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1.
Nat Commun ; 12(1): 763, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536429

RESUMO

Human and animal infections with bacteria of the genus Sarcina (family Clostridiaceae) are associated with gastric dilation and emphysematous gastritis. However, the potential roles of sarcinae as commensals or pathogens remain unclear. Here, we investigate a lethal disease of unknown etiology that affects sanctuary chimpanzees (Pan troglodytes verus) in Sierra Leone. The disease, which we have named "epizootic neurologic and gastroenteric syndrome" (ENGS), is characterized by neurologic and gastrointestinal signs and results in death of the animals, even after medical treatment. Using a case-control study design, we show that ENGS is strongly associated with Sarcina infection. The microorganism is distinct from Sarcina ventriculi and other known members of its genus, based on bacterial morphology and growth characteristics. Whole-genome sequencing confirms this distinction and reveals the presence of genetic features that may account for the unusual virulence of the bacterium. Therefore, we propose that this organism be considered the representative of a new species, named "Candidatus Sarcina troglodytae". Our results suggest that a heretofore unrecognized complex of related sarcinae likely exists, some of which may be highly virulent. However, the potential role of "Ca. S. troglodytae" in the etiology of ENGS, alone or in combination with other factors, remains a topic for future research.


Assuntos
Doenças dos Símios Antropoides/diagnóstico , Enfisema/diagnóstico , Gastrite/diagnóstico , Infecções por Bactérias Gram-Positivas/diagnóstico , Sarcina/genética , Animais , Doenças dos Símios Antropoides/microbiologia , DNA Bacteriano/análise , DNA Bacteriano/genética , Enfisema/microbiologia , Gastrite/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Humanos , Pan troglodytes , Sarcina/classificação , Sarcina/patogenicidade , Serra Leoa , Virulência/genética , Sequenciamento Completo do Genoma/métodos
2.
N Engl J Med ; 384(6): 541-549, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33567193

RESUMO

BACKGROUND: A safe and effective vaccine to prevent chronic hepatitis C virus (HCV) infection is a critical component of efforts to eliminate the disease. METHODS: In this phase 1-2 randomized, double-blind, placebo-controlled trial, we evaluated a recombinant chimpanzee adenovirus 3 vector priming vaccination followed by a recombinant modified vaccinia Ankara boost; both vaccines encode HCV nonstructural proteins. Adults who were considered to be at risk for HCV infection on the basis of a history of recent injection drug use were randomly assigned (in a 1:1 ratio) to receive vaccine or placebo on days 0 and 56. Vaccine-related serious adverse events, severe local or systemic adverse events, and laboratory adverse events were the primary safety end points. The primary efficacy end point was chronic HCV infection, defined as persistent viremia for 6 months. RESULTS: A total of 548 participants underwent randomization, with 274 assigned to each group. There was no significant difference in the incidence of chronic HCV infection between the groups. In the per-protocol population, chronic HCV infection developed in 14 participants in each group (hazard ratio [vaccine vs. placebo], 1.53; 95% confidence interval [CI], 0.66 to 3.55; vaccine efficacy, -53%; 95% CI, -255 to 34). In the modified intention-to-treat population, chronic HCV infection developed in 19 participants in the vaccine group and 17 in placebo group (hazard ratio, 1.66; 95% CI, 0.79 to 3.50; vaccine efficacy, -66%; 95% CI, -250 to 21). The geometric mean peak HCV RNA level after infection differed between the vaccine group and the placebo group (152.51×103 IU per milliliter and 1804.93×103 IU per milliliter, respectively). T-cell responses to HCV were detected in 78% of the participants in the vaccine group. The percentages of participants with serious adverse events were similar in the two groups. CONCLUSIONS: In this trial, the HCV vaccine regimen did not cause serious adverse events, produced HCV-specific T-cell responses, and lowered the peak HCV RNA level, but it did not prevent chronic HCV infection. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT01436357.).


