Effects of Streptococcal Cell Wall Fragments on Phagocytosis and Tissue Culture Cells

1970 ◽  
Vol 1 (3) ◽  
pp. 232-242
Author(s):  
Joe M. Jones ◽  
John H. Schwab
Keyword(s):  
Cell Wall ◽  
Mammalian Cells ◽  
Rabbit Kidney ◽  
Streptococcal Cell Wall ◽  
Cell Monolayers ◽  
Culture Cells ◽  
Group A ◽  
Group D

Group A streptococcal cell wall fragments inhibited phagocytosis of unrelated particles by rabbit polymorphonuclear leukocytes and inhibited the growth of rabbit kidney cells in vitro. Activity was associated with the mucopeptide moiety. Whole streptococci or the cytoplasmic fraction were less effective than cell wall fragments. The cell wall fragments of group D streptococci, Bacillus megaterium , and Escherichia coli were inactive. The inhibition of phagocytosis illustrates one way in which microbial components may influence the immune response. The toxicity for tissue cultures of rabbit kidney cell monolayers was greatest during the phase of active cell division. This appears to be a direct toxic effect of cell wall fragments on mammalian cells and may be related to the in vivo injury previously reported for streptococcal cell walls.

scholarly journals SpyAD, a Moonlighting Protein of Group A Streptococcus Contributing to Bacterial Division and Host Cell Adhesion

2014 ◽  
Vol 82 (7) ◽  
pp. 2890-2901 ◽  
Author(s):  
Marilena Gallotta ◽  
Giovanni Gancitano ◽  
Giampiero Pietrocola ◽  
Marirosa Mora ◽  
Alfredo Pezzicoli ◽  
...  
Keyword(s):  
Cell Division ◽  
Mammalian Cells ◽  
Group A Streptococcus ◽  
Host Cells ◽  
Knockout Mutant ◽  
Content Type ◽  
Moonlighting Protein ◽  
Group A

ABSTRACTGroup A streptococcus (GAS) is a human pathogen causing a wide repertoire of mild and severe diseases for which no vaccine is yet available. We recently reported the identification of three protein antigens that in combination conferred wide protection against GAS infection in mice. Here we focused our attention on the characterization of one of these three antigens, Spy0269, a highly conserved, surface-exposed, and immunogenic protein of unknown function. Deletion of thespy0269gene in a GAS M1 isolate resulted in very long bacterial chains, which is indicative of an impaired capacity of the knockout mutant to properly divide. Confocal microscopy and immunoprecipitation experiments demonstrated that the protein was mainly localized at the cell septum and could interactin vitrowith the cell division protein FtsZ, leading us to hypothesize that Spy0269 is a member of the GAS divisome machinery. Predicted structural domains and sequence homologies with known streptococcal adhesins suggested that this antigen could also play a role in mediating GAS interaction with host cells. This hypothesis was confirmed by showing that recombinant Spy0269 could bind to mammalian epithelial cellsin vitroand thatLactococcus lactisexpressing Spy0269 on its cell surface could adhere to mammalian cellsin vitroand to mice nasal mucosain vivo. On the basis of these data, we believe that Spy0269 is involved both in bacterial cell division and in adhesion to host cells and we propose to rename this multifunctional moonlighting protein as SpyAD (StreptococcuspyogenesAdhesion andDivision protein).

Abstract 3: Apolipoprotein A-I Inhibits Streptococcal Cell Wall-Induced Arthritis in the Rat in an ABCA1-dependent Manner

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Ben J Wu ◽  
Kwok L Ong ◽  
Sudichhya Shrestha ◽  
Kang Chen ◽  
Philip J Barter ◽  
...  
Keyword(s):  
Cell Wall ◽  
Inflammatory Cytokine ◽  
Density Lipoprotein ◽  
Joint Inflammation ◽  
Chronic Inflammatory Disease ◽  
Dependent Manner ◽  
Tlr2 Expression ◽  
Streptococcal Cell Wall

