scholarly journals Demonstration of a natural antigalactosyl IgG antibody on thalassemic red blood cells

Blood ◽  
1983 ◽  
Vol 61 (6) ◽  
pp. 1258-1264 ◽  
Author(s):  
U Galili ◽  
A Korkesh ◽  
I Kahane ◽  
EA Rachmilewitz
Keyword(s):  
Sialic Acid ◽  
Myeloid Cell ◽  
Reticuloendothelial System ◽  
Igg Antibodies ◽  
Igg Antibody ◽  
High Affinity ◽  
Rbc Membrane ◽  
Antiglobulin Test ◽  
Normal Human ◽  
Galactosyl Residues

A modified antiglobulin test, based on the high affinity between the Fc portion of the red blood cell (RBC) bound IgG and the Fc receptor on the myeloid cell K-562, was utilized for demonstration of immunoglobulins (Ig) on thalassemic RBC. Ig was found on the RBC of 73 out of 80 patients with thalassemia. The immunoglobulins on the thalassemic RBC belonged to the IgG subclass and were autoreactive. Elution studies utilizing various carbohydrates, or by thermal stripping, indicated that at least part of the IgG molecules found on the thalassemic RBC were specifically reactive with terminal galactosyl residues on the RBC membrane. IgG antibodies with similar reactivity were also demonstrated in normal human serum. These natural antigalactosyl IgG antibodies from normal sera could bind to IgG- depleted thalassemic RBC. Thalassemic RBC and normal senescent RBC were previously found to contain reduced amounts of membrane sialic acid (SA). It is suggested that the antigalactosyl IgG antibodies interact with newly exposed galactosyl residues underlying the sialic acid units. Such interaction may lead to the shortened lifespan of thalassemic RBC and may result in sequestration of senescent normal RBC by the reticuloendothelial system.

scholarly journals Demonstration of a natural antigalactosyl IgG antibody on thalassemic red blood cells

Blood ◽  
1983 ◽  
Vol 61 (6) ◽  
pp. 1258-1264 ◽  
Author(s):  
U Galili ◽  
A Korkesh ◽  
I Kahane ◽  
EA Rachmilewitz
Keyword(s):  
Sialic Acid ◽  
Myeloid Cell ◽  
Reticuloendothelial System ◽  
Igg Antibodies ◽  
Igg Antibody ◽  
High Affinity ◽  
Rbc Membrane ◽  
Antiglobulin Test ◽  
Normal Human ◽  
Galactosyl Residues

Abstract A modified antiglobulin test, based on the high affinity between the Fc portion of the red blood cell (RBC) bound IgG and the Fc receptor on the myeloid cell K-562, was utilized for demonstration of immunoglobulins (Ig) on thalassemic RBC. Ig was found on the RBC of 73 out of 80 patients with thalassemia. The immunoglobulins on the thalassemic RBC belonged to the IgG subclass and were autoreactive. Elution studies utilizing various carbohydrates, or by thermal stripping, indicated that at least part of the IgG molecules found on the thalassemic RBC were specifically reactive with terminal galactosyl residues on the RBC membrane. IgG antibodies with similar reactivity were also demonstrated in normal human serum. These natural antigalactosyl IgG antibodies from normal sera could bind to IgG- depleted thalassemic RBC. Thalassemic RBC and normal senescent RBC were previously found to contain reduced amounts of membrane sialic acid (SA). It is suggested that the antigalactosyl IgG antibodies interact with newly exposed galactosyl residues underlying the sialic acid units. Such interaction may lead to the shortened lifespan of thalassemic RBC and may result in sequestration of senescent normal RBC by the reticuloendothelial system.

Thrombocytopenia after second exposure to abciximab is caused by antibodies that recognize abciximab-coated platelets

Blood ◽  
2002 ◽  
Vol 99 (6) ◽  
pp. 2054-2059 ◽  
Author(s):  
Brian R. Curtis ◽  
Julia Swyers ◽  
Ajit Divgi ◽  
Janice G. McFarland ◽  
Richard H. Aster
Keyword(s):  
Healthy Subjects ◽  
Igg Antibodies ◽  
Igg Antibody ◽  
Fab Fragment ◽  
Fab Fragments ◽  
Fibrinogen Receptor ◽  
Patients At Risk ◽  
Life Threatening ◽  
Normal Human ◽  
Normal Antibodies