Assuntos
Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/prevenção & controle , Imunogenicidade da Vacina , Vacinas contra Hepatite Viral/imunologia , Adenovirus dos Símios/genética , Adolescente , Adulto , Animais , Método Duplo-Cego , Feminino , Vetores Genéticos , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/imunologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pan troglodytes , Abuso de Substâncias por Via Intravenosa , Linfócitos T/imunologia , Vacinas Sintéticas/imunologia , Vacinas contra Hepatite Viral/efeitos adversos , Adulto Jovem
3.
Am J Primatol ; 83(2): e23228, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33400317

RESUMO

Respiratory illnesses, including COVID-19, present a serious threat to endangered wild chimpanzee (Pan troglodytes) populations. In some parts of sub-Saharan Africa, chimpanzee tracking is a popular tourism activity, offering visitors a chance to view apes in their natural habitats. Chimpanzee tourism is an important source of revenue and thus benefits conservation; however, chimpanzee tracking may also increase the risk of disease transmission from people to chimpanzees directly (e.g., via aerosol transmission) or indirectly (e.g., through the environment or via fomites). This study assessed how tourist behaviors might facilitate respiratory disease transmission at a chimpanzee tracking site in Kibale National Park, Uganda. We observed tourists, guides, and student interns from the time they entered the forest to view the chimpanzees until they left the forest and noted behaviors related to disease transmission. Common behaviors included coughing, sneezing, and urinating, which respectively occurred during 88.1%, 65.4%, and 36.6% of excursions. Per excursion, individuals touched their faces an average of 125.84 ± 34.45 times and touched large tree trunks or branches (which chimpanzees might subsequently touch) an average of 230.14 ± 108.66 times. These results show that many pathways exist by which pathogens might move from humans to chimpanzees in the context of tourism. Guidelines for minimizing the risk of such transmission should consider tourist behavior and the full range of modes by which pathogen transmission might occur between tourists and chimpanzees.


Assuntos
Doenças dos Símios Antropoides/etiologia , Pan troglodytes , Doenças Respiratórias/veterinária , Turismo , África Oriental , Animais , Doenças dos Símios Antropoides/transmissão , Doenças dos Símios Antropoides/virologia , Comportamento , Comportamento Animal , /virologia , Humanos , Doenças Respiratórias/etiologia , Doenças Respiratórias/virologia , /patogenicidade
5.
Nat Commun ; 12(1): 539, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483482

RESUMO

Humans maintain extensive social ties of varying preferences, providing a range of opportunities for beneficial cooperative exchange that may promote collective action and our unique capacity for large-scale cooperation. Similarly, non-human animals maintain differentiated social relationships that promote dyadic cooperative exchange, but their link to cooperative collective action is little known. Here, we investigate the influence of social relationship properties on male and female chimpanzee participations in a costly form of group action, intergroup encounters. We find that intergroup encounter participation increases with a greater number of other participants as well as when participants are maternal kin or social bond partners, and that these effects are independent from one another and from the likelihood to associate with certain partners. Together, strong social relationships between kin and non-kin facilitate group-level cooperation in one of our closest living relatives, suggesting that social bonds may be integral to the evolution of cooperation in our own species.


Assuntos
Comportamento Animal/fisiologia , Pan troglodytes/fisiologia , Comportamento Social , Predomínio Social , Animais , Comportamento Cooperativo , Feminino , Processos Grupais , Humanos , Masculino , Pan troglodytes/psicologia
6.
Anal Chem ; 93(3): 1677-1685, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33373190

RESUMO

Mass spectrometry imaging (MSI) has become an important tool for 2D profiling of biological tissues, allowing for the visualization of individual compound distributions in the sample. Based on this information, it is possible to investigate the molecular organization within any particular tissue and detect abnormal regions (such as tumor regions) and many other biologically relevant phenomena. However, the large number of compounds present in the spectra hinders the productive analysis of large MSI datasets when utilizing standard tools. The heterogeneity of samples makes exploratory visualization (a presentation of the general idea of the molecular and structural organization of the inspected tissues) challenging. Here, we explore the application of various dimensionality reduction techniques that have been used extensively in the visualization of hyperspectral images and the MSI data specifically, such as principal component analysis, independent component analysis, non-negative matrix factorization, t-distributed stochastic neighbor embedding, and uniform manifold approximation and projection. Further, we propose a new approach based on a combination of structure preserving visualization with nonlinear manifold embedding of normalized spectral data. This way, we aim to preserve as much spatially overlapping signals as possible while augmenting them with information on compositional (spectral) variation. The proposed approach can be used for exploratory visualization of MSI datasets without prior deep chemical or histological knowledge of the sample. Thus, different datasets can be visually compared employing the proposed method. The proposed approach allowed for the clear visualization of the molecular layer, granular layer, and white matter in chimpanzee and macaque cerebellum slices.


