scholarly journals Localization of infection in neonatal rhesus macaques after oral viral challenge

2021 ◽  
Author(s):  
Thomas J. Hope ◽  
Roslyn A. Taylor ◽  
Michael D. McRaven ◽  
Ann M. Carias ◽  
Meegan R. Anderson ◽  
...  

While vertical transmission of human immunodeficiency virus (HIV) can occur  in utero  and during delivery and through breastfeeding. We utilized Positron Emission Tomography (PET) imaging coupled with fluorescent microscopy of  64 Cu-labeled photoactivatable-GFP-HIV (PA-GFP-BaL) to determine how HIV virions distribute and localize in neonatal rhesus macaques two and four hours after oral viral challenge. Our results show that by four hours after oral viral exposure, HIV virions localize to and penetrate the rectal mucosa. We also used a dual viral challenge with a non-replicative viral vector and a replication competent SHIV-1157ipd3N4 to examine viral transduction and dissemination at 96 hours. Our data show that while SHIV-1157ipd3N4 infection can be found in the oral cavity and upper gastrointestinal (GI) tract, the small and large intestine contained the largest number of infected cells. Moreover, we found that T cells were the biggest population of infected immune cells. Thus, thanks to these novel technologies, we are able to visualize and delineate of viral distribution and infection throughout the entire neonatal GI tract during acute viral infection.

2021 ◽  
Vol 17 (11) ◽  
pp. e1009855
Author(s):  
Roslyn A. Taylor ◽  
Michael D. McRaven ◽  
Ann M. Carias ◽  
Meegan R. Anderson ◽  
Edgar Matias ◽  
...  

Vertical transmission of human immunodeficiency virus (HIV) can occur in utero, during delivery, and through breastfeeding. We utilized Positron Emission Tomography (PET) imaging coupled with fluorescent microscopy of 64Cu-labeled photoactivatable-GFP-HIV (PA-GFP-BaL) to determine how HIV virions distribute and localize in neonatal rhesus macaques two and four hours after oral viral challenge. Our results show that by four hours after oral viral exposure, HIV virions localize to and penetrate the rectal mucosa. We also used a dual viral challenge with a non-replicative viral vector and a replication competent SHIV-1157ipd3N4 to examine viral transduction and dissemination at 96 hours. Our data show that while SHIV-1157ipd3N4 infection can be found in the oral cavity and upper gastrointestinal (GI) tract, the small and large intestine contained the largest number of infected cells. Moreover, we found that T cells were the biggest population of infected immune cells. Thus, thanks to these novel technologies, we are able to visualize and delineate of viral distribution and infection throughout the entire neonatal GI tract during acute viral infection.


2020 ◽  
Author(s):  
Roslyn A. Taylor ◽  
Sixia Xiao ◽  
Ann M. Carias ◽  
Michael D. McRaven ◽  
Divya N. Thakkar ◽  
...  

AbstractHIV vaccines have not been successful in clinical trials. Dimeric IgA (dIgA) is the most abundant antibody class in mucosal tissues, making dIgA a prime candidate for potential HIV vaccines. We coupled Positron Emission Tomography (PET) imaging and fluorescent microscopy of 64Cu-labeled, photoactivatable-GFP HIV (PA-GFP-BaL) and fluorescently labeled dIgA to determine how dIgA antibodies influence virus interaction with mucosal barriers and viral penetration in colorectal tissue. Our results show that HIV virions rapidly disseminate throughout the colon two hours after exposure. The presence of dIgA resulted in an increase in virions and penetration depth in the transverse colon. Moreover, virions were found in the mesenteric lymph nodes two hours after viral exposure, and the presence of dIgA led to an increase in virions in mesenteric lymph nodes. Taken together, these technologies enable in vivo and in situ visualization of antibody-virus interactions and detailed investigations of early events in HIV infection.


2021 ◽  
Vol 17 (6) ◽  
pp. e1009632
Author(s):  
Roslyn A. Taylor ◽  
Sixia Xiao ◽  
Ann M. Carias ◽  
Michael D. McRaven ◽  
Divya N. Thakkar ◽  
...  

