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1.
Front Artif Intell ; 5: 915922, 2022.
Article in English | MEDLINE | ID: mdl-36467559

ABSTRACT

Due to the huge surge in remote work all over the world caused by the COVID-19 pandemic, today's work is largely defined by tools for information exchange as well as new complex problems that must be solved. Design Thinking offers a well-known and established methodological approach for iterative, collaborative and interdisciplinary problem solving. Still, recent circumstances shed a new light on how to facilitate Design Thinking activities in a remote rather than an analog way. Due to Design Thinking's high production of artifacts and its focus on communication and interaction between team members, the theory of Distributed Cognition, specifically the Distributed Cognition for Teamwork (DiCoT) framework, provides an interesting perspective on the recent going-remote of Design Thinking activities. For this, we first highlight differences of analog vs. remote Design Thinking by analyzing corresponding literature from the recent years. Next, we apply the DiCoT framework to those findings, pointing out implications for practical facilitation of Design Thinking activities in an analog and remote setting. Finally, we discuss opportunities through artificial intelligence-based technologies and methods.

2.
J Photochem Photobiol B ; 209: 111953, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32653859

ABSTRACT

Trachoma is a devastating neglected tropical disease caused by Chlamydia trachomatis and the leading global cause of infectious blindness. Although antibiotic treatment against trachoma is efficient (SAFE strategy), additional affordable therapeutic strategies are of high interest. Water-filtered infrared A and visible light (wIRA/VIS) irradiation has proven to reduce chlamydial infectivity in vitro and ex vivo. The aim of this study was to evaluate whether wIRA/VIS can reduce chlamydial infection load and/or ocular pathology in vivo, in a guinea pig model of inclusion conjunctivitis. Guinea pigs were infected with 1 × 106 inclusion-forming units/eye of Chlamydia caviae via the ocular conjunctiva on day 0. In infected animals, wIRA/VIS irradiation (2100 W/m2) was applied on day 2 (single treatment) and on days 2 and 4 (double treatment) post-infection (pi). wIRA/VIS reduced the clinical pathology score on days 7 and 14 pi and the conjunctival chlamydial load on days 2, 4, 7, and 14 pi in comparison with C. caviae-infected, not irradiated, controls. Furthermore, numbers of chlamydial inclusions were decreased in wIRA/VIS treated C. caviae-infected guinea pigs on day 21 pi compared to C. caviae-infected, non-irradiated, controls. Double treatment with wIRA/VIS (days 2 and 4 pi) was more efficient than a single treatment on day 2 pi. wIRA/VIS treatment did neither induce macroscopic nor histologic changes in ocular tissues. Our results indicate that wIRA/VIS shows promising efficacy to reduce chlamydial infectivity in vivo without causing irradiation related pathologies in the follow-up period. wIRA/VIS irradiation is a promising approach to reduce trachoma transmission and pathology of ocular chlamydial infection.


Subject(s)
Chlamydia/isolation & purification , Conjunctivitis, Inclusion/radiotherapy , Infrared Rays , Light , Animals , Colony Count, Microbial , Conjunctivitis, Inclusion/microbiology , Disease Models, Animal , Guinea Pigs
3.
J Appl Phycol ; 30(4): 2601-2610, 2018.
Article in English | MEDLINE | ID: mdl-30147240

ABSTRACT

Ocular chlamydial infections with the ocular serovars A, B, Ba, and C of Chlamydia trachomatis represent the world's leading cause of infectious blindness. Carrageenans are naturally occurring, sulfated polysaccharides generally considered safe for food and topical applications. Carrageenans can inhibit infection caused by a variety of viruses and bacteria. To investigate whether iota-carrageenan (I-C) isolated from the red alga Chondrus crispus could prevent ocular chlamydial infection, we assessed if targeted treatment of the conjunctival mucosa with I-C affects chlamydial attachment, entry, and replication in the host cell. Immortalized human conjunctival epithelial cells were treated with I-C prior to C. trachomatis infection and analyzed by flow cytometry and immunofluorescence microscopy. In vivo effects were evaluated in an ocular guinea pig inclusion conjunctivitis model. Ocular pathology was graded daily, and chlamydial clearance was investigated. Our study showed that I-C reduces the infectivity of C. trachomatis in vitro. In vivo results showed a slight reduced ocular pathology and significantly less shedding of infectious elementary bodies by infected animals. Our results indicate that I-C could be a promising agent to reduce the transmission of ocular chlamydial infection and opens perspectives to develop prophylactic approaches to block C. trachomatis entry into the host cell.

