-modified oligonucleotides, nuclear targeting, and three-dimensional in vitro models. Furthermore, advanced non-viral delivery systems recruiting nanoparticles, biomimetic delivery systems, and extracellular vesicles are also highlighted. Lastly, the challenges limiting the clinical trials on the therapeutic targeting of ncRNAs in lung cancer and future directions to tackle them are explored.


Assuntos
Neoplasias Pulmonares , RNA não Traduzido , Humanos , RNA não Traduzido/genética , RNA não Traduzido/uso terapêutico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamento farmacológico , Carcinogênese , Terapia de Alvo Molecular/métodos
5.
Data Brief ; 49: 109363, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37456109

RESUMO

This data article collects and validates a multivariate dataset on personality traits, social, and cognitive predictors of the entrepreneurial intention of 276 students of three Omani universities. Administering a validated questionnaire, a pilot study was conducted by taking a sample of 60 responses to ensure the robustness of the survey scales. Following the pilot study, the final data were collected from 276 UG and PG level students in February 2021, which were first cleaned for missing, unengaged, and outlier responses before going ahead with statistical analyses. The data were also checked for common method bias by applying Cook's distance method which was followed by establishing the measurement model (ensuring model fitness, convergent and divergent validities) by running a CFA model in AMOS. The dataset from this data article would be of significant use for the researchers studying nascent and student entrepreneurship and Oman universities and the government in developing an entrepreneurship course curriculum.

6.
Nat Commun ; 14(1): 3377, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291107

RESUMO

The benefits of large-scale genetic studies for healthcare of the populations studied are well documented, but these genetic studies have traditionally ignored people from some parts of the world, such as South Asia. Here we describe whole genome sequence (WGS) data from 4806 individuals recruited from the healthcare delivery systems of Pakistan, India and Bangladesh, combined with WGS from 927 individuals from isolated South Asian populations. We characterize population structure in South Asia and describe a genotyping array (SARGAM) and imputation reference panel that are optimized for South Asian genomes. We find evidence for high rates of reproductive isolation, endogamy and consanguinity that vary across the subcontinent and that lead to levels of rare homozygotes that reach 100 times that seen in outbred populations. Founder effects increase the power to associate functional variants with disease processes and make South Asia a uniquely powerful place for population-scale genetic studies.


Assuntos
Povo Asiático , Efeito Fundador , Humanos , Povo Asiático/genética , Bangladesh , Homozigoto , Índia , Paquistão , População do Sul da Ásia
9.
Pharmaceutics ; 14(6)2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35745810

RESUMO

Pneumococcal disease remains a global burden, with current conjugated vaccines offering protection against the common serotype strains. However, there are over 100 serotype strains, and serotype replacement is now being observed, which reduces the effectiveness of the current vaccines. Pneumococcal surface protein A (PspA) has been investigated as a candidate for new serotype-independent pneumococcal vaccines, but requires adjuvants and/or delivery systems to improve protection. Polymeric nanoparticles (NPs) are biocompatible and, besides the antigen, can incorporate mucoadhesive and adjuvant substances such as chitosans, which improve antigen presentation at mucosal surfaces. This work aimed to define the optimal NP formulation to deliver PspA into the lungs and protect mice against lethal challenge. We prepared poly(glycerol-adipate-co-ω-pentadecalactone) (PGA-co-PDL) and poly(lactic-co-glycolic acid) (PLGA) NPs using an emulsion/solvent evaporation method, incorporating chitosan hydrochloride (HCl-CS) or carboxymethyl chitosan (CM-CS) as hybrid NPs with encapsulated or adsorbed PspA. We investigated the physicochemical properties of NPs, together with the PspA integrity and biological activity. Furthermore, their ability to activate dendritic cells in vitro was evaluated, followed by mucosal immunization targeting mouse lungs. PGA-co-PDL/HCl-CS (291 nm) or CM-CS (281 nm) NPs produced smaller sizes compared to PLGA/HCl-CS (310 nm) or CM-CS (299 nm) NPs. Moreover, NPs formulated with HCl-CS possessed a positive charge (PGA-co-PDL +17 mV, PLGA + 13 mV) compared to those formulated with CM-CS (PGA-co-PDL -20 mV, PLGA -40 mV). PspA released from NPs formulated with HCl-CS preserved the integrity and biological activity, but CM-CS affected PspA binding to lactoferrin and antibody recognition. PspA adsorbed in PGA-co-PDL/HCl-CS NPs stimulated CD80+ and CD86+ cells, but this was lower compared to when PspA was encapsulated in PLGA/HCl-CS NPs, which also stimulated CD40+ and MHC II (I-A/I-E)+ cells. Despite no differences in IgG being observed between immunized animals, PGA-co-PDL/HCl-CS/adsorbed-PspA protected 83% of mice after lethal pneumococcal challenge, while 100% of mice immunized with PLGA/HCl-CS/encapsulated-PspA were protected. Therefore, this formulation is a promising vaccine strategy, which has beneficial properties for mucosal immunization and could potentially provide serotype-independent protection.