Abstract Thrombocytopenia, often severe, occurs in 1% to 2% of patients given the fibrinogen receptor antagonist abciximab, a chimeric Fab fragment containing murine specificity-determining and human framework sequences. The cause of this complication has not yet been defined. Studies of 9 patients who developed profound thrombocytopenia (platelets <10 × 109/L [10 000/μL]) within a few hours of being given abciximab a second time showed that each had a strong immunoglobulin G (IgG) antibody that recognized platelets sensitized with abciximab. Five patients also had IgM antibodies. IgG antibodies reactive with abciximab-coated platelets were also found in 77 (74%) of 104 healthy subjects. However, the patient antibodies could be distinguished from “normal” ones in 2 ways: (1) only the patient antibodies reacted preferentially with platelets sensitized with the intact monoclonal antibody 7E3 from which the murine sequences in abciximab are derived; and (2) the “normal” antibodies could be inhibited by Fab fragments derived from normal human IgG, whereas the patient antibodies were relatively resistant to this treatment. The findings suggest that antibodies from the patients are specific for murine sequences in abciximab and are capable of causing life-threatening thrombocytopenia upon injection of this drug. The antibodies commonly found in healthy subjects are specific for the papain cleavage site of any Fab fragments and, although they react with abciximab-coated platelets, appear not to cause significant thrombocytopenia. It may be possible to identify patients at risk for developing thrombocytopenia if given abciximab by screening for antibodies that recognize 7E3-coated platelets.

scholarly journals Serologic profile of alphamethyldopa-induced hemolytic anemia: correlation between cell-bound IgM and hemolysis

Blood ◽  
1982 ◽  
Vol 59 (1) ◽  
pp. 61-68
Author(s):  
P Lalezari ◽  
JE Louie ◽  
N Fadlallah
Keyword(s):  
Hemolytic Anemia ◽  
Complement Activation ◽  
Hemolytic Activity ◽  
Igg Antibodies ◽  
Cold Agglutinins ◽  
High Affinity ◽  
Igm Antibodies ◽  
Antiglobulin Test ◽  
Complement C1q ◽  
Classic Pathway

Erythrocyte-bound immunoglobulins have been characterized by a PVP- potentiated antiglobulin test in 11 patients who had developed antibodies after treatment with alpha-methyldopa. Serologic profiles were recognized that could distinguish between the hemolyzing and nonhemolyzing patients: IgM antibodies together with the first component of complement (C1q) were demonstrated on erythrocytes of all eight hemolyzing patients. By contrast, these immunoproteins were absent from the cells of nonhemolyzing patients and became undetectable when the hemolyzing patients recovered. IgG and its subclasses were variably present on erythrocytes of all patients regardless of hemolytic activity. Eluates prepared from erythrocytes of the hemolyzing patients were shown to contain both IgG and IgM, and fixes C1q, C3, and C4. Eluates from the nonhemolyzing patients contained only IgG. The IgM antibodies differed from the commonly occurring cold agglutinins in that they were warm-reactive and were mainly concentrated on the patients' cells rather than being free in the serum. Because of their nonagglutinating property, it is suggested that they are monomeric IgM. It is concluded that the high affinity, warm- reactive IgM and not the IgG antibodies are primarily responsible for clinically manifest anemia in patients receiving alphamethyldopa and that the hemolytic activity is probably mediated by the classic pathway of complement activation.

scholarly journals Serologic profile of alphamethyldopa-induced hemolytic anemia: correlation between cell-bound IgM and hemolysis

Blood ◽  
1982 ◽  
Vol 59 (1) ◽  
pp. 61-68 ◽  
Author(s):  
P Lalezari ◽  
JE Louie ◽  
N Fadlallah
Keyword(s):  
Hemolytic Anemia ◽  
Complement Activation ◽  
Hemolytic Activity ◽  
Igg Antibodies ◽  
Cold Agglutinins ◽  
High Affinity ◽  
Igm Antibodies ◽  
Antiglobulin Test ◽  
Complement C1q ◽  
Classic Pathway

Abstract Erythrocyte-bound immunoglobulins have been characterized by a PVP- potentiated antiglobulin test in 11 patients who had developed antibodies after treatment with alpha-methyldopa. Serologic profiles were recognized that could distinguish between the hemolyzing and nonhemolyzing patients: IgM antibodies together with the first component of complement (C1q) were demonstrated on erythrocytes of all eight hemolyzing patients. By contrast, these immunoproteins were absent from the cells of nonhemolyzing patients and became undetectable when the hemolyzing patients recovered. IgG and its subclasses were variably present on erythrocytes of all patients regardless of hemolytic activity. Eluates prepared from erythrocytes of the hemolyzing patients were shown to contain both IgG and IgM, and fixes C1q, C3, and C4. Eluates from the nonhemolyzing patients contained only IgG. The IgM antibodies differed from the commonly occurring cold agglutinins in that they were warm-reactive and were mainly concentrated on the patients' cells rather than being free in the serum. Because of their nonagglutinating property, it is suggested that they are monomeric IgM. It is concluded that the high affinity, warm- reactive IgM and not the IgG antibodies are primarily responsible for clinically manifest anemia in patients receiving alphamethyldopa and that the hemolytic activity is probably mediated by the classic pathway of complement activation.