4.
Sci Rep ; 8(1): 7432, 2018 05 09.
Article in English | MEDLINE | ID: mdl-29743637

ABSTRACT

Trachoma, the leading infectious cause of blindness, is caused by Chlamydia trachomatis (Ct), a bacterium of the phylum Chlamydiae. Recent investigations revealed the existence of additional families within the phylum Chlamydiae, also termed Chlamydia-like organisms (CLOs). In this study, the frequency of Ct and CLOs was examined in the eyes of healthy Sudanese (control) participants and those with trachoma (case). We tested 96 children (54 cases and 42 controls) and 93 adults (51 cases and 42 controls) using broad-range Chlamydiae and Ct-specific (omcB) real-time PCR. Samples positive by broad-range Chlamydiae testing were subjected to DNA sequencing. Overall Chlamydiae prevalence was 36%. Sequences corresponded to unclassified and classified Chlamydiae. Ct infection rate was significantly higher in children (31.5%) compared to adults (0%) with trachoma (p < 0.0001). In general, 21.5% of adults and 4.2% of children tested positive for CLOs (p = 0.0003). Our findings are consistent with previous investigations describing the central role of Ct in trachoma among children. This is the first study examining human eyes for the presence of CLOs. We found an age-dependent distribution of CLO DNA in human eyes with significantly higher positivity in adults. Further studies are needed to understand the impact of CLOs in trachoma pathogenicity and/or protection.


Subject(s)
Chlamydia trachomatis/isolation & purification , Chlamydia trachomatis/physiology , Chlamydiaceae/isolation & purification , Chlamydiaceae/physiology , Endemic Diseases , Eye/microbiology , Trachoma/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , DNA, Bacterial/analysis , Female , Humans , Infant , Male , Middle Aged , Phylogeny , Trachoma/microbiology , Young Adult
5.
Cell Mol Bioeng ; 11(6): 483-494, 2018 Dec.
Article in English | MEDLINE | ID: mdl-31719895

ABSTRACT

INTRODUCTION: Directed fibroblast migration is central to highly proliferative processes in regenerative medicine and developmental biology. However, the mechanisms by which single fibroblasts affect each other's directional decisions, while chemotaxing in microscopic pores, are not well understood. METHODS: We explored effects of cell sequence and mitosis on fibroblast platelet-derived growth factor-BB (PDGF-BB)-induced migration in microfluidic mazes with two possible through paths: short and long. Additionally, image-based modeling of the chemoattractant's diffusion, consumption and decay, was used to explain the experimental observations. RESULTS: It both cases, the cells displayed behavior that is contradictory to expectation based on the global chemoattractant gradient pre-established in the maze. In case of the sequence, the cells tend to alternate when faced with a bifurcation: if a leading cell takes the shorter (steeper gradient) path, the cell following it chooses the longer (weaker gradient) path, and vice versa. Image-based modeling of the process showed that the local PDGF-BB consumption by the individual fibroblasts may be responsible for this phenomenon. Additionally, it was found that when a mother cell divides, its two daughters go in opposite directions (even if it means migrating against the chemoattractant gradient and overcoming on-going cell traffic). CONCLUSIONS: It is apparent that micro-confined fibroblasts modify each other's directional decisions in a manner that is counter-intuitive to what is expected from classical chemotaxis theory. Consequently, accounting for these effects could lead to a better understanding of tissue generation in vivo, and result in more advanced engineered tissue products in vitro.

6.
PLoS One ; 12(7): e0180551, 2017.
Article in English | MEDLINE | ID: mdl-28678871

ABSTRACT

Following infection, the balance between protective immunity and immunopathology often depends on the initial infectious load. Several studies have investigated the effect of infectious dose; however, the mechanism by which infectious dose affects disease outcomes and the development of a protective immune response is not known. The aim of this study was to investigate how the infectious dose modulates the local and systemic humoral and the cellular immune responses during primary ocular chlamydial infection in the guinea pig animal model. Guinea pigs were infected by ocular instillation of a Chlamydophila caviae-containing eye solution in the conjunctival sac in three different doses: 1×102, 1×104, and 1×106 inclusion forming units (IFUs). Ocular pathology, chlamydial clearance, local and systemic C. caviae-specific humoral and cellular immune responses were assessed. All inocula of C. caviae significantly enhanced the local production of C. caviae-specific IgA in tears, but only guinea pigs infected with the higher doses showed significant changes in C. caviae-specific IgA levels in vaginal washes and serum. On complete resolution of infection, the low dose of C. caviae did not alter the ratio of CD4+ and CD8+ cells within guinea pigs' submandibular lymph node (SMLN) lymphocytes while the higher doses increased the percentages of CD4+ and CD8+ cells within the SMLN lymphocytes. A significant negative correlation between pathology intensity and the percentage of CD4+ and CD8+ cells within SMLN lymphocyte pool at selected time points post-infection was recorded for both 1×104, and 1×106 IFU infected guinea pigs. The relevance of the observed dose-dependent differences on the immune response should be further investigated in repeated ocular chlamydial infections.