10.
J Pak Med Assoc ; 72(5): 886-890, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35713050

RESUMO

OBJECTIVE: To assess health-related quality of life in haemodialysis patients, and the impact of various factors in this regard. METHODS: The retrospective observational cross-sectional study was conducted at The Kidney Centre Post-Graduate Training Institute, Karachi, and comprised data from June to December 2019 of patients on maintenance haemodialysis. The health-related quality of life was assessed using the self-administered Urdu version of the Kidney Disease Quality of Life-Short Form version 1.3. Data was analysed using SPSS 21. RESULTS: Of the 150 questionnaires distributed, 110(73.3%) were received fully completed. There were 64(58.2%) males, 46(41.8%) were females, 90(81.8%) were under <60 years age, 76(69%) were married, 54(49.1%) had income up to PKR50,000, 64(58.2%) had received education up to secondary school, and 56(50.9%) had been on haemodialysis for <5 years. The overall health-related quality of life mean score was 52.0±11.7, and it had no significant association with age, gender, haemodialysis duration, marital status, education level, and income of the subjects (p>0.05). CONCLUSIONS: The health-related quality of life in haemodialysis patients was not found to have significant association with age, gender, haemodialysis duration, marital status, education level, and income.


Assuntos
Nefropatias , Falência Renal Crônica , Estudos Transversais , Feminino , Humanos , Nefropatias/complicações , Falência Renal Crônica/complicações , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Masculino , Estado Civil , Pessoa de Meia-Idade , Paquistão/epidemiologia , Qualidade de Vida , Diálise Renal , Estudos Retrospectivos , Inquéritos e Questionários
12.
PLoS Genet ; 18(4): e1010093, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35381001

RESUMO

Novel drug targets for sustained reduction in body mass index (BMI) are needed to curb the epidemic of obesity, which affects 650 million individuals worldwide and is a causal driver of cardiovascular and metabolic disease and mortality. Previous studies reported that the Arg95Ter nonsense variant of GPR151, an orphan G protein-coupled receptor, is associated with reduced BMI and reduced risk of Type 2 Diabetes (T2D). Here, we further investigate GPR151 with the Pakistan Genome Resource (PGR), which is one of the largest exome biobanks of human homozygous loss-of-function carriers (knockouts) in the world. Among PGR participants, we identify eleven GPR151 putative loss-of-function (plof) variants, three of which are present at homozygosity (Arg95Ter, Tyr99Ter, and Phe175LeufsTer7), with a cumulative allele frequency of 2.2%. We confirm these alleles in vitro as loss-of-function. We test if GPR151 plof is associated with BMI, T2D, or other metabolic traits and find that GPR151 deficiency in complete human knockouts is not associated with clinically significant differences in these traits. Relative to Gpr151+/+ mice, Gpr151-/- animals exhibit no difference in body weight on normal chow and higher body weight on a high-fat diet. Together, our findings indicate that GPR151 antagonism is not a compelling therapeutic approach to treatment of obesity.


