Interactions between vaccinia virus and sensitized macrophages in vitro

The action of peritoneal exudate cells (PEC) from normal and vaccinia virus infected mice on infectious vaccinia virus particles was investigatedin vitro. PEC from immune mice showed a significantly higher infectivity titre reduction (virus clearance, VC) than normal cells. This effect could be clearly attributed to the macrophage. Vaccinia virus multiplied in PEC from normal animals while there was no virus propagation in cells from immunized mice. The release of adsorbed or engulfed virus was reduced significantly in PEC from immunized animals. Anti-vaccinia-antibodies seem to activate normal macrophages to increased virus clearance. This stimulating effect was demonstrable only in the IgG fraction of the antiserum. The activity of macrophages from mice injected three times over a period of 14 days with vaccinia virus could be entirely blocked with anti-mouse-IgG, while PEC from mice injected one time six days previously were not inhibited

Acute Infection and Subsequent Subclinical Reactivation of Herpes Simplex Virus 2 after Vaginal Inoculation of Rhesus Macaques.

Herpes simplex virus 2 (HSV-2) is a common sexually transmitted infection with a highly variable clinical course. Many infections quickly become subclinical, with episodes of spontaneous virus reactivation. To study host-HSV-2 interactions, an animal model of subclinical HSV-2 infection is needed. In an effort to develop a relevant model, rhesus macaques (RM) were inoculated intravaginally with two or three HSV-2 strains (186, 333, and/or G) at a total dose of 1 × 107 PFU of HSV-2 per animal. Infectious HSV-2 and HSV-2 DNA were consistently shed in vaginal swabs for the first 7 to 14 days after each inoculation. Proteins associated with wound healing, innate immunity, and inflammation were significantly increased in cervical secretions immediately after HSV-2 inoculation. There was histologic evidence of acute herpesvirus pathology, including acantholysis in the squamous epithelium and ballooning degeneration of and intranuclear inclusion bodies in epithelial cells, with HSV antigen in mucosal epithelial cells and keratinocytes. Further, an intense inflammatory infiltrate was found in the cervix and vulva. Evidence of latent infection and reactivation was demonstrated by the detection of spontaneous HSV-2 shedding post-acute inoculation (102 to 103 DNA copies/swab) in 80% of RM. Further, HSV-2 DNA was detected in ganglia in most necropsied animals. HSV-2-specifc T-cell responses were detected in all animals, although antibodies to HSV-2 were detected in only 30% of the animals. Thus, HSV-2 infection of RM recapitulates many of the key features of subclinical HSV-2 infection in women but seems to be more limited, as virus shedding was undetectable more than 40 days after the last virus inoculation.IMPORTANCE Herpes simplex virus 2 (HSV-2) infects nearly 500 million persons globally, with an estimated 21 million incident cases each year, making it one of the most common sexually transmitted infections (STIs). HSV-2 is associated with increased human immunodeficiency virus type 1 (HIV-1) acquisition, and this risk does not decline with the use of antiherpes drugs. As initial acquisition of both HIV and HSV-2 infections is subclinical, study of the initial molecular interactions of the two agents requires an animal model. We found that HSV-2 can infect RM after vaginal inoculation, establish latency in the nervous system, and spontaneously reactivate; these features mimic some of the key features of HSV-2 infection in women. RM may provide an animal model to develop strategies to prevent HSV-2 acquisition and reactivation

Zika virus preferentially replicates in the female reproductive tract after vaginal inoculation of rhesus macaques.