Subject(s)
Chlamydophila Infections/immunology , Chlamydophila Infections/microbiology , Chlamydophila , Immunity, Cellular , Immunity, Humoral , Animals , Chlamydophila/pathogenicity , Dose-Response Relationship, Immunologic , Eye Infections , Guinea Pigs , Virulence/immunology
7.
Article in English | MEDLINE | ID: mdl-28660176

ABSTRACT

Chlamydia trachomatis (Ct) can induce scarring disease of the ocular mucosa, known as trachoma, the most common infectious cause of blindness worldwide. We hypothesized that epithelial-mesenchymal transition (EMT) contributes to the fibrotic process in trachomatous scarring. Infection of human conjunctival epithelial cells (HCjE) with Ct activated signaling pathways involved in EMT induction, which was correlated with decreased expression of E-cadherin, guardian of the epithelial phenotype. In addition, Ct infection was associated with increased expression of two mesenchymal cell markers: fibronectin and α-SMA. The DNA methylation statuses of selected regions of E-cadherin, fibronectin, and α-SMA genes revealed that Ct infection was accompanied with changes in DNA methylation of the E-cadherin promoter, while the expression of the two mesenchymal markers was not related with this epigenetic event. Our data suggest that Ct infection of conjunctival epithelial cells induces EMT-like changes that go along with modification of the methylation profile of the E-cadherin promoter and could, as one of the earliest events, contribute to processes triggering conjunctival scarring.


Subject(s)
Actins/metabolism , Cadherins/metabolism , Chlamydia trachomatis/pathogenicity , DNA Methylation , Epithelial-Mesenchymal Transition , Fibronectins/metabolism , Promoter Regions, Genetic , Trachoma/metabolism , Actins/genetics , Animals , Cadherins/genetics , Cdh1 Proteins/genetics , Cdh1 Proteins/metabolism , Cell Line , Down-Regulation , Epithelial Cells/metabolism , Fibronectins/genetics , Gene Expression Regulation , Humans , Mice , Signal Transduction , Trachoma/microbiology
8.
Cornea ; 36(6): 712-718, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28399036

ABSTRACT

PURPOSE: To investigate toxicity associated with buffers commonly used in topical ocular drug formulations using a human corneal-limbal epithelial (HCLE) and a human conjunctival epithelial (HCjE) cell model. METHODS: HCLE and HCjE cells were incubated for 10, 30, or 60 minutes with 4 different buffers based on borate, citrate, phosphate, and Tris-HCl at 10, 50, and 100 mM concentrations. To detect possible delayed effects on cell viability, after 60 minutes of buffer incubation, cells were further incubated for 24 hours with a cell medium. Cell viability was determined using a colorimetric XTT-based assay. The morphology of cells was also investigated. RESULTS: HCjE cells showed more sensitivity to buffer incubation than HCLE cells. The 100 mM phosphate buffer displayed significant delayed effects on cell viability of HCLE 16.8 ± 4.8% and HCjE 39.2 ± 6.1% cells after 60 minutes of exposure (P < 0.05). HCjE cell viability was reduced after 60 minutes incubations with 50 and 100 mM citrate buffer to 42.8 ± 6.5% and 39.3 ± 7.9%, respectively, and even lower percentages at the delayed time point (both P < 0.05). HCLE cell morphology was distinctly altered by 100 mM phosphate and Tris buffers after 30 minutes, whereas HCjE cells already showed marked changes after 10 minutes of exposure to 100 mM citrate and phosphate buffers. CONCLUSIONS: We observed a time-dependent decrease of viability in both HCLE and HCjE cells exposed to higher buffer concentrations. Therefore, we propose further in vivo studies to translate these finding to humans to discern the real effects of the buffer concentration in eye drops on the ocular surface.


Subject(s)
Conjunctiva/cytology , Epithelial Cells/drug effects , Limbus Corneae/cytology , Ophthalmic Solutions/toxicity , Buffers , Cell Line , Cell Survival/drug effects , Humans , Ophthalmic Solutions/chemistry , Pharmaceutical Preparations/chemistry , Time Factors
9.
J Photochem Photobiol B ; 165: 340-350, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27838487

ABSTRACT

Repeated ocular infections with Chlamydia trachomatis trigger the development of trachoma, the most common cause of infectious blindness worldwide. Water-filtered infrared A (wIRA) has shown positive effects on cultured cells and human skin. Our aim was to evaluate the potential of wIRA as a possible non-chemical treatment for trachoma patients. We both modeled ocular chlamydial infections using C. trachomatis B to infect human conjunctival epithelial cells (HCjE) and studied the effects of wIRA on non-infected ocular structures with two ex vivo eye models. We focused on the temperature development during wIRA irradiation in cell culture and perfused pig eyes to exclude potentially harmful side effects. Furthermore, cell viability of HCjE and cytotoxicity in mouse retina explants was analyzed. We demonstrated a significant wIRA-dependent reduction of chlamydial infectivity in HCjE cells. Moreover, we observed that wIRA treatment of HCjE prior to infection was sufficient to inhibit chlamydial infectivity and that visible light enhances the effect of wIRA. Irradiation did not reduce cell viability and there was no indication of retinal damage post treatment. Additionally, temperatures during wIRA exposure did not markedly exceed physiological eye temperatures, suggesting that hyperthermia-related lesions are unlikely. For clinical applications, further exploration of wIRA as a non-chemical treatment device in an experimental animal model is essential.