Assuntos
Encéfalo/metabolismo , Algoritmos , Animais , Feminino , Macaca mulatta , Masculino , Espectrometria de Massas , Pan troglodytes , Análise de Componente Principal
7.
Am J Phys Anthropol ; 174(1): 129-139, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32865237

RESUMO

OBJECTIVES: This study describes and demonstrates the functionalities and application of a new R package, morphomap, designed to extract shape information as semilandmarks in multiple sections, build cortical thickness maps, and calculate biomechanical parameters on long bones. METHODS: morphomap creates, from a single input (an oriented 3D mesh representing the long bone surface), multiple evenly spaced virtual sections. morphomap then directly and rapidly computes morphometric and biomechanical parameters on each of these sections. The R package comprises three modules: (a) to place semilandmarks on the inner and outer outlines of each section, (b) to extract cortical thicknesses for 2D and 3D morphometric mapping, and (c) to compute cross-sectional geometry. RESULTS: In this article, we apply morphomap to femora from Homo sapiens and Pan troglodytes to demonstrate its utility and show its typical outputs. morphomap greatly facilitates rapid analysis and functional interpretation of long bone form and should prove a valuable addition to the osteoarcheological analysis software toolkit. CONCLUSIONS: Long bone loading history is commonly retrodicted by calculating biomechanical parameters such as area moments of inertia, analyzing external shape and measuring cortical thickness. morphomap is a software written in the open source R environment, it integrates the main methodological approaches (geometric morphometrics, cortical morphometric maps, and cross-sectional geometry) used to parametrize long bones.


Assuntos
Diáfises/diagnóstico por imagem , Fêmur/diagnóstico por imagem , Imageamento Tridimensional/métodos , Software , Anatomia Transversal/métodos , Animais , Antropologia Física , Diáfises/anatomia & histologia , Fêmur/anatomia & histologia , Humanos , Pan troglodytes
8.
PLoS Biol ; 18(12): e3000971, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33383575

RESUMO

Chimpanzees (Pan troglodytes) are, along with bonobos, humans' closest living relatives. The advent of diffusion MRI tractography in recent years has allowed a resurgence of comparative neuroanatomical studies in humans and other primate species. Here we offer, in comparative perspective, the first chimpanzee white matter atlas, constructed from in vivo chimpanzee diffusion-weighted scans. Comparative white matter atlases provide a useful tool for identifying neuroanatomical differences and similarities between humans and other primate species. Until now, comprehensive fascicular atlases have been created for humans (Homo sapiens), rhesus macaques (Macaca mulatta), and several other nonhuman primate species, but never in a nonhuman ape. Information on chimpanzee neuroanatomy is essential for understanding the anatomical specializations of white matter organization that are unique to the human lineage.


Assuntos
Pan troglodytes/anatomia & histologia , Substância Branca/anatomia & histologia , Anatomia Artística/métodos , Animais , Atlas como Assunto , Encéfalo/anatomia & histologia , Mapeamento Encefálico/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/métodos , Masculino
9.
PLoS One ; 15(12): e0244092, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326497

RESUMO

In humans, neutrophil to lymphocyte ratio (NLR) has been used as a clinical tool in diagnosis and/or prognosis of a variety of cancers and medical conditions, as well as in measuring physiological stress over time. Given the close phylogenetic relationship and physical similarities between humans and apes, NLR may similarly be a useful diagnostic tool in assessing chimpanzee health. Only one study has examined NLR in apes, reporting that NLR increased with age and was affected by body-mass index and sex. In the current study, we examined changes in NLR data from longitudinal health records for 443 chimpanzees in two captive chimpanzee populations. Using these data, we analyzed intra-individual changes and inter-individual differences in NLR as a function of age, rearing history, and sex. Contrary to previous studies in humans and the one previous study in chimpanzees, NLR values did not change over a 10-year timespan within individual chimpanzees. However, cross-sectional comparisons revealed a significant quadratic relationship between age and NLR, with the highest values during mid-life (20-30 years of age) and the lowest values in younger and older individuals. Additionally, males and mother-reared individuals had higher NLR than females and nursery-reared chimpanzees, respectively. Lastly, males and those with higher NLR values died at younger ages. These findings suggest that NLR may be useful as a predictor of longevity in chimpanzees. However, given the complexities of these relationships, more research is needed to determine the utility of NLR as a diagnostic health tool for chimpanzees.


