Bindings of plasma proteins to streptococci of serological group L with special reference to their immunoglobulin G Fc-receptor activity

1988 ◽  
Vol 34 (1) ◽  
pp. 1-5 ◽  
Author(s):  
C. Lämmler ◽  
P. Schaufuß ◽  
C. Frede ◽  
H. Blobel
Keyword(s):  
Affinity Chromatography ◽  
Special Reference ◽  
Molecular Mass ◽  
Immunoglobulin G ◽  
Binding Sites ◽  
Plasma Proteins ◽  
Fc Receptors ◽  
Streptococcus Dysgalactiae ◽  
Serological Group ◽  
Ig G

Of 33 streptococcal cultures belonging to serological group L, all bound human immunoglobulin (Ig) G, fibrinogen, and fibronectin; 32 bound bovine IgG; 31 bound α2-macroglobulin; 5 bound albumin; and none bound either haptoglobin or IgA. The binding sites for IgG could be isolated from the L streptococci by trypsinization and purified by affinity chromatography on human IgG – Sepharose®. The purified Fc receptors reacted with IgG subclasses 1, 2, 3, 4 of humans, 1 and 2 of bovines, ovines, and caprines as well as a, b, c, and T of equines. They had a molecular mass of approximately 49 000 Da. Thus, the Fc receptors from L streptococci corresponded to type III Fc receptors of Streptococcus dysgalactiae.

scholarly journals Streptococcal inhibitor of complement-mediated lysis (SIC): an anti-inflammatory virulence determinant

Microbiology ◽  
2010 ◽  
Vol 156 (12) ◽  
pp. 3660-3668 ◽  
Author(s):  
Per Åkesson ◽  
Heiko Herwald ◽  
Magnus Rasmussen ◽  
Katarina HÅkansson ◽  
Magnus Abrahamson ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Binding Sites ◽  
Plasma Proteins ◽  
Blood Clotting ◽  
Protein Family ◽  
Contact Activation ◽  
Cell Binding ◽  
Clotting Time ◽  
Human Contact ◽  
Cell Binding Domain

Since the late 1980s, a worldwide increase of severe Streptococcus pyogenes infections has been associated with strains of the M1 serotype, strains which all secrete the streptococcal inhibitor of complement-mediated lysis (SIC). Previous work has shown that SIC blocks complement-mediated haemolysis, inhibits the activity of antibacterial peptides and has affinity for the human plasma proteins clusterin and histidine-rich glycoprotein; the latter is a member of the cystatin protein family. The present work demonstrates that SIC binds to cystatin C, high-molecular-mass kininogen (HK) and low-molecular-mass kininogen, which are additional members of this protein family. The binding sites in HK are located in the cystatin-like domain D3 and the endothelial cell-binding domain D5. Immobilization of HK to cellular structures plays a central role in activation of the human contact system. SIC was found to inhibit the binding of HK to endothelial cells, and to reduce contact activation as measured by prolonged blood clotting time and impaired release of bradykinin. These results suggest that SIC modifies host defence systems, which may contribute to the virulence of S. pyogenes strains of the M1 serotype.

Binding of α2-macroglobulin and haptoglobin to Actinomyces pyogenes

1985 ◽  
Vol 31 (7) ◽  
pp. 657-659 ◽  
Author(s):  
Christoph Lämmler ◽  
Gursharan S. Chhatwal ◽  
Hans Blobel
Keyword(s):  
Immunoglobulin G ◽  
Steric Hindrance ◽  
Binding Sites ◽  
Plasma Proteins ◽  
Binding Activity ◽  
The Other ◽  
Α2 Macroglobulin ◽  
Protein Nature ◽  
Actinomyces Pyogenes

All 25 cultures of Actinomyces pyogenes tested in the present study bound 125I-labelled human α2-macroglobulin with a mean binding of 65.6%. Thirteen cultures also bound 125I-labelled human haptoglobin with a mean of 51.5%. None interacted with fibrinogen, fibronectin, immunoglobulin G, or albumin. Twenty-eight cultures representing other species of actinomycetaceae did not show any interaction with α2-macroglobulin, haptoglobin, and other plasma proteins tested. The binding of α2-macroglobulin and haptoglobin to A. pyogenes was saturable and could be completely inhibited by the respective unlabelled plasma proteins. The binding of α2-macroglobulin could not be inhibited by unlabelled haptoglobin. On the other hand, α2-macroglóbulin blocked the binding of haptoglobin, possibly by steric hindrance. Treatment of the bacteria with trypsin reduced their binding activities for α2-macroglobulin and haptoglobin indicating the protein nature of the binding sites. Exposure to heat (1 h, 80 °C) significantly diminished the binding activity for haptoglobin, but not that for α2-macroglobulin. The binding of α2-macroglobulin and haptoglobin could be an important feature in the classification of A. pyogenes among the members of actinomycetaceae.

scholarly journals Treating Critically Ill Patients Experiencing SARS-CoV-2 Severe Infection with Ig-M and Ig-A Enriched Ig-G Infusion