Subject(s)
Disease Models, Animal , Infrared Rays/therapeutic use , Trachoma/prevention & control , Water , Animals , Mice , Swine
10.
PLoS One ; 11(9): e0157875, 2016.
Article in English | MEDLINE | ID: mdl-27636704

ABSTRACT

Recent advances in the development of chlamydia vaccines, using live-attenuated or ultraviolet light-inactivated chlamydia, are paving the way for new possibilities to oppose the societal challenges posed by chlamydia-related diseases, such as blinding trachoma. An effective subunit vaccine would mitigate the risks associated with the use of a whole-cell vaccine. Our rationale for the design of an efficient subunit vaccine against Chlamydia trachomatis (Ct) is based on the membrane proteins involved in the initial Ct-host cell contact and on the route of immunization that mimics the natural infection process (i.e., via the ocular mucosa). The first aim of our study was to characterize the specific conjunctival and vaginal immune responses following eye drop immunization in BALB/c mice, using the N-terminal portion of the Ct serovar E polymorphic membrane protein C (N-PmpC) as the subunit vaccine antigen. Second, we aimed to examine the adjuvant properties of the probiotic Lactobacillus rhamnosus (LB) when formulated with N-PmpC. N-PmpC applied alone stimulated the production of N-PmpC- and Ct serovar B-specific antibodies in serum, tears and vaginal washes, whereas the combination with LB significantly enhanced these responses. The N-PmpC/LB combination initiated a T cell response characterized by an elevated percentage of CD25+ T cells and CD8+ effector T cells, enhanced CD4+ T-helper 1 skewing, and increased regulatory T cell responses. Together, these results show that eye drop vaccination with combined use of N-PmpC and a live probiotic LB stimulates specific cellular and humoral immune responses, not only locally in the conjunctiva but also in the vaginal mucosa, which could be a promising approach in Ct vaccine development.


Subject(s)
Bacterial Proteins/immunology , Chlamydia trachomatis/immunology , Lacticaseibacillus rhamnosus , Mouth Mucosa/immunology , Probiotics , Animals , Female , Mice , Mice, Inbred BALB C
11.
Microbes Infect ; 18(4): 254-62, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26706818

ABSTRACT

The aim of this study was to determine whether infectious dose of Chlamydia caviae after repeated infections influences the immunological responses and subsequent clearance of pathogen at the ocular surface of guinea pigs. Animals were infected three times via the conjunctiva at six- and twelve-week intervals by applying either 1 × 10(4) or 1 × 10(6) inclusion-forming units (IFUs) of C. caviae. Ocular pathology, infection course, C. caviae-specific serum IgG levels and their capacity to bind and neutralize infection ex vivo were assessed. Animals infected with 1 × 10(4) IFUs had completely diminished ocular infection and pathology after the 2nd infection with increased levels of C. caviae-specific serum IgG and their effective capacity to bind and neutralize C. caviae. Only partial protection was observed in animals infected with 1 × 10(6) IFUs after the 2nd and 3rd infections. Our findings show that full protection was observed in animals repeatedly infected with the lower dose. The lower dose appeared not to compromise the host immune system, thereby enabling fast clearance of the pathogen and the establishment of competent neutralizing antibodies.


Subject(s)
Chlamydia Infections/immunology , Chlamydia Infections/microbiology , Chlamydia/immunology , Chlamydia/pathogenicity , Eye Infections/immunology , Eye Infections/microbiology , Animals , Antibodies, Bacterial/blood , Antibodies, Neutralizing/blood , Chlamydia Infections/pathology , Chlamydia Infections/prevention & control , Disease Models, Animal , Eye Infections/pathology , Eye Infections/prevention & control , Guinea Pigs , Immunoglobulin G/blood
12.
EuPA Open Proteom ; 10: 63-69, 2016 Mar.
Article in English | MEDLINE | ID: mdl-29900103

ABSTRACT

Chlamydia trachomatis (Ct) is a human pathogen causing trachoma and infertility. We investigated acetylation at lysine residues of chlamydial antigenic proteins: major outer membrane protein (MOMP), 60 kDa chaperonin (chlamydial Hsp60), elongation factor G (EF-G), enolase and the polymorphic membrane proteins PmpB, PmpE and PmpF. 60 kDa chaperonin, EF-G and PmpB showed the highest degree of acetylation. Our data show that important Ct antigens could be post-translationally modified by acetylation of lysine residues at multiple sites. Further studies are needed to investigate total acetylome of Ct and the impact PTMs might have on Ct biology and pathogenicity.

