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1.
Viruses ; 15(7)2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37515169

RESUMO

HSV-1 disease is a significant public health burden causing orofacial, genital, cornea, and brain infection. We previously reported that a trivalent HSV-2 gC2, gD2, gE2 nucleoside-modified mRNA-lipid nanoparticle (LNP) vaccine provides excellent protection against vaginal HSV-1 infection in mice. Here, we evaluated whether this HSV-2 gC2, gD2, gE2 vaccine is as effective as a similar HSV-1 mRNA LNP vaccine containing gC1, gD1, and gE1 in the murine lip and genital infection models. Mice were immunized twice with a total mRNA dose of 1 or 10 µg. The two vaccines produced comparable HSV-1 neutralizing antibody titers, and surprisingly, the HSV-2 vaccine stimulated more potent CD8+ T-cell responses to gE1 peptides than the HSV-1 vaccine. Both vaccines provided complete protection from clinical disease in the lip model, while in the genital model, both vaccines prevented death and genital disease, but the HSV-1 vaccine reduced day two vaginal titers slightly better at the 1 µg dose. Both vaccines prevented HSV-1 DNA from reaching the trigeminal or dorsal root ganglia to a similar extent. We conclude that the trivalent HSV-2 mRNA vaccine provides outstanding protection against HSV-1 challenge at two sites and may serve as a universal prophylactic vaccine for HSV-1 and HSV-2.


Assuntos
Herpes Genital , Herpesvirus Humano 1 , Feminino , Animais , Camundongos , Herpesvirus Humano 2/genética , Herpesvirus Humano 1/genética , Herpes Genital/prevenção & controle , Nucleosídeos , Anticorpos Neutralizantes , Proteínas do Envelope Viral , Anticorpos Antivirais , RNA Mensageiro/genética
2.
Viruses ; 15(5)2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37243234

RESUMO

Herpes simplex virus type 2 (HSV-2) is a leading cause of genital ulcer disease and a major risk factor for acquisition and transmission of HIV. Frequent recurrent genital lesions and concerns about transmitting infection to intimate partners affect the quality of life of infected individuals. Therapeutic vaccines are urgently needed to reduce the frequency of genital lesions and transmission. S-540956 is a novel vaccine adjuvant that contains CpG oligonucleotide ODN2006 annealed to its complementary sequence and conjugated to a lipid that targets the adjuvant to lymph nodes. Our primary goal was to compare S-540956 administered with HSV-2 glycoprotein D (gD2) with no treatment in a guinea pig model of recurrent genital herpes (studies 1 and 2). Our secondary goals were to compare S-540956 with oligonucleotide ODN2006 (study1) or glucopyranosyl lipid A in a stable oil-in-water nano-emulsion (GLA-SE) (study 2). gD2/S-540956 reduced the number of days with recurrent genital lesions by 56%, vaginal shedding of HSV-2 DNA by 49%, and both combined by 54% compared to PBS, and was more efficacious than the two other adjuvants. Our results indicate that S-540956 has great potential as an adjuvant for a therapeutic vaccine for genital herpes, and merits further evaluation with the addition of potent T cell immunogens.


Assuntos
Herpes Genital , Vacinas , Feminino , Cobaias , Animais , Herpes Genital/prevenção & controle , Herpesvirus Humano 2/genética , Anticorpos Neutralizantes , Anticorpos Antivirais , Qualidade de Vida , Proteínas do Envelope Viral , Adjuvantes Imunológicos , Genitália , Linfonodos , DNA
3.
Viruses ; 14(3)2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-35336946