Human immunodeficiency virus (HIV) vaccines have not been successful in clinical trials. Dimeric IgA (dIgA) in the form of secretory IgA is the most abundant antibody class in mucosal tissues, making dIgA a prime candidate for potential HIV vaccines. We coupled Positron Emission Tomography (PET) imaging and fluorescent microscopy of 64Cu-labeled, photoactivatable-GFP HIV (PA-GFP-BaL) and fluorescently labeled dIgA to determine how dIgA antibodies influence virus interaction with mucosal barriers and viral penetration in colorectal tissue. Our results show that HIV virions rapidly disseminate throughout the colon two hours after exposure. The presence of dIgA resulted in an increase in virions and penetration depth in the transverse colon. Moreover, virions were found in the mesenteric lymph nodes two hours after viral exposure, and the presence of dIgA led to an increase in virions in mesenteric lymph nodes. Taken together, these technologies enable in vivo and in situ visualization of antibody-virus interactions and detailed investigations of early events in HIV infection.


2009 ◽  
Vol 90 (3) ◽  
pp. 614-625 ◽  
Author(s):  
Joanne L. Tan ◽  
Norihito Ueda ◽  
Andrew A. Mercer ◽  
Stephen B. Fleming

Orf virus (ORFV) is the type species of the genus Parapoxvirus, but little is known about the structure or morphogenesis of the virus. In contrast, the structure and morphogenesis of vaccinia virus (VACV) has been extensively studied. VACV has two main infectious forms, mature virion (MV) and extracellular virion (EV). The MV is wrapped by two additional membranes derived from the trans-Golgi to produce a wrapped virion (WV), the outermost of which is lost by cellular membrane fusion during viral egress to form the EV. Genome sequencing of ORFV has revealed that it has homologues of almost all of the VACV structural genes. Notable exceptions are A36R, K2L, A56R and B5R, which are associated with WV and EV envelopes. This study investigated the morphogenesis and structure of ORFV by fusing FLAG peptide to the structural proteins 10 kDa, F1L and ORF-110 to form recombinant viruses. 10 kDa and F1L are homologues of VACV A27L and H3L MV membrane proteins, whilst ORF-110 is homologous to VACV A34R, an EV membrane protein. Immunogold labelling of FLAG proteins on virus particles isolated from lysed cells showed that FLAG–F1L and FLAG–10 kDa were displayed on the surface of infectious particles, whereas ORF-110–FLAG could not be detected. Western blot analysis of solubilized recombinant ORF-110–FLAG particles revealed that ORF-110–FLAG was abundant and undergoes post-translational modification indicative of endoplasmic reticulum trafficking. Fluorescent microscopy confirmed the prediction that ORF-110–FLAG localized to the Golgi in virus-infected cells. Finally, immunogold labelling of EVs showed that ORF-110–FLAG became exposed on the surface of EV-like particles as a result of egress from the cell.


Blood ◽  
2020 ◽  
Vol 136 (23) ◽  
pp. 2667-2678
Author(s):  
So Gun Hong ◽  
Noriko Sato ◽  
Fanny Legrand ◽  
Manasi Gadkari ◽  
Michelle Makiya ◽  
...  

Abstract Glucocorticoids are considered first-line therapy in a variety of eosinophilic disorders. They lead to a transient, profound decrease in circulating human eosinophils within hours of administration. The phenomenon of glucocorticoid-induced eosinopenia has been the basis for the use of glucocorticoids in eosinophilic disorders, and it has intrigued clinicians for 7 decades, yet its mechanism remains unexplained. To investigate, we first studied the response of circulating eosinophils to in vivo glucocorticoid administration in 3 species and found that the response in rhesus macaques, but not in mice, closely resembled that in humans. We then developed an isolation technique to purify rhesus macaque eosinophils from peripheral blood and performed live tracking of zirconium-89-oxine–labeled eosinophils by serial positron emission tomography/computed tomography imaging, before and after administration of glucocorticoids. Glucocorticoids induced rapid bone marrow homing of eosinophils. The kinetics of glucocorticoid-induced eosinopenia and bone marrow migration were consistent with those of the induction of the glucocorticoid-responsive chemokine receptor CXCR4, and selective blockade of CXCR4 reduced or eliminated the early glucocorticoid-induced reduction in blood eosinophils. Our results indicate that glucocorticoid-induced eosinopenia results from CXCR4-dependent migration of eosinophils to the bone marrow. These findings provide insight into the mechanism of action of glucocorticoids in eosinophilic disorders, with implications for the study of glucocorticoid resistance and the development of more targeted therapies. The human study was registered at ClinicalTrials.gov as #NCT02798523.