13.
PLoS One ; 10(12): e0144380, 2015.
Article in English | MEDLINE | ID: mdl-26656797

ABSTRACT

Trachoma, caused by the intracellular bacterium Chlamydia trachomatis (Ct), remains the world's leading preventable infectious cause of blindness. Recent attempts to develop effective vaccines rely on modified chlamydial antigen delivery platforms. As the mechanisms engaged in the pathology of the disease are not fully understood, designing a subunit vaccine specific to chlamydial antigens could improve safety for human use. We propose the delivery of chlamydia-specific antigens to the ocular mucosa using particulate carriers, bacterial ghosts (BGs). We therefore characterized humoral and cellular immune responses after conjunctival and subcutaneous immunization with a N-terminal portion (amino acid 1-893) of the chlamydial polymorphic membrane protein C (PmpC) of Ct serovar B, expressed in probiotic Escherichia coli Nissle 1917 bacterial ghosts (EcN BGs) in BALB/c mice. Three immunizations were performed at two-week intervals, and the immune responses were evaluated two weeks after the final immunization in mice. In a guinea pig model of ocular infection animals were immunized in the same manner as the mice, and protection against challenge was assessed two weeks after the last immunization. N-PmpC was successfully expressed within BGs and delivery to the ocular mucosa was well tolerated without signs of inflammation. N-PmpC-specific mucosal IgA levels in tears yielded significantly increased levels in the group immunized via the conjunctiva compared with the subcutaneously immunized mice. Immunization with N-PmpC EcN BGs via both immunization routes prompted the establishment of an N-PmpC-specific IFNγ immune response. Immunization via the conjunctiva resulted in a decrease in intensity of the transitional inflammatory reaction in conjunctiva of challenged guinea pigs compared with subcutaneously and non-immunized animals. The delivery of the chlamydial subunit vaccine to the ocular mucosa using a particulate carrier, such as BGs, induced both humoral and cellular immune responses. Further investigations are needed to improve the immunization scheme and dosage.


Subject(s)
Adhesins, Bacterial/immunology , Chlamydia trachomatis/immunology , Drug Carriers/chemistry , Eye/immunology , Mucous Membrane/immunology , Particulate Matter/chemistry , Vaccines, Subunit/immunology , Animals , Blotting, Western , Cell Proliferation , Conjunctiva/immunology , Disease Models, Animal , Epitopes , Escherichia coli/metabolism , Eye/microbiology , Eye/pathology , Female , Guinea Pigs , Immunization , Immunoglobulin A/metabolism , Immunoglobulin G/blood , Injections, Subcutaneous , Interferon-gamma/metabolism , Interleukin-4/metabolism , Mice, Inbred BALB C , Mucous Membrane/microbiology , Mucous Membrane/pathology , Recombinant Proteins/metabolism , Spleen/pathology , Tears/metabolism , Trachoma/immunology , Trachoma/microbiology , Trachoma/pathology , Trachoma/prevention & control
14.
Drug Des Devel Ther ; 9: 3741-54, 2015.
Article in English | MEDLINE | ID: mdl-26229437

ABSTRACT

To target chronic inflammatory ocular surface diseases, a drug delivery platform is needed that is safe, possesses immunomodulatory properties, and can be used either for drug delivery, or as a foreign antigen carrier. A new therapeutic approach that we have previously proposed uses nonliving bacterial ghosts (BGs) as a carrier-delivery system which can be engineered to carry foreign antigens and/or be loaded with therapeutic drugs. The parent strain chosen for development of our BG delivery system is the probiotic Escherichia coli strain Nissle 1917 (EcN), whose intrinsic properties trigger the innate immune system with the flagella and fimbriae used to attach and stimulate epithelial cells. In previous studies, we have shown that EcN BGs are safe for the ocular surface route, but evidence that EcN BGs retain flagella and fimbriae after transformation, has never been visually confirmed. In this study, we used different visualization techniques to determine whether flagella and fimbriae are retained on EcN BGs engineered either for drug delivery or as a foreign antigen carrier. We have also shown by immunoelectron microscopy that EcN retains two foreign antigens after processing to become EcN BGs. Furthermore, we demonstrated that BGs derived from EcN and expressing a foreign antigen attachment to conjunctival epithelial cells in vitro without causing reduced cell viability. These results are an important step in constructing a delivery system based on a nonliving probiotic that is suitable for use in ocular surface diseases pairing immunomodulation and targeted delivery.