RESUMO

The toxicity of mRNA-lipid nanoparticle (LNP) vaccines depends on the total mRNA-LNP dose. We established that the maximum tolerated dose of our trivalent mRNA-LNP genital herpes vaccine was 10 µg/immunization in mice. We then evaluated one of the mRNAs, gD2 mRNA-LNP, to determine how much of the 10 µg total dose to assign to this immunogen. We immunized mice with 0.3, 1.0, 3.0, or 10 µg of gD2 mRNA-LNP and measured serum IgG ELISA, neutralizing antibodies, and antibodies to six crucial gD2 epitopes involved in virus entry and spread. Antibodies to crucial gD2 epitopes peaked at 1 µg, while ELISA and neutralizing titers continued to increase at higher doses. The epitope results suggested no immunologic benefit above 1 µg of gD2 mRNA-LNP, while ELISA and neutralizing titers indicated higher doses may be useful. We challenged the gD2 mRNA-immunized mice intravaginally with HSV-2. The 1-µg dose provided total protection, confirming the epitope studies, and supported assigning less than one-third of the trivalent vaccine maximum dose of 10 µg to gD2 mRNA-LNP. Epitope mapping as performed in mice can also be accomplished in phase 1 human trials to help select the optimum dose of each immunogen in a multivalent vaccine.


Assuntos
Herpes Genital , Vacinas , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Herpes Genital/prevenção & controle , Herpesvirus Humano 2/genética , Lipossomos , Camundongos , Nanopartículas , RNA Mensageiro/genética , Proteínas do Envelope Viral/genética
4.
J Clin Invest ; 131(23)2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34618692

RESUMO

Nucleoside-modified mRNA vaccines have gained global attention because of COVID-19. We evaluated a similar vaccine approach for preventing a chronic, latent genital infection rather than an acute respiratory infection. We used animal models to compare an HSV-2 trivalent nucleoside-modified mRNA vaccine with the same antigens prepared as proteins, with an emphasis on antigen-specific memory B cell responses and immune correlates of protection. In guinea pigs, serum neutralizing-antibody titers were higher at 1 month and declined far less by 8 months in mRNA- compared with protein-immunized animals. Both vaccines protected against death and genital lesions when infected 1 month after immunization; however, protection was more durable in the mRNA group compared with the protein group when infected after 8 months, an interval representing greater than 15% of the animal's lifespan. Serum and vaginal neutralizing-antibody titers correlated with protection against infection, as measured by genital lesions and vaginal virus titers 2 days after infection. In mice, the mRNA vaccine generated more antigen-specific memory B cells than the protein vaccine at early times after immunization that persisted for up to 1 year. High neutralizing titers and robust B cell immune memory likely explain the more durable protection by the HSV-2 mRNA vaccine.


Assuntos
Herpes Genital , Herpesvirus Humano 2/imunologia , Memória Imunológica , Células B de Memória/imunologia , RNA Viral/imunologia , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , COVID-19/imunologia , COVID-19/prevenção & controle , Modelos Animais de Doenças , Feminino , Cobaias , Herpes Genital/imunologia , Herpes Genital/prevenção & controle , SARS-CoV-2/imunologia , Vacinas de mRNA
5.
PLoS Pathog ; 16(7): e1008795, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32716975

RESUMO

HSV-1 causes 50% of first-time genital herpes infections in resource-rich countries and affects 190 million people worldwide. A prophylactic herpes vaccine is needed to protect against genital infections by both HSV-1 and HSV-2. Previously our laboratory developed a trivalent vaccine that targets glycoproteins C, D, and E present on the HSV-2 virion. We reported that this vaccine protects animals from genital disease and recurrent virus shedding following lethal HSV-2 challenge. Importantly the vaccine also generates cross-reactive antibodies that neutralize HSV-1, suggesting it may provide protection against HSV-1 infection. Here we compared the efficacy of this vaccine delivered as protein or nucleoside-modified mRNA immunogens against vaginal HSV-1 infection in mice. Both the protein and mRNA vaccines protected mice from HSV-1 disease; however, the mRNA vaccine provided better protection as measured by lower vaginal virus titers post-infection. In a second experiment, we compared protection provided by the mRNA vaccine against intravaginal challenge with HSV-1 or HSV-2. Vaccinated mice were totally protected against death, genital disease and infection of dorsal root ganglia caused by both viruses, but somewhat better protected against vaginal titers after HSV-2 infection. Overall, in the two experiments, the mRNA vaccine prevented death and genital disease in 54/54 (100%) mice infected with HSV-1 and 20/20 (100%) with HSV-2, and prevented HSV DNA from reaching the dorsal root ganglia, the site of virus latency, in 29/30 (97%) mice infected with HSV-1 and 10/10 (100%) with HSV-2. We consider the HSV-2 trivalent mRNA vaccine to be a promising candidate for clinical trials for prevention of both HSV-1 and HSV-2 genital herpes.