Assuntos
Diabetes Mellitus Tipo 2 , Receptores Acoplados a Proteínas G/metabolismo , Animais , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Exoma , Frequência do Gene , Humanos , Camundongos , Obesidade/genética
13.
Pharmaceutics ; 14(3)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35336035

RESUMO

The treatment of breast cancer requires long chemotherapy management, which is accompanied by severe side effects. Localized delivery of anticancer drugs helps to increase the drug concentration at the site of action and overcome such a problem. In the present study, chitosan hydrogel was prepared for local delivery of 5-Fluorouracil. The in vitro release behavior was investigated and the anticancer activity was evaluated against MCF-7 cells using MTT assay. The in vivo studies were investigated via intra-tumoral injection of a 5-FU loaded hydrogel into breast cancer of female rats. The results indicated that the modified hydrogel has excellent physicochemical properties with a sustained in vitro release profile matching a zero-order kinetic for one month. In addition, the hydrogel showed superior inhibition of cell viability compared with the untreated control group. Moreover, the in vivo studies resulted in antitumor activity with minor side effects. The tumor volume and level of tumor markers in blood were inhibited significantly by applying the hydrogel compared with the untreated control group. In conclusion, the designed injectable hydrogels are potential drug delivery systems for the treatment of breast cancer with a controlled drug release profile, which could be suitable for decreasing the side effects of chemotherapy agents.

14.
Pharmacy (Basel) ; 10(1)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35202067

RESUMO

The emerging landscape of nanomedicine includes a wide variety of active pharmaceutical ingredients and drug formulations. Their design provides nanomedicines with unique features leading to improved pharmacokinetics and pharmacodynamics. They are manufactured using conventional or biotechnological manufacturing processes. Their physical characteristics are vastly different from traditional small-molecule drugs. Pharmacists are important members of the multi-disciplinary team of scientists involved in their development and clinical application. Consequently, their training should lead to an understanding of the complexities associated with the production and evaluation of nanomedicines. Therefore, student pharmacists, post-doctoral researchers, and trainees should be given more exposure to this rapidly evolving class of therapeutics. This commentary will provide an overview of nanomedicine education within the selection of pharmacy programs globally, discuss the current regulatory challenges, and describe different approaches to incorporate nanomedicine science in pharmacy programs around the world.

15.
Life Sci ; 295: 120403, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35176277

RESUMO

Cetuximab (CTX) is known to have cytotoxic effects on several human cancer cells in vitro; however, as CTX is poorly water soluble, there is a need for improved formulations can reach cancer cells at high concentrations with low side effects. We developed (PEG-4000) polymeric nanoparticles (PEGNPs) loaded with CTX and evaluated their in vitro cytotoxicity and anticancer properties against human lung (A549) and breast (MCF-7) cancer cells. CTX-PEGNPs were formulated using the solvent evaporation technique, and their morphological properties were evaluated. Further, the effects of CTX-PEGNPs on cell viability using the MTT assay and perform gene expression analysis, DNA fragmentation measurements, and the comet assay. CTX-PEGNP showed uniformly dispersed NPs of nano-size range (253.7 ± 0.3 nm), and low polydispersity index (0.16) indicating the stability and uniformity of NPs. Further, the zeta potential of the preparations was -17.0 ± 1.8 mv. DSC and FTIR confirmed the entrapping of CTX in NPs. The results showed IC50 values of 2.26 µg/mL and 1.83 µg/mL for free CTX and CTX-PEGNPs on the A549 cancer cell line, respectively. Moreover, CTX-PEGNPs had a lower IC50 of 1.12 µg/mL in MCF-7 cells than that of free CTX (2.28 µg/mL). The expression levels of p21 and stathmin-1 were significantly decreased in both cell lines treated with CTX-PEGNPs compared to CTX alone. The CTX-PEGNP-treated cells also showed increased DNA fragmentation rates in both cancer cell lines compared with CTX alone. The results indicated that CTX-PEGNP was an improved formulation than CTX alone to induce apoptosis and DNA damage and inhibit cell proliferation through the downregulation of P21 and stathmin-1 expression.