Introduction. Arthritis is a chronic inflammatory disease characterized by joint inflammation and destruction, reduced high-density lipoprotein (HDL) levels, and increased cardiovascular risk. Objective To determine if apolipoprotein (apo) A-I, the main HDL apolipoprotein, prevents joint inflammation in arthritis. Methods and Results In vivo: Arthritis was induced in female Lewis rats with a single 15 mg/kg intraperitoneal streptococcal cell wall peptidoglycan-polysaccharide (PG-PS) injection and quantified as a combined forepaw and hindpaw inflammation score. Arthritis progressed from an initial, acute phase of joint inflammation during the first 4 days post-PG-PS administration to remission by day 8, followed by chronic joint inflammation up to sacrifice at day 21. Two intravenous infusions of lipid-free apoA-I (8 mg/kg) 24 h pre- and 24 h post-PG-PS injection reduced the acute and chronic joint inflammation by 63±9% at day 3 and by 61±8% at day 21. Infusion of apoA-I at days 7, 9 and 11 post-PG-PS injection reduced the chronic response by 43±11% at day 21. ApoA-I infusions at 24 h prior to and at days 1, 7, 9, 11 post-PG-PS injection reduced joint inflammation by 61±5% at day 3 and by 90±5% at day 21 (p<0.05 for all vs saline infusion). These beneficial effects of apoA-I were accompanied by a reduced inflammatory white blood cell count, reduced pro-inflammatory cytokine levels in synovial fluid, and reduced macrophage accumulation, toll-like receptor 2 (TLR2) and inflammatory cytokine expression in synovial tissue. In vitro: Human monocyte-derived macrophages (HMDMs) were pre-incubated with lipid-free apoA-I, then stimulated with PG-PS (20 μg/mL). Pre-incubation with apoA-I inhibited PG-PS-induced TLR2 and MyD88, a TLR2 adapter protein, expression. Nuclear factor-κB activation and pro-inflammatory cytokine production were also attenuated. These anti-inflammatory effects of apoA-I were abolished in HMDMs transfected with ATP-binding cassette transporter 1 (ABCA1) siRNA. Conclusions These findings establish that apoA-I attenuates PG-PS induced arthritis in the rat. These effects may involve ABCA-1 and inhibition of TLR2 expression and activation.

scholarly journals Streptolysin-induced endoplasmic reticulum stress promotes group A streptococcal in vivo biofilm formation and necrotizing fasciitis

2017 ◽  
Author(s):  
Anuradha Vajjala ◽  
Debabrata Biswas ◽  
Kelvin Kian Long Chong ◽  
Wei Hong Tay ◽  
Emanuel Hanski ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Er Stress ◽  
Necrotizing Fasciitis ◽  
Biofilm Formation ◽  
Mammalian Cells ◽  
Chronic Infections ◽  
Group A

AbstractGroup A Streptococcus (GAS) is a human pathogen that causes infections ranging from mild to fulminant and life-threatening. Biofilms have been implicated in acute GAS soft-tissue infections such as necrotizing fasciitis (NF). However, most in vitro models used to study GAS biofilms have been designed to mimic chronic infections and insufficiently recapitulate in vivo conditions and the host-pathogen interactions that might influence biofilm formation. Here we establish and characterize an in vitro model of GAS biofilm development on mammalian cells that simulates microcolony formation observed in a murine model of human NF. We show that on mammalian cells, GAS forms dense aggregates that display hallmark biofilm characteristics including a three-dimensional architecture and enhanced tolerance to antibiotics. In contrast to abiotic-grown biofilms, host-associated biofilms require the expression of secreted GAS streptolysins O and S (SLO, SLS) resulting in the release of a host-associated biofilm promoting-factor(s). Supernatants from GAS-infected mammalian cells or from cells treated with endoplasmic reticulum (ER) stressors restore biofilm formation to an SLO and SLS null mutant that is otherwise attenuated in biofilm formation on cells, together suggesting a role for streptolysin-induced ER stress in this process. In an in vivo mouse model, the streptolysin-null mutant is attenuated in both microcolony formation and bacterial spread, but pre-treatment of softtissue with an ER-stressor restores the ability of the mutant to form wild type like microcolonies that disseminate throughout the soft tissue. Taken together, we have identified a new role of streptolysin-driven ER stress in GAS biofilm formation and NF disease progression.Significance StatementAlthough it is well-accepted that bacterial biofilms are associated with many chronic infections, little is known about the mechanisms by which group A Streptococcus (GAS) biofilms contribute to acute soft tissue-invasive diseases like necrotizing fasciitis (NF). In this study, we establish a physiologically relevant in vitro model to study GAS biofilm formation on mammalian cells and validate our findings in a mouse model that mimics human NF. This study demonstrates a novel role of GAS streptolysin-mediated ER stress in the development and spread of GAS biofilms in acute softtissue infections. We also show that biofilm formation depends on the release of a host-associated factor that promotes microcolony formation and GAS dissemination in vivo.