Assuntos
Linfócitos/citologia , Linfócitos/metabolismo , Neutrófilos/citologia , Neutrófilos/metabolismo , Animais , Feminino , Contagem de Linfócitos , Masculino , Pan troglodytes
10.
Molecules ; 25(24)2020 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33322198

RESUMO

Angiotensin-converting enzyme 2 (ACE2) is the cellular receptor for the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that is engendering the severe coronavirus disease 2019 (COVID-19) pandemic. The spike (S) protein receptor-binding domain (RBD) of SARS-CoV-2 binds to the three sub-domains viz. amino acids (aa) 22-42, aa 79-84, and aa 330-393 of ACE2 on human cells to initiate entry. It was reported earlier that the receptor utilization capacity of ACE2 proteins from different species, such as cats, chimpanzees, dogs, and cattle, are different. A comprehensive analysis of ACE2 receptors of nineteen species was carried out in this study, and the findings propose a possible SARS-CoV-2 transmission flow across these nineteen species.


Assuntos
Glicoproteína da Espícula de Coronavírus , /genética , Animais , /metabolismo , Gatos , Bovinos , Cães , Humanos , Pan troglodytes , Domínios Proteicos , /metabolismo , Especificidade da Espécie , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
11.
Science ; 370(6515): 403-404, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33093096
12.
PLoS One ; 15(9): e0238066, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32916689

RESUMO

Oxidative stress (OS) plays a marked role in aging and results from a variety of stressors, making it a powerful measure of health and a way to examine costs associated with life history investments within and across species. However, few urinary OS markers have been examined under field conditions, particularly in primates, and their utility to non-invasively monitor the costs of acute stressors versus the long-term damage associated with aging is poorly understood. In this study, we examined variation in 5 urinary markers of oxidative damage and protection under 5 validation paradigms for 37 wild, chimpanzees living in the Kibale National Park, Uganda. We used 924 urine samples to examine responses to acute immune challenge (respiratory illness or severe wounding), as well as mixed-longitudinal and intra-individual variation with age. DNA damage (8-OHdG) correlated positively with all other markers of damage (F-isoprostanes, MDA-TBARS, and neopterin) but did not correlate with protection (total antioxidant capacity). Within individuals, all markers of damage responded to at least one if not both types of acute infection. While OS is expected to increase with age, this was not generally true in chimpanzees. However, significant changes in oxidative damage were detected within past-prime individuals and those close to death. Our results indicate that OS can be measured using field-collected urine and integrates short- and long-term aspects of health. They further suggest that more data are needed from long-lived, wild animals to illuminate if common age-related increases in inflammation and OS damage are typical or recently aberrant in humans.


Assuntos
Envelhecimento , Biomarcadores/urina , Estresse Oxidativo , 8-Hidroxi-2'-Desoxiguanosina/urina , Animais , Animais Selvagens , Antioxidantes/química , Antioxidantes/metabolismo , Isoprostanos/urina , Pneumopatias/patologia , Pneumopatias/urina , Neopterina/urina , Pan troglodytes , Ferimentos e Lesões/patologia , Ferimentos e Lesões/urina
13.
BMC Evol Biol ; 20(1): 119, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933484