Assuntos
Cetuximab/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Polietilenoglicóis/farmacologia , Células A549 , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cetuximab/administração & dosagem , Inibidor de Quinase Dependente de Ciclina p21/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Portadores de Fármacos/farmacologia , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , Nanopartículas/química , Polímeros , Estatmina/efeitos dos fármacos , Estatmina/metabolismo
16.
BMC Med ; 19(1): 232, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34503513

RESUMO

BACKGROUND: Genetic, lifestyle, and environmental factors can lead to perturbations in circulating lipid levels and increase the risk of cardiovascular and metabolic diseases. However, how changes in individual lipid species contribute to disease risk is often unclear. Moreover, little is known about the role of lipids on cardiovascular disease in Pakistan, a population historically underrepresented in cardiovascular studies. METHODS: We characterised the genetic architecture of the human blood lipidome in 5662 hospital controls from the Pakistan Risk of Myocardial Infarction Study (PROMIS) and 13,814 healthy British blood donors from the INTERVAL study. We applied a candidate causal gene prioritisation tool to link the genetic variants associated with each lipid to the most likely causal genes, and Gaussian Graphical Modelling network analysis to identify and illustrate relationships between lipids and genetic loci. RESULTS: We identified 253 genetic associations with 181 lipids measured using direct infusion high-resolution mass spectrometry in PROMIS, and 502 genetic associations with 244 lipids in INTERVAL. Our analyses revealed new biological insights at genetic loci associated with cardiometabolic diseases, including novel lipid associations at the LPL, MBOAT7, LIPC, APOE-C1-C2-C4, SGPP1, and SPTLC3 loci. CONCLUSIONS: Our findings, generated using a distinctive lipidomics platform in an understudied South Asian population, strengthen and expand the knowledge base of the genetic determinants of lipids and their association with cardiometabolic disease-related loci.


Assuntos
Estudo de Associação Genômica Ampla , Infarto do Miocárdio , Povo Asiático/genética , Predisposição Genética para Doença , Humanos , Lipídeos , Polimorfismo de Nucleotídeo Único , População Branca
17.
Pharmaceutics ; 13(4)2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33801614

RESUMO

The development of vaccines is one of the most significant medical accomplishments which has helped to eradicate a large number of diseases. It has undergone an evolutionary process from live attenuated pathogen vaccine to killed whole organisms or inactivated toxins (toxoids), each of them having its own advantages and disadvantages. The crucial parameters in vaccination are the generation of memory response and protection against infection, while an important aspect is the effective delivery of antigen in an intelligent manner to evoke a robust immune response. In this regard, nanotechnology is greatly contributing to developing efficient vaccine adjuvants and delivery systems. These can protect the encapsulated antigen from the host's in-vivo environment and releasing it in a sustained manner to induce a long-lasting immunostimulatory effect. In view of this, the present review article summarizes nanoscale-based adjuvants and delivery vehicles such as viral vectors, virus-like particles and virosomes; non-viral vectors namely nanoemulsions, lipid nanocarriers, biodegradable and non-degradable nanoparticles, calcium phosphate nanoparticles, colloidally stable nanoparticles, proteosomes; and pattern recognition receptors covering c-type lectin receptors and toll-like receptors.

18.
Molecules ; 26(8)2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920728

RESUMO

The aim of the present study was to assess the short-term effects of Thymoquinone (TQ) on oxidative stress, glycaemic control, and renal functions in diabetic rats. DM was induced in groups II and III with a single dose of streptozotocin (STZ), while group I received no medication (control). The rats in groups I and II were then given distilled water, while the rats in group III were given TQ at a dose of 50 mg/kg body weight/day for 4 weeks. Lipid peroxidase, nitric oxide (NO), total antioxidant capacity (TAC), glycated haemoglobin (HbA1c), lipid profiles, and renal function were assessed. Moreover, the renal tissues were used for histopathological examination. STZ increased the levels of HbA1c, lipid peroxidase, NO, and creatinine in STZ-induced diabetic rats in comparison to control rats. TAC was lower in STZ-induced diabetic rats than in the control group. Furthermore, rats treated with TQ exhibited significantly lower levels of HbA1c, lipid peroxidase, and NO than did untreated diabetic rats. TAC was higher in diabetic rats treated with TQ than in untreated diabetic rats. The histopathological results showed that treatment with TQ greatly attenuated the effect of STZ-induced diabetic nephropathy. TQ effectively adjusts glycaemic control and reduces oxidative stress in STZ-induced diabetic rats without significant damaging effects on the renal function.


