Search results for "PATHOGEN"
showing 7 items of 1657 documents
Vaginal infection of mice with HSV type 2 variant ER−: A new animal model for human primary genital HSV type 2 infections
1992
Abstract Studying the pathogenesis of vaginal infections in mice with two variants of Herpes simplex virus type 2 (HSV-2) strain ER we observed that both variants ER+ and ER− caused severe vaginitis but only ER+ invaded the CNS leading to lethal neurological disease. In contrast, mice infected with ER− cleared the virus from the vagina and recovered from infection. ER+ and ER− expressed equal levels of thymidine kinase (TK) indicating a TK-independent difference in neurovirulence. Using the non-neurovirulent variant ER−, we were able to investigate humoral immune responses late after infection. Vaginal infection with ER− suppressed serum antibody formation after a secondary systemic HSV-1 i…
Infection-induced chromatin modifications facilitate translocation of herpes simplex virus capsids to the inner nuclear membrane
2021
Herpes simplex virus capsids are assembled and packaged in the nucleus and move by diffusion through the nucleoplasm to the nuclear envelope for egress. Analyzing their motion provides conclusions not only on capsid transport but also on the properties of the nuclear environment during infection. We utilized live-cell imaging and single-particle tracking to characterize capsid motion relative to the host chromatin. The data indicate that as the chromatin was marginalized toward the nuclear envelope it presented a restrictive barrier to the capsids. However, later in infection this barrier became more permissive and the probability of capsids to enter the chromatin increased. Thus, although …
Genome sequence of SeIV-1, a novel virus from the Iflaviridae family infective to Spodoptera exigua
2011
Analysis of the transcriptome of Spodoptera exigua larvae revealed the presence of several ESTs with homology to virus of the order Picornavirales and with the highest similarity to Infectious flacherie virus (Iflaviridae) that infects Bombyx mori larvae. Iflaviridae is a recently defined family of insect-infecting viruses that consist of positive single strand RNA genomes translated into a single polyprotein of around 3000 amino acids long. Using the sequence information derived from the obtained ESTs, we have completed the genomic sequence of this virus. The novel S. exigua iflavirus (SeIV-1) has a genome of 10.3 kb and codes for a 3222 aa polyprotein. Expression analysis has revealed the…
Single amino acid substitutions in the glycoprotein B carboxy terminus influence the fusion from without property of herpes simplex virus type 1.
1995
Syncytial mutations of herpes simplex virus type 1 (HSV-1) strains ANG, ANG path, HFEM, tsB5 and HSZP cause extensive cell fusion and were mapped to the cytoplasmic domain of glycoprotein B (gB), within the syn 3 locus. These strains are so far the only ones which show the phenotype ‘fusion from without’ (FFWO): 60 min after infection with high m.o.i., cells in a tissue culture are fused without transcription and translation of the viral genome. In this report we detected, using the recombinants 27/III and K-7, that an amino acid exchange from Ala to Val at aa position 854 of gB is the main determinant for FFWO activity of strains ANG, ANG path and recombinant K-7. The transfer of this muta…
Human Papillomavirus Type 16 E7 Peptide-Directed CD8+ T Cells from Patients with Cervical Cancer Are Cross-Reactive with the Coronavirus NS2 Protein
2003
ABSTRACTHuman papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are required for cellular transformation and represent candidate targets for HPV-specific and major histocompatibility complex class I-restricted CD8+-T-cell responses in patients with cervical cancer. Recent evidence suggests that cross-reactivity represents the inherent nature of the T-cell repertoire. We identified HLA-A2 binding HPV16 E7 variant peptides from human, bacterial, or viral origin which are able to drive CD8+-T-cell responses directed against wild-type HPV16 E7 amino acid 11 to 19/20 (E711-19/20) epitope YMLDLQPET(T) in vitro. CD8+T cells reacting to the HLA-A2-presented peptide from HPV16 E711-19(20)recogni…
Clathrin- and Caveolin-Independent Entry of Human Papillomavirus Type 16—Involvement of Tetraspanin-Enriched Microdomains (TEMs)
2008
BACKGROUND: Infectious entry of human papillomaviruses into their host cells is an important step in the viral life cycle. For cell binding these viruses use proteoglycans as initial attachment sites. Subsequent transfer to a secondary receptor molecule seems to be involved in virus uptake. Depending on the papillomavirus subtype, it has been reported that entry occurs by clathrin- or caveolin-mediated mechanisms. Regarding human papillomavirus type 16 (HPV16), the primary etiologic agent for development of cervical cancer, clathrin-mediated endocytosis was described as infectious entry pathway. METHODOLOGY/PRINCIPAL FINDINGS: Using immunofluorescence and infection studies we show in contra…
A New Phylogenetic Framework for the Animal-Adapted
2018
Tuberculosis (TB) affects humans and other animals and is caused by bacteria from the Mycobacterium tuberculosis complex (MTBC). Previous studies have shown that there are at least nine members of the MTBC infecting animals other than humans; these have also been referred to as ecotypes. However, the ecology and the evolution of these animal-adapted MTBC ecotypes are poorly understood. Here we screened 12,886 publicly available MTBC genomes and newly sequenced 17 animal-adapted MTBC strains, gathering a total of 529 genomes of animal-adapted MTBC strains. Phylogenomic and comparative analyses confirm that the animal-adapted MTBC members are paraphyletic with some members more closely relate…