Assuntos
Proteção Cruzada/imunologia , Herpes Genital , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/imunologia , Vacinas contra Herpesvirus/imunologia , Latência Viral/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Feminino , Herpes Genital/virologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro , Proteínas do Envelope Viral/imunologia
6.
Hum Vaccin Immunother ; 16(9): 2109-2113, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32347775

RESUMO

A vaccine to prevent genital herpes is an unmet public health need. We previously reported that a trivalent vaccine containing herpes simplex virus type 2 (HSV-2) glycoproteins C, D, and E (gC2, gD2, gE2) produced in baculovirus and administered with CpG/alum as adjuvants blocks immune evasion mediated by gC2 and gE2 and virus entry by gD2. The vaccine protected guinea pigs against HSV-2 vaginal infection. We evaluated whether the HSV-2 vaccine cross-protects against HSV-1 because many first-time genital herpes infections are now caused by HSV-1. Guinea pigs were mock immunized or immunized with the trivalent vaccine and challenged intravaginally with a different HSV-1 isolate in two experiments. Guinea pigs immunized with the trivalent vaccine developed genital lesions on fewer days than the mock group: 2/477 (0.4%) days compared to 15/424 (3.5%) in experiment one, and 0/135 days compared to 17/135 (12.6%) in experiment two (both P < .001). No animal in the trivalent group had HSV-2 DNA detected in vaginal secretions: 0/180 days for trivalent compared to 4/160 (2.5%) for mock (P < .05) in experiment one, and 0/65 days for trivalent compared to 4/65 (6%) for mock in experiment two. Therefore, a vaccine designed to prevent HSV-2 also protects against HSV-1 genital infection.


Assuntos
Herpes Genital , Herpes Simples , Herpesvirus Humano 1 , Vacinas , Animais , Feminino , Genitália , Cobaias , Herpes Genital/prevenção & controle , Herpesvirus Humano 2 , Proteínas do Envelope Viral
7.
Transl Res ; 220: 138-152, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32272093

RESUMO

Genital herpes increases the risk of acquiring and transmitting Human Immunodeficiency Virus (HIV), is a source of anxiety for many about transmitting infection to intimate partners, and is life-threatening to newborns. A vaccine that prevents genital herpes infection is a high public health priority. An ideal vaccine will prevent both genital lesions and asymptomatic subclinical infection to reduce the risk of inadvertent transmission to partners, will be effective against genital herpes caused by herpes simplex virus types 1 and 2 (HSV-1, HSV-2), and will protect against neonatal herpes. Three phase 3 human trials were performed over the past 20 years that used HSV-2 glycoproteins essential for virus entry as immunogens. None achieved its primary endpoint, although each was partially successful in either delaying onset of infection or protecting a subset of female subjects that were HSV-1 and HSV-2 uninfected against HSV-1 genital infection. The success of future vaccine candidates may depend on improving the predictive value of animal models by requiring vaccines to achieve near-perfect protection in these models and by using the models to better define immune correlates of protection. Many vaccine candidates are under development, including DNA, modified mRNA, protein subunit, killed virus, and attenuated live virus vaccines. Lessons learned from prior vaccine studies and select candidate vaccines are discussed, including a trivalent nucleoside-modified mRNA vaccine that our laboratory is pursuing. We are optimistic that an effective vaccine for prevention of genital herpes will emerge in this decade.


Assuntos
Herpes Genital/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Herpes Genital/imunologia , Humanos , Evasão da Resposta Imune
8.
Health Econ ; 28(6): 736-747, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31020746

RESUMO

Individuals often have biased perceptions about their peers' behavior. We use an economic equilibrium analysis to study the role social norms play in substance use decisions. Using a nationally representative dataset, we estimate the effect of misperception about friends' alcohol, smoking, and marijuana use on consumption of these substances by youths in grades 7-12. Overestimation of friend's substance use significantly increases adolescent's own use approximately 1 year later, and the estimated effect is robust across specifications including individual-level fixed effects regression. The effect size is bigger for boys than for girls. The estimates for those who initially underestimated the norm suggest the possibility of a rebound/boomerang effect.