RESUMO

BACKGROUND: Many species are threatened with extinction as their population sizes decrease with changing environments or face novel pathogenic threats. A reduction of genetic diversity at major histocompatibility complex (MHC) genes may have dramatic effects on populations' survival, as these genes play a key role in adaptive immunity. This might be the case for chimpanzees, the MHC genes of which reveal signatures of an ancient selective sweep likely due to a viral epidemic that reduced their population size a few million years ago. To better assess how this past event affected MHC variation in chimpanzees compared to humans, we analysed several indexes of genetic diversity and linkage disequilibrium across seven MHC genes on four cohorts of chimpanzees and we compared them to those estimated at orthologous HLA genes in a large set of human populations. RESULTS: Interestingly, the analyses uncovered similar patterns of both molecular diversity and linkage disequilibrium across the seven MHC genes in chimpanzees and humans. Indeed, in both species the greatest allelic richness and heterozygosity were found at loci A, B, C and DRB1, the greatest nucleotide diversity at loci DRB1, DQA1 and DQB1, and both significant global linkage disequilibrium and the greatest proportions of haplotypes in linkage disequilibrium were observed at pairs DQA1 ~ DQB1, DQA1 ~ DRB1, DQB1 ~ DRB1 and B ~ C. Our results also showed that, despite some differences among loci, the levels of genetic diversity and linkage disequilibrium observed in contemporary chimpanzees were globally similar to those estimated in small isolated human populations, in contrast to significant differences compared to large populations. CONCLUSIONS: We conclude, first, that highly conserved mechanisms shaped the diversity of orthologous MHC genes in chimpanzees and humans. Furthermore, our findings support the hypothesis that an ancient demographic decline affecting the chimpanzee populations - like that ascribed to a viral epidemic - exerted a substantial effect on the molecular diversity of their MHC genes, albeit not more pronounced than that experienced by HLA genes in human populations that underwent rapid genetic drift during humans' peopling history. We thus propose a model where chimpanzees' MHC genes regenerated molecular variation through recombination/gene conversion and/or balancing selection after the selective sweep.


Assuntos
Evolução Molecular , Variação Genética , Antígenos HLA-D/genética , Hominidae/genética , Desequilíbrio de Ligação , Pan troglodytes , Alelos , Animais , Frequência do Gene , Genética Populacional , Haplótipos , Humanos , Pan troglodytes/genética
14.
Nat Commun ; 11(1): 4451, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934202

RESUMO

Large brains and behavioural innovation are positively correlated, species-specific traits, associated with the behavioural flexibility animals need for adapting to seasonal and unpredictable habitats. Similar ecological challenges would have been important drivers throughout human evolution. However, studies examining the influence of environmental variability on within-species behavioural diversity are lacking despite the critical assumption that population diversification precedes genetic divergence and speciation. Here, using a dataset of 144 wild chimpanzee (Pan troglodytes) communities, we show that chimpanzees exhibit greater behavioural diversity in environments with more variability - in both recent and historical timescales. Notably, distance from Pleistocene forest refugia is associated with the presence of a larger number of behavioural traits, including both tool and non-tool use behaviours. Since more than half of the behaviours investigated are also likely to be cultural, we suggest that environmental variability was a critical evolutionary force promoting the behavioural, as well as cultural diversification of great apes.


Assuntos
Comportamento Animal , Pan troglodytes/psicologia , Animais , Ecossistema , Meio Ambiente , Feminino , Florestas , Masculino , Pan troglodytes/fisiologia , Comportamento de Utilização de Ferramentas
15.
Proc Biol Sci ; 287(1934): 20201320, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32900313

RESUMO

Once considered a hallmark of human uniqueness, brain asymmetry has emerged as a feature shared with several other species, including chimpanzees, one of our closest living relatives. Most notable has been the discovery of asymmetries in homologues of cortical language areas in apes, particularly in the planum temporale (PT), considered a central node of the human language network. Several lines of evidence indicate a role for genetic mechanisms in the emergence of PT asymmetry; however, the genetic determinants of cerebral asymmetries have remained elusive. Studies in humans suggest that there is heritability of brain asymmetries of the PT, but this has not been explored to any extent in chimpanzees. Furthermore, the potential influence of non-genetic factors has raised questions about the reproducibility of earlier observations of PT asymmetry reported in chimpanzees. As such, the present study was aimed at examining both the heritability of phenotypic asymmetries in PT morphology, as well as their reproducibility. Using magnetic resonance imaging, we evaluated morphological asymmetries of PT surface area (mm2) and mean depth (mm) in captive chimpanzees (n = 291) derived from two genetically isolated populations. Our results confirm that chimpanzees exhibit a significant population-level leftward asymmetry for PT surface area, as well as significant heritability in the surface area and mean depth of the PT. These results conclusively demonstrate the existence of a leftward bias in PT asymmetry in chimpanzees and suggest that genetic mechanisms play a key role in the emergence of anatomical asymmetry in this region.