Ameliorative effects of Lactobacillus against Aflatoxin B1

2024 ◽  
Vol 84 ◽  
Author(s):  
R. Yasmeen ◽  
B. Zahid ◽  
S. Alyas ◽  
R. Akhtar ◽  
N. Zahra ◽  
...  
Keyword(s):  
Aflatoxin B1 ◽  
Aqueous Environment ◽  
Serum Total Protein ◽  
Ameliorative Effect ◽  
Group A ◽  
Cell Fractions ◽  
Group D ◽  
Better Than

Abstract Lactobacilli are probiotics with Aflatoxin (AF) detoxification ability, found in fermented products, GIT of animals and environment. Purpose of this study was to investigate the ability of broiler isolates of Lactobacillus against Aflatoxin B1 (AFB1). For this purpose, 5 isolates of Lactobacillus from broiler gut were incubated with 100 ppb AFB1 in aqueous environment and effect of different parameters (cell fractions, time, temperature, pH) on detoxification was determined by HPLC. The ameliorative effect of Lactobacillus salivarius (LS) against AFB1 was studied in broiler. The results revealed that LS (CR. 4) showed the best results (in vitro) as compared to other isolates (L. salivarius (CR. 3, CR, 4), L. agilis (CE. 2.1, CE. 3.1) and L. crispatus (CE. 28). Cell debris of CR. 4 showed significantly higher detoxification (P<0.05). Maximum amount of AFB1 was detoxified at 30°C (97%), pH 4.0 (99%) and 6 h (99.97%). In vivo study showed that AFB1 decreased weight gain (1,269 ± 0.04 gm/ bird), feed consumed (2,161 ± 0.08 gm/ bird), serum total protein (2.42 ± 0.34 gm/ dl), serum albumin (0.5 ± 0.2 2 gm/dl) and antibody titer (4.2 ± 0.83). Liver function enzymes were found (alanine transaminase (ALT): 32 ± 10.7 U/L) and aspartate transaminase (AST): 314.8 ± 27 U/L) elevated in AFB1 fed broilers. Treatment with 1% LS not only decreased the toxic effects of AFB1 (group D) but also improved the overall health of broilers due to its probiotic effects (p<0.05) as compared to control negative (group A). The detoxification ability of LS was better than commercial binder (CB) (0.2% Protmyc). It was concluded that detoxification of AFB1 by Lactobacillus was strain, temperature, pH and time dependent. LS has detoxification ability against AFB1 in vivo.

scholarly journals Repair of bone defects with prefabricated vascularized bone grafts and double-labeled bone marrow-derived mesenchymal stem cells in a rat model

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Xiao-Rui Jiang ◽  
Hui-Ying Yang ◽  
Xin-Xin Zhang ◽  
Guo-Dong Lin ◽  
Yong-Chun Meng ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Vascular Bundle ◽  
Bone Defects ◽  
Group A ◽  
Group D ◽  
Vascularized Bone

Abstract This study aims to investigate the repair of bone defects with prefabricated vascularized bone grafts and double-labeled bone marrow-derived mesenchymal stem cells (BMSCs) in a rat model. BMSCs were separated from rat bone marrow. LTR-CMVpro-RFP and LTR-CMVpro-GFP were transfected into the BMSCs for in vitro and in vivo tracking. BMSCs-RFP and BMSCs-GFP were induced into endothelial progenitor cells (EPCs) and osteoblasts (OBs). Rats were divided into five groups: Group A: in vitro prefabrication with EPCs-RFP + in vivo prefabrication with arteriovenous vascular bundle + secondary OBs-GFP implantation; Group B: in vitro prefabrication with EPCs-RFP + secondary OBs-GFP implantation; Group C: in vivo prefabrication with arteriovenous vascular bundle + secondary OBs-GFP implantation; Group D: implantation of EPCs-RFP + implantation of with arteriovenous vascular bundle + simultaneous OBs-GFP implantation; Group E: demineralized bone matrix (DBM) grafts (blank control). Among five groups, Group A had the fastest bone regeneration and repair, and the regenerated bone highly resembled normal bone tissues; Group D also had fast bone repair, but the repair was slightly slower than Group A. Therefore, in vitro prefabrication with EPCs-RFP plus in vivo prefabrication with arteriovenous vascular bundle and secondary OBs-GFP implantation could be the best treatment for bone defect.