Subject(s)
Antigens, Bacterial/administration & dosage , Drug Delivery Systems , Epithelial Cells/drug effects , Escherichia coli/chemistry , Cell Survival/drug effects , Cells, Cultured , Conjunctiva/cytology , Conjunctiva/drug effects , Epithelial Cells/metabolism , Humans , Microscopy, Immunoelectron , Probiotics/chemistry , Surface Properties
15.
J Infect Dis ; 211(4): 613-22, 2015 Feb 15.
Article in English | MEDLINE | ID: mdl-25193982

ABSTRACT

BACKGROUND: Coxsackievirus B3 (CVB3) is a major heart pathogen against which no therapy exists to date. The potential of a combination treatment consisting of a proteinaceous virus receptor trap and an RNA interference-based component to prevent CVB3-induced myocarditis was investigated. METHODS AND RESULTS: A soluble variant of the extracellular domain of the coxsackievirus-adenovirus receptor (sCAR-Fc) was expressed from an adenoviral vector and 2 short hairpin RNAs (shRdRp2.4) directed against CVB3 were delivered by an adeno-associated virus (AAV) vector. Cell culture experiments revealed additive antiviral activity of the combined application. In a CVB3-induced mouse myocarditis model, both components applied individually significantly reduced inflammation and viral load in the heart. The combination exerted an additive antiviral effect and reduced heart pathology. Hemodynamic measurement revealed that infection with CVB3 resulted in impaired heart function, as illustrated by a drastically reduced cardiac output and impaired contractility and relaxation. Treatment with either sCAR-Fc or shRdRp2.4 significantly improved these parameters. Importantly, the combination of both components led to a further significant improvement of heart function. CONCLUSIONS: Combination of sCAR-Fc and shRdRp2.4 exerted additive effects and was significantly more effective than either of the single treatments in inhibiting CVB3-induced myocarditis and preventing cardiac dysfunction.


Subject(s)
Antiviral Agents/pharmacology , Coxsackievirus Infections/drug therapy , Enterovirus B, Human/drug effects , Genetic Therapy/methods , Myocarditis/drug therapy , RNA Interference , Animals , Antiviral Agents/metabolism , Coxsackievirus Infections/virology , Disease Models, Animal , Dose-Response Relationship, Drug , HeLa Cells , Humans , Male , Mice , Mice, Inbred BALB C , Myocarditis/virology , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Receptors, Virus/genetics , Receptors, Virus/metabolism , Viral Load/drug effects
16.
Invest Ophthalmol Vis Sci ; 54(9): 6326-33, 2013 Sep 24.
Article in English | MEDLINE | ID: mdl-23920373

ABSTRACT

PURPOSE: For the successful topical administration of drugs or vaccines to treat ocular surface diseases, efficient and well-tolerated delivery systems/carriers for conjunctival delivery are crucial in the development of new treatment strategies. The present study investigated the efficiency of internalization of bacterial ghosts (BGs) produced from probiotic Escherichia coli Nissle 1917 (EcN) by human conjunctival epithelial (HCjE) cell line, the EcN BGs cytotoxicity for HCjE cells, and in vivo uptake of EcN BGs by conjunctival guinea pig epithelial cells. METHODS: The uptake of EcN BGs by HCjE cells was analyzed by laser scanning microscopy and flow cytometry. Immunohistochemistry was used to localize the EcN BGs in the guinea pig conjunctival tissue. Cytotoxicity of EcN BGs on HCjE cells was evaluated by measurement of LDH. RESULTS: Laser scanning microscopy and flow cytometry revealed that EcN BGs internalization by HCjE cells was time- and dose dependent. No cytotoxic effect on HCjE cells was observed after EcN BGs inoculation for 30 and 120 minutes, as well as 24 hours. In addition, the uptake of EcN BGs was detected in the conjunctival cells after in vivo administration of EcN BGs into the eye of the guinea pig. CONCLUSIONS: The findings that EcN BGs are nontoxic and effectively internalized in vitro by human and in vivo by guinea pig conjunctival cells comprise an important contribution to the future use of BGs as a system for conjunctival delivery of drugs and vaccines, either to treat or prevent ocular surface diseases.


Subject(s)
Conjunctiva/microbiology , Conjunctival Diseases/drug therapy , Epithelial Cells/drug effects , Escherichia coli , Probiotics/pharmacokinetics , Animals , Cell Line , Conjunctiva/metabolism , Conjunctiva/pathology , Conjunctival Diseases/metabolism , Conjunctival Diseases/pathology , Drug Delivery Systems , Epithelial Cells/metabolism , Epithelial Cells/pathology , Flow Cytometry , Guinea Pigs , Humans , Microscopy, Confocal , Probiotics/administration & dosage
17.
PLoS One ; 8(4): e60682, 2013.
Article in English | MEDLINE | ID: mdl-23637758