2020 ◽  
Vol 29 (14) ◽  
pp. 805-811
Author(s):  
Pineshwari Naeck-Boolauky ◽  
Jitka Adio ◽  
Jennie Burch

The gastrointestinal (GI) tract has a number of functions—ingestion, digestion, absorption and elimination. When the GI tract is working normally, it is efficient. However, this can change when disease, such as inflammatory bowel disease (IBD) occurs. IBD is a long-term relapsing and remitting autoimmune disease; it incorporates ulcerative colitis (UC). In UC, part or all the mucosa lining the rectum and colon becomes inflamed and ulcerated. UC that affects the rectum only is called proctitis. Effective treatment is essential. It is better to target the rectal mucosa directly in proctitis, using topical rectal medications in enemas or suppositories, as these have fewer side-effects and resolve symptoms more quickly than systemic drugs. However, patients may not feel clear about aspects of their IBD care and can find it difficult to initiate and comply with treatment and maintenance regimens. Nurses need to educate and support them to achieve optimal therapeutic outcomes in both the immediate and long terms.


Glycobiology ◽  
2018 ◽  
Vol 29 (2) ◽  
pp. 151-162 ◽  
Author(s):  
Fang-Yen Li ◽  
I-Chun Weng ◽  
Chun-Hung Lin ◽  
Mou-Chieh Kao ◽  
Ming-Shiang Wu ◽  
...  

Abstract Galectin-8, a beta-galactoside-binding lectin, is upregulated in the gastric tissues of rhesus macaques infected with Helicobacter pylori. In this study, we found that H. pylori infection triggers intracellular galectin-8 aggregation in human-derived AGS gastric epithelial cells, and that these aggregates colocalize with lysosomes. Notably, this aggregation is markedly reduced following the attenuation of host O-glycan processing. This indicates that H. pylori infection induces lysosomal damage, which in turn results in the accumulation of cytosolic galectin-8 around damaged lysosomes through the recognition of exposed vacuolar host O-glycans. H. pylori-induced galectin-8 aggregates also colocalize with autophagosomes, and galectin-8 ablation reduces the activation of autophagy by H. pylori. This suggests that galectin-8 aggregates may enhance autophagy activity in infected cells. We also observed that both autophagy and NDP52, an autophagy adapter, contribute to the augmentation of galectin-8 aggregation by H. pylori. Additionally, vacuolating cytotoxin A, a secreted H. pylori cytotoxin, may contribute to the increased galectin-8 aggregation and elevated autophagy response in infected cells. Collectively, these results suggest that H. pylori promotes intracellular galectin-8 aggregation, and that galectin-8 aggregation and autophagy may reciprocally regulate each other during infection.


Nature ◽  
2020 ◽  
Vol 577 (7788) ◽  
pp. 95-102 ◽  
Author(s):  
Patricia A. Darrah ◽  
Joseph J. Zeppa ◽  
Pauline Maiello ◽  
Joshua A. Hackney ◽  
Marc H. Wadsworth ◽  
...  

AbstractMycobacterium tuberculosis (Mtb) is the leading cause of death from infection worldwide1. The only available vaccine, BCG (Bacillus Calmette–Guérin), is given intradermally and has variable efficacy against pulmonary tuberculosis, the major cause of mortality and disease transmission1,2. Here we show that intravenous administration of BCG profoundly alters the protective outcome of Mtb challenge in non-human primates (Macaca mulatta). Compared with intradermal or aerosol delivery, intravenous immunization induced substantially more antigen-responsive CD4 and CD8 T cell responses in blood, spleen, bronchoalveolar lavage and lung lymph nodes. Moreover, intravenous immunization induced a high frequency of antigen-responsive T cells across all lung parenchymal tissues. Six months after BCG vaccination, macaques were challenged with virulent Mtb. Notably, nine out of ten macaques that received intravenous BCG vaccination were highly protected, with six macaques showing no detectable levels of infection, as determined by positron emission tomography–computed tomography imaging, mycobacterial growth, pathology and granuloma formation. The finding that intravenous BCG prevents or substantially limits Mtb infection in highly susceptible rhesus macaques has important implications for vaccine delivery and clinical development, and provides a model for defining immune correlates and mechanisms of vaccine-elicited protection against tuberculosis.