Assuntos
Comportamento do Adolescente , Normas Sociais , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Criança , Bases de Dados Factuais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Inquéritos e Questionários
9.
Front Microbiol ; 9: 2116, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30298056

RESUMO

The thermophilic, endospore-forming genus of Geobacillus has historically been associated with spoilage of canned food. However, in recent years it has become the subject of much attention due its biotechnological potential in areas such as enzyme and biofuel applications. One aspect of this genus that has not been fully explored or realized is its use as a source of novel forms of the ribosomally synthesized antimicrobial peptides known as bacteriocins. To date only two bacteriocins have been fully characterized within this genus, i.e., Geobacillin I and II, with only a small number of others partially characterized. Here we bioinformatically investigate the potential of this genus as a source of novel bacteriocins through the use of the in silico screening software BAGEL3, which scans publically available genomes for potential bacteriocin gene clusters. In this study we examined the association of bacteriocin gene presence with niche and phylogenetic position within the genus. We also identified a number of candidates from multiple bacteriocin classes which may be promising antimicrobial candidates when investigated in vitro in future studies.

10.
Bone ; 109: 56-60, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29320714

RESUMO

Mesenteric heterotopic ossification (MHO) is very rare and occurs in mid- to late-adulthood, usually in the context of prior abdominal surgery. The mechanisms of MHO are unknown. Here we describe the case of a 72-year-old man with MHO. Standard histological staining revealed that MHO occurred through an endochondral process. By comparison to known mutations in genetic conditions of HO such as fibrodysplasia ossificans progressiva (FOP) and progressive osseous heteroplasia (POH), DNA sequencing analysis demonstrated the presence of a commonly occurring heterozygous synonymous polymorphism (c.690G>A; E230E) in the causative gene for FOP (ACVR1/ALK2). However, no frameshift, missense, or nonsense mutations in ACVR1, or in the causative gene for POH (GNAS), were found. Although genetic predisposition may play a role in MHO, our data suggest that mutations which occur in known hereditary conditions of HO are not the primary cause.


Assuntos
Ossificação Heterotópica/genética , Ossificação Heterotópica/patologia , Idoso , Doenças Ósseas Metabólicas/genética , Doenças Ósseas Metabólicas/patologia , Predisposição Genética para Doença , Humanos , Masculino , Miosite Ossificante/genética , Miosite Ossificante/patologia , Análise de Sequência de DNA , Dermatopatias Genéticas/genética , Dermatopatias Genéticas/patologia
11.
Bone ; 109: 61-64, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29305336

RESUMO

Non-hereditary heterotopic ossification (NHHO) may occur after musculoskeletal trauma, central nervous system (CNS) injury, or surgery. We previously described circulating osteogenic precursor (COP) cells as a bone marrow-derived type 1 collagen+CD45+subpopulation of mononuclear adherent cells that are able of producing extraskeletal ossification in a murine in vivo implantation assay. In the current study, we performed a tissue analysis of COP cells in NHHO secondary to defined conditions, including traumatic brain injury, spinal cord injury, cerebrovascular accident, trauma without neurologic injury, and joint arthroplasty. All bone specimens revealed the presence of COP cells at 2-14 cells per high power field. COP cells were localized to early fibroproliferative and neovascular lesions of NHHO with evidence for their circulatory status supported by their presence near blood vessels in examined lesions. This study provides the first systematic evaluation of COP cells as a contributory histopathological finding associated with multiple forms of NHHO. These data support that circulating, hematopoietic-derived cells with osteogenic potential can seed inflammatory sites, such as those subject to soft tissue injury, and due to their migratory nature, may likely be involved in seeding sites distant to CNS injury.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Ossificação Heterotópica/patologia , Osteogênese/fisiologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas Traumáticas/metabolismo , Feminino , Imunofluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/metabolismo , Osteogênese/genética , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Adulto Jovem
12.
Virology ; 514: 124-133, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29175626

RESUMO

The lip scarification model of herpes simplex virus type 1 (HSV-1) infection can be used to study acute infection in the orofacial tissue and the establishment of viral latency. In this study, mice were inoculated with HSV-1 and tissue harvested during the acute phase of infection. Clinical presentation of classical open sores on the lip of infected mice was observed. We defined the histopathology, disease scores, and immune infiltration of the lower lip during the formation and resolution of the clinical lesions. Finally, the kinetics of virus replication and transport of viral genomes to the trigeminal ganglia were established. With the virological and pathologic events of acute infection defined, the HSV-1 lip scarification model can now be used to study primary HSV-1 infection, invasion of the trigeminal ganglia, and establishment of latency.