ABSTRACT

BACKGROUND: In a quest for a needle-free vaccine administration strategy, we evaluated the ocular conjunctiva as an alternative mucosal immunization route by profiling and comparing the local and systemic immune responses to the subcutaneous or conjunctival administration of tetanus toxoid (TTd), a model antigen. MATERIALS AND METHODS: BALB/c and C57BL/6 mice were immunized either subcutaneously with TTd alone or via the conjunctiva with TTd alone, TTd mixed with 2% glycerol or TTd with merthiolate-inactivated whole-cell B. pertussis (wBP) as adjuvants. Mice were immunized on days 0, 7 and 14 via both routes, and an evaluation of the local and systemic immune responses was performed two weeks after the last immunization. Four weeks after the last immunization, the mice were challenged with a lethal dose (2 × LD50) of tetanus toxin. RESULTS: The conjunctival application of TTd in BALB/c mice induced TTd-specific secretory IgA production and skewed the TTd-specific immune response toward a Th1/Th17 profile, as determined by the stimulation of IFNγ and IL-17A secretion and/or the concurrent pronounced reduction of IL-4 secretion, irrespective of the adjuvant. In conjunctivaly immunized C57BL/6 mice, only TTd administered with wBP promoted the establishment of a mixed Th1/Th17 TTd-specific immune response, whereas TTd alone or TTd in conjunction with glycerol initiated a dominant Th1 response against TTd. Immunization via the conjunctiva with TTd plus wBP adjuvant resulted in a 33% survival rate of challenged mice compared to a 0% survival rate in non-immunized animals (p<0.05). CONCLUSION: Conjunctival immunization with TTd alone or with various adjuvants induced TTd-specific local and systemic immune responses, predominantly of the Th1 type. The strongest immune responses developed in mice that received TTd together with wBP, which implies that this alternative route might tailor the immune response to fight intracellular bacteria or viruses more effectively.


Subject(s)
Antigens, Bacterial/immunology , Conjunctiva/immunology , Immunity, Mucosal/immunology , Immunization , Tetanus Toxoid/immunology , Adjuvants, Immunologic , Animals , Antibodies, Bacterial/blood , Antibodies, Bacterial/immunology , Antibody Formation/drug effects , Antibody Formation/immunology , B-Lymphocytes/cytology , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , Bordetella pertussis/immunology , Cell Proliferation/drug effects , Conjunctiva/pathology , Cytokines/metabolism , Female , Immunity, Mucosal/drug effects , Immunoglobulin A, Secretory/blood , Immunoglobulin A, Secretory/metabolism , Immunoglobulin G/blood , Lymph Nodes/cytology , Lymph Nodes/drug effects , Lymph Nodes/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Subcutaneous Tissue/drug effects , Subcutaneous Tissue/immunology , Submandibular Gland/cytology , Tears/immunology , Tetanus Toxin/toxicity , Th1 Cells/cytology , Th1 Cells/drug effects , Th1 Cells/immunology
18.
Mol Ther ; 21(5): 924-33, 2013 May.
Article in English | MEDLINE | ID: mdl-23439498

ABSTRACT

Insertion of completely complementary microRNA (miR) target sites (miRTS) into a transgene has been shown to be a valuable approach to specifically repress transgene expression in non-targeted tissues. miR-122TS have been successfully used to silence transgene expression in the liver following systemic application of cardiotropic adeno-associated virus (AAV) 9 vectors. For miR-206-mediated skeletal muscle-specific silencing of miR-206TS-bearing AAV9 vectors, however, we found this approach failed due to the expression of another member (miR-1) of the same miR family in heart tissue, the intended target. We introduced single-nucleotide substitutions into the miR-206TS and searched for those which prevented miR-1-mediated cardiac repression. Several mutated miR-206TS (m206TS), in particular m206TS-3G, were resistant to miR-1, but remained fully sensitive to miR-206. All these variants had mismatches in the seed region of the miR/m206TS duplex in common. Furthermore, we found that some m206TS, containing mismatches within the seed region or within the 3' portion of the miR-206, even enhanced the miR-206- mediated transgene repression. In vivo expression of m206TS-3G- and miR-122TS-containing transgene of systemically applied AAV9 vectors was strongly repressed in both skeletal muscle and the liver but remained high in the heart. Thus, site-directed mutagenesis of miRTS provides a new strategy to differentiate transgene de-targeting of related miRs.


Subject(s)
Dependovirus/physiology , Gene Expression Regulation , Gene Silencing , Genetic Vectors/genetics , MicroRNAs/genetics , Muscle, Skeletal/metabolism , Transgenes , Base Pairing , Base Sequence , Binding Sites , Cell Line , Gene Order , Gene Transfer Techniques , Genes, Reporter , Genetic Vectors/metabolism , Humans , MicroRNAs/metabolism , Mutagenesis, Site-Directed , Myocardium/metabolism , Organ Specificity/genetics , Viral Tropism
19.
Mol Vis ; 18: 2717-25, 2012.
Article in English | MEDLINE | ID: mdl-23233782