138 COMPARISON OF KINETICS AND PATTERNS OF THE FIRST CLEAVAGE OF IN VIVO AND IN VITRO-MATURED HOLSTEIN OOCYTES AFTER IN VITRO FERTILIZATION WITH X-SORTED SPERM

2014 ◽  
Vol 26 (1) ◽  
pp. 182
Author(s):  
S. Matoba ◽  
S. Sugimura ◽  
H. Matsuda ◽  
Y. Aikawa ◽  
M. Ohtake ◽  
...  
Keyword(s):  
Calf Serum ◽  
Time Lapse ◽  
Developmental Competence ◽  
High Rate ◽  
Holstein Cows ◽  
Group A ◽  
Group B ◽  
Group D

Previously, it was reported that a high rate of good quality blastocysts were produced by IVF of in vivo-matured oocytes, obtained by ovum pick up (OPU) after superstimulation in Holstein cows, using X-sorted sperm (Matoba et al. 2012 Reprod. Domest. Anim. 47, 515). In this system, an early first cleavage within 28 h after IVF was found to be a potent marker for the selection of embryos with high developmental competence (Matoba et al. 2013 Reprod. Fertil. Dev. 25, 266). However, we have limited knowledge on the timing and normality of embryonic cleavages in in vitro-matured oocytes after IVF. The purpose of the present study was to compare the kinetics and patterns of the first cleavage of in vivo- and in vitro-matured bovine oocytes after IVF with X-sorted sperm. In vivo-matured oocytes (Group A) were collected by OPU from non-lactating Holstein cows just before ovulation after superstimulation. Immature oocytes were either collected by OPU without hormonal treatment or by aspiration of ovaries at the local abattoir and matured in vitro (Group B or C). All the oocytes were inseminated with 5 × 106 sperm mL–1 of X-sorted sperm, except half of oocytes in Group C inseminated by non-sorted sperm (Group D) and cultured in CR1aa supplemented with 5% calf serum and 0.25 mg mL–1 of linoleic acid albumin at 38.5°C in 5% CO2, 5% O2, and 90% N2 for 216 h. Embryo kinetics were observed individually using a microwell culture dish and time-lapse cinematography (Sugimura et al. 2010 Biol. Reprod. 83, 970–978). Photographs of each embryo were taken in every 15 min during the IVC period and analysed by time-lapse cinematography software. Cleavage pattern was categorized as normal (2 even blastomeres without fragment or protrusion) or abnormal (2 uneven blastomeres, with fragment or protrusion and those dividing into 3–5 blastomeres) at the first cleavage. Data were analysed by ANOVA, chi-squared, or discriminant function. A total of 268 cleaved embryos were used. The blastocyst rate in Group A was higher than in Groups B and C (61.3 v. 40.0 and 25.0%, respectively; P < 0.05). The timing of first cleavage was longer in Group A compared with Groups C and D (28.3 ± 3.8 v. 27.6 ± 3.8 and 26.7 ± 1.9 h, respectively) and in Group B (28.1 ± 4.0 h) compared with in Group D (P < 0.05). Higher rates of normal cleavage were observed in Groups A, B, and D than in Group C (53.5, 44.4, and 54.8 v. 16.7%, respectively; P < 0.01). The frequency of blastocysts derived from the early (28.3 h) and normal pattern cleaving oocytes were greater in Groups A and B than in Group C (29.0 and 20.0 v. 8.3%, respectively; P < 0.05) and similar in Group D (22.6%). Our results reveal that IVF embryos produced from in vivo-matured oocytes with sex-sorted sperm had superior normality than those produced from in vitro-matured oocytes and similar normality to embryos inseminated with non-sorted sperm. Supported by the Research and Development projects for application in promoting new policy of agriculture, forestry and fisheries (22016) and by JSPS and HAS under the Japan-Hungary Research Cooperative Program.