Assuntos
Herpes Simples/imunologia , Herpes Simples/patologia , Herpesvirus Humano 1/fisiologia , Lábio/virologia , Replicação Viral , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Replicação do DNA , Modelos Animais de Doenças , Herpes Simples/virologia , Herpesvirus Humano 1/genética , Humanos , Cinética , Lábio/imunologia , Lábio/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gânglio Trigeminal/imunologia , Gânglio Trigeminal/virologia , Latência Viral
13.
Genome Announc ; 5(43)2017 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-29074660

RESUMO

This paper reports the full genome sequence of the antimicrobial-producing bacterium Geobacillus stearothermophilus DSM 458, isolated in a sugar beet factory in Austria. In silico analysis reveals the presence of a number of novel bacteriocin biosynthetic genes.

14.
Emerg Top Life Sci ; 1(1): 55-63, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33525813

RESUMO

Antibiotics have revolutionised the treatment of infectious disease and improved the lives of billions of people worldwide over many decades. With the rise in antimicrobial resistance (AMR) and corresponding lack of antibiotic development, we find ourselves in dire need of alternative treatments. Bacteriocins are a class of bacterially produced, ribosomally synthesised, antimicrobial peptides that may be narrow or broad in their spectra of activity. Animal models have demonstrated the safety and efficacy of bacteriocins in treating a broad range of infections; however, one of the principal drawbacks has been their relatively narrow spectra when compared with small-molecule antibiotics. In an era where we are beginning to appreciate the role of the microbiota in human and animal health, the fact that bacteriocins cause much less collateral damage to the host microbiome makes them a highly desirable therapeutic. This review makes a case for the implementation of bacteriocins as therapeutic antimicrobials, either alone or in combination with existing antibiotics to alleviate the AMR crisis and to lessen the impact of antibiotics on the host microbiome.

15.
Front Microbiol ; 7: 461, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27092121

RESUMO

Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, which have the ability to kill or inhibit other bacteria. Many bacteriocins are produced by food grade lactic acid bacteria (LAB). Indeed, the prototypic bacteriocin, nisin, is produced by Lactococcus lactis, and is licensed in over 50 countries. With consumers becoming more concerned about the levels of chemical preservatives present in food, bacteriocins offer an alternative, more natural approach, while ensuring both food safety and product shelf life. Bacteriocins also show additive/synergistic effects when used in combination with other treatments, such as heating, high pressure, organic compounds, and as part of food packaging. These features are particularly attractive from the perspective of controlling sporeforming bacteria. Bacterial spores are common contaminants of food products, and their outgrowth may cause food spoilage or food-borne illness. They are of particular concern to the food industry due to their thermal and chemical resistance in their dormant state. However, when spores germinate they lose the majority of their resistance traits, making them susceptible to a variety of food processing treatments. Bacteriocins represent one potential treatment as they may inhibit spores in the post-germination/outgrowth phase of the spore cycle. Spore eradication and control in food is critical, as they are able to spoil and in certain cases compromise the safety of food by producing dangerous toxins. Thus, understanding the mechanisms by which bacteriocins exert their sporostatic/sporicidal activity against bacterial spores will ultimately facilitate their optimal use in food. This review will focus on the use of bacteriocins alone, or in combination with other innovative processing methods to control spores in food, the current knowledge and gaps therein with regard to bacteriocin-spore interactions and discuss future research approaches to enable spores to be more effectively targeted by bacteriocins in food settings.