ABSTRACT

PURPOSE: Evaluating cytokine profiles in tears could shed light on the pathogenesis of various ocular surface diseases. When collecting tears with the methods currently available, it is often not possible to avoid the tear reflex, which may give a different cytokine profile compared to basal tears. More importantly, tear collection with glass capillaries, the most widely used method for taking samples and the best method for avoiding tear reflex, is impractical for remote area field studies because it is tedious and time-consuming for health workers, who cannot collect tears from a large number of patients with this method in one day. Furthermore, this method is uncomfortable for anxious patients and children. Thus, tears are frequently collected using ophthalmic sponges. These sponges have the advantage that they are well tolerated by the patient, especially children, and enable standardization of the tear collection volume. The aim of this study was to compare various ophthalmic sponges and extraction buffers to optimize the tear collection method for field studies for subsequent quantification of cytokines in tears using the Luminex technology. METHODS: Three ophthalmic sponges, Merocel, Pro-ophta, and Weck-Cel, were tested. Sponges were presoaked with 25 cytokines/chemokines of known concentrations and eluted with seven different extraction buffers (EX1-EX7). To assess possible interference in the assay from the sponges, two standard curves were prepared in parallel: 1) cytokines of known concentrations with the extraction buffers and 2) cytokines of known concentrations loaded onto the sponges with the extraction buffers. Subsequently, a clinical assessment of the chosen sponge-buffer combination was performed with tears collected from four healthy subjects using 1) aspiration and 2) sponges. To quantify cytokine/chemokine recovery and the concentration in the tears, a 25-plex Cytokine Panel and the Luminex xMap were used. This platform enables simultaneous measurement of proinflammatory cytokines, Th1/Th2 distinguishing cytokines, nonspecific acting cytokines, and chemokines. RESULTS: WE DEMONSTRATED THE FOLLOWING: (i) 25 cytokines/chemokines expressed highly variable interactions with buffers and matrices. Several buffers enabled recovery of similar cytokine values (regulated and normal T cell expressed and secreted [RANTES], interleukin [IL]-13, IL-6, IL-8, IL-2R, and granulocyte-macrophage colony-stimulating factor [GM-CSF]); others were highly variable (monocyte chemotactic protein-1 [MCP-1], monokine induced by interferon-gamma [MIG], IL-1ß, IL-4, IL-7, and eotaxin). (ii) Various extraction buffers displayed significantly different recovery rates on the same sponge for the same cytokine/chemokine. (iii) The highest recovery rates were obtained with the Merocel ophthalmic sponge except for tumor necrosis factor-α: the Weck-Cel ophthalmic sponge showed the best results, either with cytokine standards loaded onto sponges or with tears collected from the inner canthus of the eye, using the sponge. (iv) IL-5, IL-10, and interferon-α were not detected in any tear sample from four normal human subjects. Twenty-two cytokines/chemokines that we detected were extracted from the Merocel sponge to a satisfactory recovery percentage. The recovery of IL-7 was significantly lower in the extracted Merocel sponge compared to the diluted tear samples. The cytokine/chemokine extraction from tears showed the same pattern of extraction that we observed for extracting the standards. CONCLUSIONS: Simultaneous measurement of various cytokines using ophthalmic sponges yielded diverse results for various cytokines as the level of extraction differs noticeably for certain cytokines. A second set of controls (standard curves "with sponges") should be used to delineate the extent of extraction for each cytokine to be analyzed. Many cytokines/chemokines were detected in tear samples collected with the Merocel sponge, including many that have been implicated in ocular surface disease. Luminex detection of cytokine/chemokine profiles of tears collected with Merocel sponges and extracted with buffer EX1 may be useful in clinical studies, for example, to assess cytokine profiles evaluation in ocular surface diseases.


Subject(s)
Cytokines/analysis , Specimen Handling/standards , Tears/chemistry , Adsorption , Adult , Buffers , Calibration , Female , Formaldehyde , Humans , Polyvinyl Alcohol , Reference Standards , Reproducibility of Results , Sensitivity and Specificity , Specimen Handling/methods
20.
Vaccine ; 28(2): 463-9, 2009 Dec 11.
Article in English | MEDLINE | ID: mdl-19836478

ABSTRACT

A conformationally biased, agonist of human C5a(65-74) (EP67) was assessed for its adjuvant activities in vitro and in vivo. EP67 induced the release of the inflammatory (Th1) type cytokines from C5a receptor (CD88)-bearing antigen presenting cells (APC). EP67 did not induce the release of these cytokines from splenic APCs obtained from C5a receptor knockouts (CD88(-/-)). Serum from mice immunized with EP67-ovalbumin (OVA) contained high OVA-specific antibody (Ab) titers [IgG1, IgG2a (IGg2c), IgG2b]. Mice receiving OVA alone produced only IgG1 Abs, indicating the ability of EP67 to induce a Th1-like Ab class switch. Spleen cell cultures from wild type mice but not CD88(-/-) mice showed an enhanced OVA-specific proliferative response in vitro. These results indicate the ability of EP67 to drive a Th1-mediated immune response and its potential use as a unique adjuvant.


Subject(s)
Adjuvants, Immunologic/pharmacology , Complement C5a/agonists , Glycoconjugates/pharmacology , Vaccines/immunology , Adjuvants, Immunologic/chemical synthesis , Adjuvants, Immunologic/chemistry , Animals , Female , Glycoconjugates/chemical synthesis , Glycoconjugates/chemistry , Humans , Immune System/drug effects , Mice , Mice, Inbred C57BL , Vaccines/chemistry
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