Zika virus (ZIKV) is a mosquito-transmitted virus that can cause severe defects in an infected fetus. ZIKV is also transmitted by sexual contact, although the relative importance of sexual transmission is unclear. To better understand the role of sexual transmission in ZIKV pathogenesis, a nonhuman primate (NHP) model of vaginal transmission was developed. ZIKV was readily transmitted to mature cycling female rhesus macaque (RM) by vaginal inoculation with 104-106 plaque-forming units (PFU). However, there was variability in susceptibility between the individual RM with 1->8 vaginal inoculations required to establish infection. After treatment with Depoprovera, a widely used contraceptive progestin, two RM that initially resisted 8 vaginal ZIKV inoculations became infected after one ZIKV inoculation. Thus, Depoprovera seemed to enhance susceptibility to vaginal ZIKV transmission. Unexpectedly, the kinetics of virus replication and dissemination after intravaginal ZIKV inoculation were markedly different from RM infected with ZIKV by subcutaneous (SQ) virus inoculation. Several groups have reported that after SQ ZIKV inoculation vRNA is rapidly detected in blood plasma with vRNA less common in urine and saliva and only rarely detected in female reproductive tract (FRT) secretions. In contrast, in vaginally inoculated RM, plasma vRNA is delayed for several days and ZIKV replication in, and vRNA shedding from, the FRT was found in all 6 animals. Further, after intravaginal transmission ZIKV RNA shedding from FRT secretions was detected before or simultaneously with plasma vRNA, and persisted for at least as long. Thus, ZIKV replication in the FRT was independent of, and often preceded virus replication in the tissues contributing to plasma vRNA. These results support the conclusion that ZIKV preferentially replicates in the FRT after vaginal transmission, but not after SQ transmission, and raise the possibility that there is enhanced fetal infection and pathology after vaginal ZIKV transmission compared to a mosquito transmitted ZIKV

Implementation and Validation of the Roche Light Cycler 480 96-Well Plate Platform as a Real-Time PCR Assay for the Quantitative Detection of Cytomegalovirus (CMV) in Clinical Specimens Using the Luminex MultiCode ASRs System.

Allogenic stem-cell therapies benefit patients in the treatment of multiple diseases; however, the side effects of stem-cell therapies (SCT) derived from the concomitant use of immune suppression agents often include triggering infection diseases. Thus, analysis is required to improve the detection of pathogen infections in SCT. We develop a polymerase chain reaction (PCR)-based methodology for the qualitative real-time DNA detection of cytomegalovirus (CMV), with reference to herpes simplex virus types 1 (HSVI), Epstein-Barr virus (EBV), and varicella-zoster virus (VZV) in blood, urine, solid tissues, and cerebrospinal fluid. This real-time PCR of 96-well plate format provides a rapid framework as required by the Food and Drug Administration (FDA) for clinical settings, including the processing of specimens, reagent handling, special safety precautions, quality control criteria and analytical accuracy, precisely reportable range (analyst measurement range), reference range, limit of detection (LOD), analytical specificity established by interference study, and analyte stability. Specifically, we determined the reportable range (analyst measurement range) with the following criteria: CMV copies ≥200 copies/mL; report copy/mL value; CMV copies ≤199 copies/mL; report detected but below quantitative range; CMV copies = 0 with report <200 copies/mL. That is, with reference range, copy numbers (CN) per milliliter (mL) of the LOD were determined by standard curves that correlated Ct value and calibrated standard DNA panels. The three repeats determined that the measuring range was 1E2~1E6 copies/mL. The standard curves show the slopes were within the range -2.99 to -3.65 with R2 ≥ 0.98. High copy (HC) controls were within 0.17-0.18 log differences of DNA copy numbers; (2) low copy (LC) controls were within 0.17-0.18 log differences; (3) LOD was within 0.14-0.15 log differences. As such, we set up a fast, simple, inexpensive, sensitive, and reliable molecular approach for the qualitative detection of CMV pathogens. Conclusion: This real-time PCR of the 96-well plate format provides a rapid framework as required by the FDA for clinical settings

A case of atypical disseminated herpes simplex virus 1 with hepatitis in a liver transplant recipient: the need for dermatologic evaluation