Antibiotics ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 930
Author(s):  
Alberto Corona ◽  
Giuseppe Richini ◽  
Sara Simoncini ◽  
Marta Zangrandi ◽  
Monica Biasini ◽  
...  
Keyword(s):  
Immunoglobulin G ◽  
Standard Therapy ◽  
Severe Infection ◽  
Treated Group ◽  
Simplified Acute Physiology Score ◽  
Retrospective Case ◽  
Baseline Characteristics ◽  
Time Of Admission ◽  
Ig G ◽  
Control Study

SARS-CoV-2 in patients who need intensive care unit (ICU) is associated with a mortality rate ranging from 10 to 40–45%, with an increase in morbidity and mortality in presence of sepsis. We hypothesized that IgM and IgA enriched immunoglobulin G may support the sepsis-related phase improving patient outcome. We conducted a retrospective case–control study on 47 consecutive patients admitted to our ICU. At the time of admission, patients received anticoagulants (heparin sodium) together with the standard supportive treatment. We decided to add IgM and IgA enriched immunoglobulin G to the standard therapy. Patients receiving IgM and IgA enriched immunoglobulin G were compared with patients with similar baseline characteristics and treatment, receiving only standard therapy. The mortality resulted significantly higher in patients treated with standard therapy only (56.5 vs. 37.5%, p < 0.01) and, at day 7, the probability of dying was 3 times higher in this group. Variable life adjustment display (VLAD) was 2.4 and -2.2 (in terms of lives saved in relation with those expected and derived from Simplified Acute Physiology Score II) in the treated and not treated group, respectively. The treatment based on IgM and IgA enriched immunoglobulin G infusion seems to give an advantage on survival in SARS-CoV-2 severe infection.

scholarly journals Human Cytomegalovirus Open Reading Frame TRL11/IRL11 Encodes an Immunoglobulin G Fc-Binding Protein

2001 ◽  
Vol 75 (22) ◽  
pp. 11218-11221 ◽  
Author(s):  
Brendan N. Lilley ◽  
Hidde L. Ploegh ◽  
Rebecca S. Tirabassi
Keyword(s):  
Human Cytomegalovirus ◽  
Immunoglobulin G ◽  
Binding Protein ◽  
Fc Receptors ◽  
Binding Activity ◽  
Open Reading Frame ◽  
Membrane Glycoprotein ◽  
Type I ◽  
Reading Frame

ABSTRACT Several herpesviruses encode Fc receptors that may play a role in preventing antibody-mediated clearance of the virus in vivo. Human cytomegalovirus (HCMV) induces an Fc-binding activity in cells upon infection, but the gene that encodes this Fc-binding protein has not been identified. Here, we demonstrate that the HCMV AD169 open reading frame TRL11 and its identical copy, IRL11, encode a type I membrane glycoprotein that possesses IgG Fc-binding capabilities.

scholarly journals Heparin- and Zn2+-binding proteins from boar seminal plasma.

1999 ◽  
Vol 46 (4) ◽  
pp. 935-939 ◽  
Author(s):  
D Hołody ◽  
J Strzezek
Keyword(s):  
Amino Acid ◽  
Affinity Chromatography ◽  
Molecular Mass ◽  
Seminal Plasma ◽  
Binding Proteins ◽  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Heparin Binding ◽  
Sds Page ◽  
Protein Components

Low molecular mass, heparin-binding proteins from seminal plasma play an important role in gametes interaction whereas plasmatic Zn2+-binding proteins stabilize chromatin and plasmalemma structures and protect spermatozoa in the female reproductive tract. By means of affinity chromatography the heparin- and Zn2+-binding proteins were isolated from boar seminal plasma and both preparations were analyzed by reverse HPLC. Most of the proteins bound to heparine and Zn2+-ions were classified as spermadhesins. Three fractions binding exclusively Zn2+ were isolated. They differ in amino-acid composition, content of glucosamine and content of protein components revealed by SDS/PAGE.

Transferrin glycosylation in hypoxia

1991 ◽  
Vol 69 (4) ◽  
pp. 239-244 ◽  
Author(s):  
Erwin Regoeczi ◽  
J. Michael Kay ◽  
Paul A. Chindemi ◽  
Ouahida Zaimi ◽  
Kaye L. Suyama
Keyword(s):  
Affinity Chromatography ◽  
Sea Level ◽  
Anion Exchange ◽  
Immunoglobulin G ◽  
Lectin Affinity Chromatography ◽  
Lectin Affinity ◽  
Hypobaric Chamber

The aim of this study was to examine the effect of reduced O2 tension on the glycosylation of transferrin. Rats were placed in a hypobaric chamber (380 mmHg) that corresponded to an altitude of 5486 m above sea level for 21 days. The animals responded with marked increases in hematocrit (from 44 to 76%) and cardiac weight, and with reductions in the concentration of plasma transferrin averaging 15%. Analyses of their plasma transferrin by serial anion-exchange and lectin affinity chromatography revealed no changes in the extent of glycan branching. However, there was a moderate rise in the proportion of fucosylated transferrin molecules (fucosylation index) and a slight decrease in the transferrin fraction bearing a tetrasialylated biantennary glycan. The fucosylation index correlated positively with plasma transferrin concentrations in the test animals, but not in the controls. In contradistinction to the situation with transferrin, hypoxic rats exhibited a reduced fucosylation index of immunoglobulin G.Key words: fucosylation index, hypoxia, immunoglobulin G, lectin affinity chromatography, transferrin.

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