Assuntos
Pan troglodytes/fisiologia , Lobo Temporal/anatomia & histologia , Animais , Mapeamento Encefálico , Feminino , Imagem por Ressonância Magnética , Masculino , Reprodutibilidade dos Testes
16.
PLoS Pathog ; 16(9): e1008812, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32913367

RESUMO

The APOBEC3 deaminases are potent inhibitors of virus replication and barriers to cross-species transmission. For simian immunodeficiency virus (SIV) to transmit to a new primate host, as happened multiple times to seed the ongoing HIV-1 epidemic, the viral infectivity factor (Vif) must be capable of neutralizing the APOBEC3 enzymes of the new host. Although much is known about current interactions of HIV-1 Vif and human APOBEC3s, the evolutionary changes in SIV Vif required for transmission from chimpanzees to gorillas and ultimately to humans are poorly understood. Here, we demonstrate that gorilla APOBEC3G is a factor with the potential to hamper SIV transmission from chimpanzees to gorillas. Gain-of-function experiments using SIVcpzPtt Vif revealed that this barrier could be overcome by a single Vif acidic amino acid substitution (M16E). Moreover, degradation of gorilla APOBEC3F is induced by Vif through a mechanism that is distinct from that of human APOBEC3F. Thus, our findings identify virus adaptations in gorillas that preceded and may have facilitated transmission to humans.


Assuntos
Desaminase APOBEC-3G/metabolismo , Evolução Molecular , Produtos do Gene vif/metabolismo , Interações Hospedeiro-Patógeno , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Vírus da Imunodeficiência Símia/isolamento & purificação , Replicação Viral , Desaminase APOBEC-3G/química , Desaminase APOBEC-3G/genética , Sequência de Aminoácidos , Animais , Produtos do Gene vif/química , Produtos do Gene vif/genética , Gorilla gorilla , Humanos , Pan troglodytes , Filogenia , Conformação Proteica , Homologia de Sequência , Síndrome de Imunodeficiência Adquirida dos Símios/virologia
17.
PLoS Pathog ; 16(8): e1008793, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866189

RESUMO

Transmission to chimpanzees of a precore hepatitis B virus (HBV) mutant implicated in acute liver failure (ALF) in humans did not cause ALF nor the classic form of acute hepatitis B (AHB) seen upon infection with the wild-type HBV strain, but rather a severe AHB with distinct disease features. Here, we investigated the viral and host immunity factors responsible for the unusual severity of AHB associated with the precore HBV mutant in chimpanzees. Archived serial serum and liver specimens from two chimpanzees inoculated with a precore HBV mutant implicated in ALF and two chimpanzees inoculated with wild-type HBV were studied. We used phage-display library and next-generation sequencing (NGS) technologies to characterize the liver antibody response. The results obtained in severe AHB were compared with those in classic AHB and HBV-associated ALF in humans. Severe AHB was characterized by: (i) the highest alanine aminotransferase (ALT) peaks ever seen in HBV transmission studies with a significantly shorter incubation period, compared to classic AHB; (ii) earlier HBsAg clearance and anti-HBs seroconversion with transient or undetectable hepatitis B e antigen (HBeAg); (iii) limited inflammatory reaction relative to hepatocellular damage at the ALT peak with B-cell infiltration, albeit less extensive than in ALF; (iv) detection of intrahepatic germline antibodies against hepatitis B core antigen (HBcAg) by phage-display libraries in the earliest disease phase, as seen in ALF; (v) lack of intrahepatic IgM anti-HBcAg Fab, as seen in classic AHB, but at variance with ALF; and (vi) higher proportion of antibodies in germline configuration detected by NGS in the intrahepatic antibody repertoire compared to classic AHB, but lower than in ALF. This study identifies distinct outcome-specific features associated with severe AHB caused by a precore HBV mutant in chimpanzees, which bear closer resemblance to HBV ALF than to classic AHB. Our data suggest that precore HBV mutants carry an inherently higher pathogenicity that, in addition to specific host factors, may play a critical role in determining the severity of acute HBV disease.