Disseminated herpes simplex virus (HSV) is mainly seen in immunocompromised individuals. Atypical lesions can be present in both primary infection and reactivation disease. Compared with the general population, inmunocompromised hosts are at greater risk of increased persistency and severity of clinical manifestations, including severe systemic involvement such as esophagitis, meningitis, and hepatitis. Herein, we report the case of a liver transplant recipient with atypical disseminated herpes simplex virus-1 complicated by HSV-related hepatitis. Dermatological consultation and histological assessment were crucial for a correct diagnosis and treatment

Highly Efficient Gene Expression in B Lymphocytes Mediating by Lentivirus Vector

Gene transduction and expression efficiencies among several type cell lines were compared by using vesicular stomatitis virus-glycoprotein (VSV-G) pseudotyped human immunodeficiency virus type-1 (HIV-1) based lentivirus vector. Large discrepancies of the efficiencies were shown among them. B lymphocytes showed high susceptibility of gene transduction and expression, while other cell lines marked lower potential. Variable gene transduction strategies have been assessed to apply immunological therapies. This study showed that B lymphocytes had facilities enough to support the gene transduction and expression by lentivirus vector. Our result suggested that the lentivirus vector would be a powerful tool to express exogenous genes in B lymphocytes

Syndromic and Point-of-Care Molecular Testing

This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic

Infections in recipients of liver homografts.

Seventeen patients received liver homografts between 1963 and May, 1968. The eight treated before July, 1967, died within 34 days; seven had progressive infections with gram-negative bacilli, Candida albicans and cytomegalovirus. The infections were similar to but more fulminating than those after renal homotransplantation. In nine later cases, there was more discriminating donor selection, improved immunosuppression, and better organ preservation. In the first five of these nine patients, all infants, lobar hepatic gangrene apparently secondary to delayed right hepatic arterial thrombosis developed. Two died within a few days, two and three and a half months after transplantation. The three who did not die immediately subsequently had multiple bacteremias, fungemias and cytomegalovirus pulmonary infections. One of these children is alive twelve months after transplantation; the others died after four and a half and six months. In contrast, the last four patients, in whom septic liver infarctions were avoided, have been free of serious infections for two to five and a half months

Single-domain antibodies and their formatting to combat viral infections

Since their discovery in the 1990s, single-domain antibodies (VHHs), also known as NanobodiesA (R), have changed the landscape of affinity reagents. The outstanding solubility, stability, and specificity of VHHs, as well as their small size, ease of production and formatting flexibility favor VHHs over conventional antibody formats for many applications. The exceptional ease by which it is possible to fuse VHHs with different molecular modules has been particularly explored in the context of viral infections. In this review, we focus on VHH formats that have been developed to combat viruses including influenza viruses, human immunodeficiency virus-1 (HIV-1), and human respiratory syncytial virus (RSV). Such formats may significantly increase the affinity, half-life, breadth of protection of an antiviral VHH and reduce the risk of viral escape. In addition, VHHs can be equipped with effector functions, for example to guide components of the immune system with high precision to sites of viral infection

Alveolar Macrophages Isolated Directly From Human Cytomegalovirus (HCMV)-Seropositive Individuals Are Sites of HCMV Reactivation In Vivo.

Human cytomegalovirus (HCMV) causes significant morbidity in the immunocompromised host. Following primary infection, the virus establishes latent infection in progenitor cells of the myeloid lineage. These cells exhibit limited viral gene transcription and no evidence of de novo virion production. It is well recognized that differentiation of latently infected myeloid progenitor cells to dendritic or macrophage-like cells permits viral reactivation in vitro. This has been used to support the concept that viral reactivation in HCMV carriers routinely occurs from such terminally differentiated myeloid cells in vivo. However, to date this has not been shown for in vivo-differentiated macrophages. This study is the first to demonstrate that alveolar macrophages from HCMV carriers express immediate early lytic genes and produce infectious virus. This supports the view, until now based on in vitro data, that terminally differentiated myeloid cells in vivo are sites of HCMV reactivation and potential centers of viral dissemination in latently infected individuals with no evidence of virus disease or dissemination