2016 ◽  
Vol 90 (13) ◽  
pp. 6127-6139 ◽  
Author(s):  
Benjamin von Bredow ◽  
Juan F. Arias ◽  
Lisa N. Heyer ◽  
Brian Moldt ◽  
Khoa Le ◽  
...  

ABSTRACTAlthough antibodies to the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein have been studied extensively for their ability to block viral infectivity, little data are currently available on nonneutralizing functions of these antibodies, such as their ability to eliminate virus-infected cells by antibody-dependent cell-mediated cytotoxicity (ADCC). HIV-1 Env-specific antibodies of diverse specificities, including potent broadly neutralizing and nonneutralizing antibodies, were therefore tested for ADCC against cells infected with a lab-adapted HIV-1 isolate (HIV-1NL4-3), a primary HIV-1 isolate (HIV-1JR-FL), and a simian-human immunodeficiency virus (SHIV) adapted for pathogenic infection of rhesus macaques (SHIVAD8-EO). In accordance with the sensitivity of these viruses to neutralization, HIV-1NL4-3-infected cells were considerably more sensitive to ADCC, both in terms of the number of antibodies and magnitude of responses, than cells infected with HIV-1JR-FLor SHIVAD8-EO. ADCC activity generally correlated with antibody binding to Env on the surfaces of virus-infected cells and with viral neutralization; however, neutralization was not always predictive of ADCC, as instances of ADCC in the absence of detectable neutralization, and vice versa, were observed. These results reveal incomplete overlap in the specificities of antibodies that mediate these antiviral activities and provide insights into the relationship between ADCC and neutralization important for the development of antibody-based vaccines and therapies for combating HIV-1 infection.IMPORTANCEThis study provides fundamental insights into the relationship between antibody-dependent cell-mediated cytotoxicity (ADCC) and virus neutralization that may help to guide the development of antibody-based vaccines and immunotherapies for the prevention and treatment of HIV-1 infection.


2002 ◽  
Vol 76 (2) ◽  
pp. 688-696 ◽  
Author(s):  
Christiane Stahl-Hennig ◽  
Ralph M. Steinman ◽  
Peter Ten Haaft ◽  
Klaus Überla ◽  
Nicole Stolte ◽  
...  

ABSTRACT Deletion of the nef gene from simian immunodeficiency virus (SIV) strain SIVmac239 yields a virus that undergoes attenuated growth in rhesus macaques and offers substantial protection against a subsequent challenge with some SIV wild-type viruses. We used a recently described model to identify sites in which the SIVΔnef vaccine strain replicates and elicits immunity in vivo. A high dose of SIVΔnef was applied to the palatine and lingual tonsils, where it replicated vigorously in this portal of entry at 7 days. Within 2 weeks, the virus had spread and was replicating actively in axillary lymph nodes, primarily in extrafollicular T-cell-rich regions but also in germinal centers. At this time, large numbers of perforin-positive cells, both CD8+ T cells and CD3-negative presumptive natural killer cells, were found in the tonsil and axillary lymph nodes. The number of infected cells and perforin-positive cells then fell. When autopsy studies were carried out at 26 weeks, only 1 to 3 cells hybridized for viral RNA per section of lymphoid tissue. Nevertheless, infected cells were detected chronically in most lymphoid organs, where the titers of infectious virus could exceed by a log or more the titers in blood. Immunocytochemical labeling at the early active stages of infection showed that cells expressing SIVΔnef RNA were CD4+ T lymphocytes. A majority of infected cells were not in the active cell cycle, since 60 to 70% of the RNA-positive cells in tissue sections lacked the Ki-67 cell cycle antigen, and both Ki-67-positive and -negative cells had similar grain counts for viral RNA. Macrophages and dendritic cells, identified with a panel of monoclonal antibodies to these cells, were rarely infected. We conclude that the attenuated growth and protection observed with the SIVΔnef vaccine strain does not require that the virus shift its characteristic site of replication, the CD4+ T lymphocyte. In fact, this immunodeficiency virus can replicate actively in CD4+ T cells prior to being contained by the host, at least in part by a strong killer cell response that is generated acutely in the infected lymph nodes.


Sign in / Sign up

Export Citation Format

Share Document