16.
Dis Model Mech ; 7(5): 583-92, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24626990

RESUMO

A major medical challenge in the elderly is osteoporosis and the high risk of fracture. Telomere dysfunction is a cause of cellular senescence and telomere shortening, which occurs with age in cells from most human tissues, including bone. Telomere defects contribute to the pathogenesis of two progeroid disorders characterized by premature osteoporosis, Werner syndrome and dyskeratosis congenital. It is hypothesized that telomere shortening contributes to bone aging. We evaluated the skeletal phenotypes of mice with disrupted telomere maintenance mechanisms as models for human bone aging, including mutants in Werner helicase (Wrn(-/-)), telomerase (Terc(-/-)) and Wrn(-/-)Terc(-/-) double mutants. Compared with young wild-type (WT) mice, micro-computerized tomography analysis revealed that young Terc(-/-) and Wrn(-/-)Terc(-/-) mice have decreased trabecular bone volume, trabecular number and trabecular thickness, as well as increased trabecular spacing. In cortical bone, young Terc(-/-) and Wrn(-/-)Terc(-/-) mice have increased cortical thinning, and increased porosity relative to age-matched WT mice. These trabecular and cortical changes were accelerated with age in Terc(-/-) and Wrn(-/-)Terc(-/-) mice compared with older WT mice. Histological quantification of osteoblasts in aged mice showed a similar number of osteoblasts in all genotypes; however, significant decreases in osteoid, mineralization surface, mineral apposition rate and bone formation rate in older Terc(-/-) and Wrn(-/-)Terc(-/-) bone suggest that osteoblast dysfunction is a prominent feature of precocious aging in these mice. Except in the Wrn(-/-) single mutant, osteoclast number did not increase in any genotype. Significant alterations in mechanical parameters (structure model index, degree of anistrophy and moment of inertia) of the Terc(-/-) and Wrn(-/-)Terc(-/-) femurs compared with WT mice were also observed. Young Wrn(-/-)Terc(-/-) mice had a statistically significant increase in bone-marrow fat content compared with young WT mice, which remained elevated in aged double mutants. Taken together, our results suggest that Terc(-/-) and Wrn(-/-)Terc(-/-) mutants recapitulate the human bone aging phenotype and are useful models for studying age-related osteoporosis.


Assuntos
Osso e Ossos/patologia , Osteoporose/patologia , Telômero/patologia , Adiposidade , Animais , Medula Óssea/patologia , Reabsorção Óssea/patologia , Contagem de Células , Modelos Animais de Doenças , Humanos , Cinética , Camundongos , Mutação/genética , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteoclastos/patologia , Osteogênese , Fenótipo , RecQ Helicases/deficiência , RecQ Helicases/metabolismo , Telomerase/deficiência , Telomerase/metabolismo , Helicase da Síndrome de Werner
17.
J Neurovirol ; 19(4): 328-45, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23943467

RESUMO

Herpes simplex virus type 1 (HSV-1) is capable of causing a latent infection in sensory neurons that lasts for the lifetime of the host. The primary infection is resolved following the induction of the innate immune response that controls replication of the virus until the adaptive immune response can clear the active infection. HSV-1-specific CD8(+) T cells survey the ganglionic regions containing latently infected neurons and participate in preventing reactivation of HSV from latency. The long-term residence and migration dynamics of the T cells in the trigeminal ganglia appear to distinguish them from the traditional memory T cell subsets. Recently described tissue resident memory (TRM) T cells establish residence and survive for long periods in peripheral tissue compartments following antigen exposure. This review focuses on the immune system response to HSV-1 infection. Particular emphasis is placed on the evidence pointing to the HSV-1-specific CD8(+) T cells in the trigeminal belonging to the TRM class of memory T cells and the role of TRM cells in virus infection, pathogenesis, latency, and disease.


