Human fibroblast interferon in tears of patients with picornavirus epidemic conjunctivitis

1980 ◽  
Vol 29 (3) ◽  
pp. 995-998
Author(s):  
M P Langford ◽  
M Yin-Murphy ◽  
Y M Ho ◽  
J C Barber ◽  
S Baron ◽  
...  
Keyword(s):  
Host Defense ◽  
Human Fibroblast ◽  
Natural Infection ◽  
Local Site ◽  
Early Appearance ◽  
Important Host ◽  
Interferon Activity ◽  
Mouse Cells ◽  
Antigenic Type

We report the levels of coxsackievirus type A24 (CA24) and the levels and type of interferon produced early during naturally acquired picornavirus epidemic conjunctivitis. Virus levels ranging from 10(1.8) to 10(5.8) 50% tissue culture infective doses per ml were detected in 29 of 37 acute (collected 1 to 4 days after onset of conjunctivitis) tear samples. Interferon (10(1.5) to 10(3.3) U/ml) was detected in 12 of 29 tear samples collected on day 1, in 2 of 6 tear samples collected on day 2, and in 1 tear sample collected on day 3 after onset of conjunctivitis. The interferon activity in pooled tear samples was completely neutralized by antiserum against human fibroblast interferon, stable at pH 2.0, and active against different viruses. In addition, the interferon activity in tears, like human fibroblast and leukocyte interferons produced in vitro, protected human and rabbit, but not mouse, cells. This is the first report of production and identification of the antigenic type of interferon induced by an enterovirus during natural infection. The early appearance of fibroblast interferon suggests that it may be an important host defense at the local site of implantation against this and possibly other enterovirus infections.

Some Structural Features of Metaphase Chromosomes of Mice and Men

1967 ◽  
Vol 25 ◽  
pp. 190-191
Author(s):  
Godfrey C. Hoskins ◽  
Betty B. Hoskins
Keyword(s):  
Electron Microscopy ◽  
Electron Micrographs ◽  
Structural Features ◽  
Metaphase Chromosomes ◽  
The Future ◽  
Of Mice And Men ◽  
Mouse Cells ◽  
Human And Mouse

Metaphase chromosomes from human and mouse cells in vitro are isolated by micrurgy, fixed, and placed on grids for electron microscopy. Interpretations of electron micrographs by current methods indicate the following structural features.Chromosomal spindle fibrils about 200Å thick form fascicles about 600Å thick, wrapped by dense spiraling fibrils (DSF) less than 100Å thick as they near the kinomere. Such a fascicle joins the future daughter kinomere of each metaphase chromatid with those of adjacent non-homologous chromatids to either side. Thus, four fascicles (SF, 1-4) attach to each metaphase kinomere (K). It is thought that fascicles extend from the kinomere poleward, fray out to let chromosomal fibrils act as traction fibrils against polar fibrils, then regroup to join the adjacent kinomere.

scholarly journals Mechanistic Fingerprinting Reveals Kinetic Signatures of Resistance to Daptomycin and Host Defense Peptides in Streptococcus mitis-oralis

Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 404
Author(s):  
Michael R. Yeaman ◽  
Liana C. Chan ◽  
Nagendra N. Mishra ◽  
Arnold S. Bayer
Keyword(s):  
Flow Cytometry ◽  
Host Defense ◽  
Durable Resistance ◽  
Cross Resistance ◽  
Streptococcus Mitis ◽  
Host Defense Peptides ◽  
Strain Pair ◽  
Defense Peptides

Streptococcus mitis-oralis (S. mitis-oralis) infections are increasingly prevalent in specific populations, including neutropenic cancer and endocarditis patients. S. mitis-oralis strains have a propensity to evolve rapid, high-level and durable resistance to daptomycin (DAP-R) in vitro and in vivo, although the mechanism(s) involved remain incompletely defined. We examined mechanisms of DAP-R versus cross-resistance to cationic host defense peptides (HDPs), using an isogenic S. mitis-oralis strain-pair: (i) DAP-susceptible (DAP-S) parental 351-WT (DAP MIC = 0.5 µg/mL), and its (ii) DAP-R variant 351-D10 (DAP MIC > 256 µg/mL). DAP binding was quantified by flow cytometry, in-parallel with temporal (1–4 h) killing by either DAP or comparative prototypic cationic HDPs (hNP-1; LL-37). Multicolor flow cytometry was used to determine kinetic cell responses associated with resistance or susceptibility to these molecules. While overall DAP binding was similar between strains, a significant subpopulation of 351-D10 cells hyper-accumulated DAP (>2–4-fold vs. 351-WT). Further, both DAP and hNP-1 induced cell membrane (CM) hyper-polarization in 351-WT, corresponding to significantly greater temporal DAP-killing (vs. 351-D10). No strain-specific differences in CM permeabilization, lipid turnover or regulated cell death were observed post-exposure to DAP, hNP-1 or LL-37. Thus, the adaptive energetics of the CM appear coupled to the outcomes of interactions of S. mitis-oralis with DAP and selected HDPs. In contrast, altered CM permeabilization, proposed as a major mechanism of action of both DAP and HDPs, did not differentiate DAP-S vs. DAP-R phenotypes in this S. mitis-oralis strain-pair.