Assuntos
Anticorpos Anti-Hepatite B/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B/metabolismo , Imunoglobulina M/metabolismo , Falência Hepática Aguda/metabolismo , Animais , Modelos Animais de Doenças , Hepatite B/patologia , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Humanos , Falência Hepática Aguda/patologia , Pan troglodytes
18.
PLoS One ; 15(7): e0235610, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32663207

RESUMO

The greying of human head hair is arguably the most salient marker of human aging. In wild mammal populations, greying can change with life history or environmental factors (e.g., sexual maturity in silverback gorillas). Yet, whether humans are unique in our pattern of age-related hair depigmentation is unclear. We examined the relationship between pigmentation loss in facial hair (greying) to age, population, and sex in wild and captive chimpanzees (Pan troglodytes). Digital facial photographs representing three chimpanzee populations (N = 145; ages 1-60 years) were scored for hair greying on a scale of one [~100% pigmented] to six [~0% pigmented]. Our data suggest that chimpanzee head and facial hair generally greys with age prior to mid-life (~30 years old), but afterwards, greying ceases to increase incrementally. Our results highlight that chimpanzee pigmentation likely exhibits substantial variation between populations, and that both 'grey' and pigmented phenotypes exist across various age classes. Thus, chimpanzee facial hair greying is unlikely a progressive indicator of age beyond mid-life, and thus facial greying in chimpanzees seems different from the pattern observed in humans. Whether this reflects neutral differences in senescence, or potential differences in selection pressures (e.g. related to conspecific communication), is unclear and worthy of more detailed examination across populations and taxa.


Assuntos
Envelhecimento/metabolismo , Cor de Cabelo , Pan troglodytes , Animais , Biomarcadores/metabolismo , Feminino , Masculino
19.
PLoS Negl Trop Dis ; 14(7): e0008459, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32667913

RESUMO

Rabies, caused by RNA viruses in the Genus Lyssavirus, is the most fatal of all infectious diseases. This neglected zoonosis remains a major public health problem in developing countries, causing the death of an estimated 25,000-159,000 people each year, with more than half of them in children. The high incidence of human rabies in spite of effective vaccines is mainly linked to the lack of compliance with the complicated administration schedule, inadequacies of the community public health system for local administration by the parenteral route and the overall costs of the vaccine. The goal of our work was the development of a simple, affordable and effective vaccine strategy to prevent human rabies virus infection. This next generation vaccine is based on a replication-defective chimpanzee adenovirus vector belonging to group C, ChAd155-RG, which encodes the rabies glycoprotein (G). We demonstrate here that a single dose of this vaccine induces protective efficacy in a murine model of rabies challenge and elicits strong and durable neutralizing antibody responses in vaccinated non-human primates. Importantly, we demonstrate that one dose of a commercial rabies vaccine effectively boosts the neutralizing antibody responses induced by ChAd155-RG in vaccinated monkeys, showing the compatibility of the novel vectored vaccine with the current post-exposure prophylaxis in the event of rabies virus exposure. Finally, we demonstrate that antibodies induced by ChAd155-RG can also neutralize European bat lyssaviruses 1 and 2 (EBLV-1 and EBLV-2) found in bat reservoirs.


Assuntos
Adenovirus dos Símios/genética , Vacinas Antirrábicas/imunologia , Raiva/prevenção & controle , Animais , Antígenos Virais , Feminino , Vetores Genéticos/genética , Humanos , Macaca fascicularis , Camundongos , Pan troglodytes/virologia , Profilaxia Pós-Exposição , Coelhos , Vírus da Raiva/genética , Vírus da Raiva/imunologia , Sorogrupo , Vacinação , Vacinas Sintéticas/imunologia , Zoonoses
20.
Biol Lett ; 16(7): 20200201, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32673550

RESUMO

Group-living animals can develop social bonds. Social bonds can be considered a type of social relationship characterized by frequent and consistent affiliative (non-reproductive) interactions. Social bonds with conspecifics bring many advantages, also in terms of direct fitness. A characteristic of social bonds is that they need time to develop. Several studies on humans have emphasized the fact that sharing experiences can affect the strength of social bonds. A similar trend can be spotted in non-human species. For example, a recent experiment showed that if chimpanzees watched a video together with a conspecific, they spent more time in proximity compared to conspecifics with whom they did not actively watch a video. Another experiment on fish showed that individuals who experienced a situation of high predation risk together, showed preference for each other compared to those who did not. As the link between shared experiences and social bonds is not explicitly recognized in non-human animals, the main goal of this work is to propose the exploration of this novel research path. This exploration would contribute to shed light on the evolutionary mechanisms of social bond (or friendship) development and maintenance between individuals in different vertebrate species, from fish to non-human primates.


Assuntos
Pan troglodytes , Primatas , Animais , Humanos , Motivação , Comportamento Predatório , Reprodução , Comportamento Social
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