Assuntos
Benzoquinonas/farmacologia , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/patologia , Modelos Animais de Doenças , Humanos , Hipoglicemia/sangue , Hipoglicemia/tratamento farmacológico , Hipoglicemia/patologia , Rim/efeitos dos fármacos , Rim/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos
19.
Int J Pharm ; 599: 120407, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33675930

RESUMO

Polymeric nanoparticles (NPs) are recognized as potential delivery vehicles for vaccines. PLGA is a biocompatible polymer synonymous with polymeric NPs, which can be coated with other polymers such as chitosan that has intrinsic adjuvant properties as well as mucoadhesive properties. Numerous modifications and variations exist for PLGA and chitosan, which can influence the NP characteristics and the resulting immunogenicity. The current study investigated variations for making chitosan coated PLGA NPs incorporating recombinant pneumococcal surface protein A from family 2, clade 4 (PspA4Pro) antigen as a vaccine targeting the vast majority of pneumococcal strains and determine the effect of the polymers on particle size, surface charge, and surface marker upregulation on a dendritic cell (DC) line in vitro. PLGA variations tested with the ester-terminal group had the greatest detriment for prospective vaccine use, due to the lowest PspA4Pro adsorption and induction of CD40 and CD86 cell surface markers on DCs. The negatively charged chitosans exhibited the lowest surface marker expressions, similar to the uncoated NP, supporting the commonly accepted notion that positive surface charge augments immunogenic effects of the NPs. However, the study indicated that NPs made from PLGA with an acid terminated group, and chitosan HCl salt, exhibit particle characteristics, antigen adsorption efficiency and immunogenicity, which could be most suitable as a vaccine formulation.


Assuntos
Quitosana , Nanopartículas , Antígenos de Superfície , Proteínas de Membrana , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Estudos Prospectivos
20.
Pharmaceuticals (Basel) ; 14(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670611

RESUMO

In this study, PGA-co-PDL nanoparticles (NPs) encapsulating model antigen, bovine serum albumin (BSA), were prepared via double emulsion solvent evaporation. In addition, chitosan hydrochloride (CHL) was incorporated into the external phase of the emulsion solvent method, which resulted in surface adsorption onto the NPs to form hybrid cationic CHL NPs. The BSA encapsulated CHL NPs were encompassed into nanocomposite microcarriers (NCMPs) composed of l-leucine to produce CHL NPs/NCMPs via spray drying. The CHL NPs/NCMPs were investigated for in vitro aerosolization, release study, cell viability and uptake, and stability of protein structure. Hybrid cationic CHL NPs (CHL: 10 mg/mL) of particle size (480.2 ± 32.2 nm), charge (+14.2 ± 0.72 mV), and BSA loading (7.28 ± 1.3 µg/mg) were produced. The adsorption pattern was determined to follow the Freundlich model. Aerosolization of CHL NPs/NCMPs indicated fine particle fraction (FPF: 46.79 ± 11.21%) and mass median aerodynamic diameter (MMAD: 1.49 ± 0.29 µm). The BSA α-helical structure was maintained, after release from the CHL NPs/NCMPs, as indicated by circular dichroism. Furthermore, dendritic cells (DCs) and A549 cells showed good viability (≥70% at 2.5 mg/mL after 4-24 h exposure, respectively). Confocal microscopy and flow cytometry data showed hybrid cationic CHL NPs were successfully taken up by DCs within 1 h of incubation. The upregulation of CD40, CD86, and MHC-II cell surface markers indicated that the DCs were successfully activated by the hybrid cationic CHL NPs. These results suggest that the CHL NPs/NCMPs technology platform could potentially be used for the delivery of proteins to the lungs for immunostimulatory applications such as vaccines.

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