scholarly journals Chemically defined and xeno-free culture condition for human extended pluripotent stem cells

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bei Liu ◽  
Shi Chen ◽  
Yaxing Xu ◽  
Yulin Lyu ◽  
Jinlin Wang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Pluripotent Stem Cells ◽  
Culture Condition ◽  
Human Fibroblast ◽  
Culture System ◽  
Disease Modeling ◽  
Directed Differentiation

AbstractExtended pluripotent stem (EPS) cells have shown great applicative potentials in generating synthetic embryos, directed differentiation and disease modeling. However, the lack of a xeno-free culture condition has significantly limited their applications. Here, we report a chemically defined and xeno-free culture system for culturing and deriving human EPS cells in vitro. Xeno-free human EPS cells can be long-term and genetically stably maintained in vitro, as well as preserve their embryonic and extraembryonic developmental potentials. Furthermore, the xeno-free culturing system also permits efficient derivation of human EPS cells from human fibroblast through reprogramming. Our study could have broad utility in future applications of human EPS cells in biomedicine.

scholarly journals Naturally induced humoral response against Plasmodium vivax reticulocyte binding protein 2P1

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Jenni Hietanen ◽  
Anongruk Chim-ong ◽  
Jetsumon Sattabongkot ◽  
Wang Nguitragool
Keyword(s):  
Plasmodium Vivax ◽  
Vaccine Development ◽  
Natural Infection ◽  
Humoral Response ◽  
Human Antibody ◽  
Asymptomatic Carriers ◽  
Erythrocyte Invasion ◽  
Human Proteins ◽  
Human Immune Response

Abstract Background Plasmodium vivax is the most prevalent malaria parasite in many countries. A better understanding of human immunity to this parasite can provide new insights for vaccine development. Plasmodium vivax Reticulocyte Binding Proteins (RBPs) are key parasite proteins that interact with human proteins during erythrocyte invasion and are targets of the human immune response. The aim of this study is to characterize the human antibody response to RBP2P1, the most recently described member of the RBP family. Methods The levels of total IgG and IgM against RBP2P1 were measured using plasmas from 68 P. vivax malaria patients and 525 villagers in a malarious village of western Thailand. The latter group comprises asymptomatic carriers and healthy uninfected individuals. Subsets of plasma samples were evaluated for anti-RBP2P1 IgG subtypes and complement-fixing activity. Results As age increased, it was found that the level of anti-RBP2P1 IgG increased while the level of IgM decreased. The main anti-RBP2P1 IgG subtypes were IgG1 and IgG3. The IgG3-seropositive rate was higher in asymptomatic carriers than in patients. The higher level of IgG3 was correlated with higher in vitro RBP2P1-mediated complement fixing activity. Conclusions In natural infection, the primary IgG response to RBP2P1 was IgG1 and IgG3. The predominance of these cytophilic subtypes and the elevated level of IgG3 correlating with complement fixing activity, suggest a possible role of anti-RBP2P1 antibodies in immunity against P. vivax.

Mouse chick chimera: a new model to study the in ovo developmental potentialities of mammalian somites

Development ◽  
1995 ◽  
Vol 121 (6) ◽  
pp. 1705-1718 ◽  
Author(s):  
J. Fontaine-Perus ◽  
V. Jarno ◽  
C. Fournier le Ray ◽  
Z. Li ◽  
D. Paulin
Keyword(s):  
In Vitro Cultures ◽  
Mouse Embryos ◽  
Limb Muscle ◽  
Mammalian Development ◽  
In Ovo ◽  
Gene Coding ◽  
Myogenic Stem Cells ◽  
Mouse Cells ◽  
Beta Galactosidase

Chimeras were prepared by transplanting somites from 9-day post-coitum mouse embryos or somitic dermomyotomes from 10-day post-coitum mouse embryos into 2-day-old chick embryos at different axial levels. Mouse somitic cells then differentiated in ovo in dermis, cartilage and skeletal muscle as they normally do in the course of development and were able to migrate into chick host limb. To trace the behavior of somitic myogenic stem cells more closely, somites arising from mice bearing a transgene of the desmin gene linked to a reporter gene coding for Escherichia coli beta-galactosidase (lacZ) were grafted in ovo. Interestingly, the transgene was rapidly expressed in myotomal muscles derived from implants. In the limb muscle mass, positive cells were found several days after implantation. Activation of desmin nls lacZ also occurred in in vitro cultures of somite-derived cells. Our experimental method facilitates investigation of the mechanisms of mammalian development, allowing the normal fate of implanted mouse cells to be studied and providing suitable conditions for identification of descendants of genetically modified cells.