scholarly journals Intrahepatic Arterial Delivery of Sorafenib Eluting Beads: A Pharmacokinetics Study

2020 ◽  
Vol 3 (2) ◽  
pp. 17
Author(s):  
Eerdunbagena Ning ◽  
Zhijun Wang
Keyword(s):  
Liver Tissue ◽  
Slow Release ◽  
Normal Liver ◽  
In Vivo Study ◽  
Pharmacokinetics Study ◽  
Group A ◽  
Group B ◽  
Group D

 Objective: To determine the slow-release effect of Sorafenib carried beads and its impact on the normal liver of dogs. Materials and Methods: (1) To obtain the maximal drug-carrying of beads, different sizes of beads (300-500 μm and 500-700 μm) were tried. Five bottles of different sizes of beads were added into 75% solution of Sorafenid-alcohol with different concentrations: Bottle a,50mg/20ml; Bottle b, 100mg/20ml; Bottle c, 100 mg/40ml; Bottle d, 200mg/40m; Bottle e, 250mg/50ml. (2) In vivo study: 12 dogs were randomly divided into four groups [group A, Sorafenib carried bead (500-700μm); group B, only bead (300-500μm) ; group C, Lipiodol-sorafenib and four dogs in each group. Each group was treated with TAE with emulsion mentioned above. Sorafenib concentration in plasma and liver tissue was determined with HPLC respectively. Result: (1) In vitro research: Sorafenib can be dissolved into 75% alcohol and the best concentration for drug-carrying was 100mg/20ml. (2) In vivo study: ① Compared with group D, the Cmax and AUC in plasma in group A and B has a significant statistics difference(p<0.05). ② Sorafenib concentration in liver tissue could be determined in group A in the 3rd day and even after one week while it could not be determined in group D. Conclusion: Sorafenib can be carried in DC-Bead in a certain condition. Compared with emulsion with Sorafenib and lipiodol, DC-bead has a definite slow-release function and it is superior to lipiodol.

scholarly journals Higher immunoglobulin production in conjugated linoleic acid-supplemented rats during gestation and suckling

2009 ◽  
Vol 102 (6) ◽  
pp. 858-868 ◽  
Author(s):  
Carolina Ramírez-Santana ◽  
Francisco J. Pérez-Cano ◽  
Cristina Castellote ◽  
Margarida Castell ◽  
Montserrat Rivero ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Oral Administration ◽  
Conjugated Linoleic Acid ◽  
Wistar Rats ◽  
Reference Group ◽  
Standard Diet ◽  
Group A ◽  
Group D

Conjugated linoleic acid (CLA) has been reported to exert beneficial physiological effects on body composition and the immune system. However, little information is available on the influence of CLA on immune function during early life periods. The present study evaluates the effect of feeding an 80:20 mixture of cis-9, trans-11- and trans-10, cis-12-CLA isomers during gestation and suckling on the systemic immune response of weaned Wistar rats. Pups received dietary CLA from dams through the placental barrier and during suckling by breast milk (group A) or by oral administration (group B). Pups from group C only received CLA during suckling by oral administration. Group D constituted the reference group. Milk from dams fed the CLA diet had a high content of CLA and higher IgA and IgG concentrations than rats fed the standard diet. The plasma of pups from groups A, B and C showed six, twelve and nine times higher content of the cis-9, trans-11-CLA isomer than that of the group D pups. Rats from group A exhibited higher serum IgG concentrations than rats from the rest of the groups (22·14 (sem 2·14) v. about 5 mg/ml; P < 0·05), whereas rats from groups A and B showed approximately 2-fold higher splenocyte IgM production than rats from groups C and D. However, CLA supplementation did not influence significantly the splenocyte proliferative response or cytokine secretion. Supplementation during gestation and suckling with an 80:20 cis-9, trans-11–trans-10, cis-12 CLA mix enhances the production of the main in vivo and in vitro Ig isotypes in Wistar rats.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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