Assuntos
Herpes Simples/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Humanos , Memória Imunológica/imunologia , Simplexvirus/imunologia , Ativação Viral/imunologia , Latência Viral/imunologia
18.
J Mol Med (Berl) ; 91(12): 1421-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23974989

RESUMO

UNLABELLED: Bone tissue adapts to its functional environment by optimizing its morphology for mechanical demand. Among the mechanosensitive cells that recognize and respond to forces in the skeleton are osteocytes, osteoblasts, and mesenchymal progenitor cells (MPCs). Therefore, the ability to use mechanical signals to improve bone health through exercise and devices that deliver mechanical signals is an attractive approach to age-related bone loss; however, the extracellular or circulating mediators of such signals are largely unknown. Using SDS-PAGE separation of proteins secreted by MPCs in response to low-magnitude mechanical signals and in-gel trypsin digestion followed by HPLC and mass spectroscopy, we identified secreted proteins up-regulated by vibratory stimulation. We exploited a cell senescence-associated secretory phenotype screen and reasoned that a subset of vibration-induced proteins with diminished secretion by senescent MPCs will have the capacity to promote bone formation in vivo. We identified one such vibration-induced bone-enhancing (vibe) gene as R-spondin 1, a Wnt pathway modulator, and demonstrated that it has the capacity to promote bone formation in three mouse models of age-related bone loss. By virtue of their secretory status, some vibe proteins may be candidates for pre-clinical development as anabolic agents for the treatment of osteoporosis. KEY MESSAGE: Mesenchymal stem cells respond to low magnitude mechanical signals (vibration). R-Spondin 1 is upregulated by mechanical signals and secreted. R-Spondin 1 promotes bone formation in three mouse models of osteoporosis.


Assuntos
Osteogênese , Osteoporose/metabolismo , Trombospondinas/metabolismo , Vibração , Animais , Expressão Gênica , Humanos , Imunofenotipagem , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Knockout , Osteogênese/genética , Osteoporose/genética , Fenótipo , Trombospondinas/genética
19.
Stem Cells ; 31(3): 607-11, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23193076

RESUMO

Age-related osteoporosis is characterized by a decrease in bone-forming capacity mediated by defects in the number and function of osteoblasts. An important cellular mechanism that may in part explain osteoblast dysfunction that occurs with aging is senescence of mesenchymal progenitor cells (MPCs). In the telomere-based Wrn(-/-) Terc(-/-) model of accelerated aging, the osteoporotic phenotype of these mice is also associated with a major decline in MPC differentiation into osteoblasts. To investigate the role of MPC aging as a cell-autonomous mechanism in senile bone loss, transplantation of young wild-type whole bone marrow into Wrn(-/-) Terc(-/-) mutants was performed and the ability of engrafted cells to differentiate into cells of the osteoblast lineage was assessed. We found that whole bone marrow transplantation in Wrn(-/-) Terc(-/-) mice resulted in functional engraftment of MPCs up to 42 weeks, which was accompanied by a survival advantage as well as delays in microarchitectural features of skeletal aging.


Assuntos
Envelhecimento/patologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Osteoporose/patologia , Animais , Diferenciação Celular/fisiologia , Senescência Celular/fisiologia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Análise de Sobrevida , Telômero/patologia
20.
Histopathology ; 61(6): 1168-73, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22882309

RESUMO

AIMS: Histomorphometric analysis is a widely used technique to assess changes in tissue structure and function. Commercially available programs that measure histomorphometric parameters can be cost-prohibitive. In this study, we compared an inexpensive method of histomorphometry to a current proprietary software program. METHODS AND RESULTS: Image J and Adobe Photoshop(®) were used to measure static and kinetic bone histomorphometric parameters. Photomicrographs of Goldner's trichrome-stained femurs were used to generate black-and-white image masks, representing bone and non-bone tissue, respectively, in Adobe Photoshop(®) . The masks were used to quantify histomorphometric parameters (bone volume, tissue volume, osteoid volume, mineralizing surface and interlabel width) in Image J. The resultant values obtained using Image J and the proprietary software were compared and differences found to be statistically non-significant. CONCLUSIONS: The wide-ranging use of histomorphometric analysis for assessing the basic morphology of tissue components makes it important to have affordable and accurate measurement options available for a diverse range of applications. Here we have developed and validated an approach to histomorphometry using commonly and freely available software that is comparable to a much more costly, commercially available software program.


Assuntos
Osso e Ossos/patologia , Técnicas Histológicas/métodos , Processamento de Imagem Assistida por Computador/métodos , Software , Animais , Densidade Óssea , Tamanho Celular , Corantes Fluorescentes , Humanos , Camundongos
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