Mouse cells contain two distinct ras gene mRNA species that can be translated into a p21 onc protein

1982 ◽  
Vol 2 (11) ◽  
pp. 1339-1345
Author(s):  
R W Ellis ◽  
D DeFeo ◽  
M E Furth ◽  
E M Scolnick
Keyword(s):  
Normal Mouse ◽  
Velocity Sedimentation ◽  
Ras Gene ◽  
Mrna Species ◽  
P21 Ras ◽  
Murine Sarcoma Virus ◽  
Sarcoma Virus ◽  
Mouse Cells ◽  
Murine Sarcoma

The Kirsten (Ki) and Harvey (Ha) strains of murine sarcoma virus encode a 21,000-dalton protein (p21 ras) which is the product of the transforming gene of these viruses. Normal cells express low levels of p21 ras encoded by cellular genes (Ki-ras and Ha-ras) homologous to the Ki and Ha murine sarcoma virus transformation genes. A bone marrow-derived mouse cell line, 416B, has been shown to express unusually high levels of p21 ras. In this manuscript, we investigated the molecular biology of p21 ras gene expression in 416B and other normal mouse cells. We identified four distinct polyadenylated and polysome-associated RNAs, two related to Ki-ras and two to Ha-ras. The levels in 416B cells of the two Ki-ras RNAs, sized 5.2 and 2.0 kilobases, were both elevated approximately 25-fold over levels found in normal mouse cells; there was no corresponding change in 416B cells in the levels of the two Ha-ras RNAs. We partially purified the two Ki-ras mRNAs and separated them by velocity sedimentation in sucrose density gradients. Both the 5.2- and 2.0-kilobase mRNAs could be translated in vitro into p21 ras. These results show that a cellular onc protein can be translated from two distinct cellular mRNA species.

In vitro and in vivo modulation of the immune response by human fibroblast interferon (HFI)

1980 ◽  
Vol 2 (3) ◽  
pp. 159 ◽  
Author(s):  
B. Serrou ◽  
D. Cupissol ◽  
L. Gauci ◽  
C. Thierry ◽  
J. Caraux ◽  
...  
Keyword(s):  
Immune Response ◽  
Human Fibroblast

scholarly journals DNA methylation specifies chromosomal localization of MeCP2.

1996 ◽  
Vol 16 (1) ◽  
pp. 414-421 ◽  
Author(s):  
X Nan ◽  
P Tate ◽  
E Li ◽  
A Bird
Keyword(s):  
Dna Methylation ◽  
Cultured Cells ◽  
Centromeric Heterochromatin ◽  
Intact Protein ◽  
Chromosomal Protein ◽  
Mouse Cells ◽  
Low Levels ◽  
Mutant Cells

MeCP2 is a chromosomal protein that is concentrated in the centromeric heterochromatin of mouse cells. In vitro, the protein binds preferentially to DNA containing a single symmetrically methylated CpG. To find out whether the heterochromatic localization of MeCP2 depended on DNA methylation, we transiently expressed MeCP2-LacZ fusion proteins in cultured cells. Intact protein was targeted to heterochromatin in wild-type cells but was inefficiently localized in mutant cells with low levels of genomic DNA methylation. Deletions within MeCP2 showed that localization to heterochromatin required the 85-amino-acid methyl-CpG binding domain but not the remainder of the protein. Thus MeCP2 is a methyl-CpG-binding protein in vivo and is likely to be a major mediator of downstream consequences of DNA methylation.

scholarly journals Porcine Choroid Plexus Epithelial Cells Induce Streptococcus suis Bacteriostasis In Vitro

2004 ◽  
Vol 72 (5) ◽  
pp. 3084-3087 ◽  
Author(s):  
Rüdiger A. Adam ◽  
Tobias Tenenbaum ◽  
Peter Valentin-Weigand ◽  
Maurice Laryea ◽  
Bernd Schwahn ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Bacterial Meningitis ◽  
Choroid Plexus ◽  
Host Defense ◽  
Streptococcus Suis ◽  
Active Role ◽  
Necrosis Factor Alpha ◽  
Ifn Γ ◽  
Choroid Plexus Epithelial

ABSTRACT The involvement of the choroid plexus in host defense during bacterial meningitis is unclear. Aiming to elucidate possible antibacterial mechanisms, we stimulated primary porcine choroid plexus epithelial cells (pCPEC) with proinflammatory cytokines and challenged them with various Streptococcus suis strains. In the supernatant of gamma interferon (IFN-γ)-stimulated pCPEC, streptococcal growth was markedly suppressed. Costimulation with tumor necrosis factor alpha enhanced this bacteriostatic effect, while supplementation of l-tryptophan completely eliminated it. We also demonstrate that an activation of indoleamine 2,3-dioxygenase in the pCPEC seems to be responsible for the IFN-γ-induced bacteriostasis. This supports the hypothesis of an active role of the choroid plexus in host defense against bacterial meningitis.

Basis for the Acquaisition of Malignant Potential by Mouse Cells Cultivated in vitro

Science ◽  
1968 ◽  
Vol 162 (3857) ◽  
pp. 1024-1026 ◽  
Author(s):  
S. A. Aaronson ◽  
G. J. Todaro
Keyword(s):  
Malignant Potential ◽  
Mouse Cells
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