scholarly journals Red blood cell associated IgG in normal and pathologic states

Blood ◽  
1980 ◽  
Vol 55 (1) ◽  
pp. 48-54 ◽  
Author(s):  
IO Szymanski ◽  
PR Odgren ◽  
NL Fortier ◽  
LM Snyder
Keyword(s):  
Blood Cell ◽  
Hemolytic Anemia ◽  
Blood Cells ◽  
Hereditary Spherocytosis ◽  
Reticulocyte Count ◽  
Igg Antibody ◽  
Rbc Membrane ◽  
Antiglobulin Test ◽  
Membrane Bound

We studied the anti-IgG-induced agglutination of both normal and abnormal red blood cells (RBC) using a sensitive, automated antiglobulin test. Normal RBC agglutinated strongly with anti-IgG antibody, indicating that IgG was present on the erythrocyte membrane. Young RBC, recovered by centrifugation from a normal RBC population, agglutinated with anti-IgG less than the old cells, suggesting that immunoglobulin G accumulated gradually on the RBC membrane in vivo. The degree of anti-IgG-induced RBC agglutination correlated negatively with the reticulocyte count and positively with the concentration of plasma IgG. RBC from patients with hypogammaglobulinemia appeared to have a low subnormal quantity of membrane-bound IgG, whereas the reverse was the case in hypergammaglobulinemia. During hemolytic episodes, RBC of patients with hereditary spherocytosis agglutinated poorly with anti- IgG, apparently due to predominance of young RBC. RBC of patients with nonspherocytic. Coombs-negative, nonimmune hemolytic anemia usually also agglutinated poorly with anti-IgG. However, in some cases of active hemolytic anemia, decreased agglutination with anti-IgG was not observed, suggesting that these young RBC had increased amounts of membrane-bound IgG.

scholarly journals Red blood cell associated IgG in normal and pathologic states

Blood ◽  
1980 ◽  
Vol 55 (1) ◽  
pp. 48-54 ◽  
Author(s):  
IO Szymanski ◽  
PR Odgren ◽  
NL Fortier ◽  
LM Snyder
Keyword(s):  
Blood Cell ◽  
Hemolytic Anemia ◽  
Blood Cells ◽  
Hereditary Spherocytosis ◽  
Reticulocyte Count ◽  
Igg Antibody ◽  
Rbc Membrane ◽  
Antiglobulin Test ◽  
Membrane Bound

Abstract We studied the anti-IgG-induced agglutination of both normal and abnormal red blood cells (RBC) using a sensitive, automated antiglobulin test. Normal RBC agglutinated strongly with anti-IgG antibody, indicating that IgG was present on the erythrocyte membrane. Young RBC, recovered by centrifugation from a normal RBC population, agglutinated with anti-IgG less than the old cells, suggesting that immunoglobulin G accumulated gradually on the RBC membrane in vivo. The degree of anti-IgG-induced RBC agglutination correlated negatively with the reticulocyte count and positively with the concentration of plasma IgG. RBC from patients with hypogammaglobulinemia appeared to have a low subnormal quantity of membrane-bound IgG, whereas the reverse was the case in hypergammaglobulinemia. During hemolytic episodes, RBC of patients with hereditary spherocytosis agglutinated poorly with anti- IgG, apparently due to predominance of young RBC. RBC of patients with nonspherocytic. Coombs-negative, nonimmune hemolytic anemia usually also agglutinated poorly with anti-IgG. However, in some cases of active hemolytic anemia, decreased agglutination with anti-IgG was not observed, suggesting that these young RBC had increased amounts of membrane-bound IgG.

Seroprevalence of anti-SARS-CoV-2 IgG antibodies in hospitalized patients at a tertiary referral center in North India (Preprint)

2020 ◽  
Author(s):  
Dr. Animesh Ray ◽  
Dr. Komal Singh ◽  
Souvick Chattopadhyay ◽  
Farha Mehdi ◽  
Dr. Gaurav Batra ◽  
...  
Keyword(s):  
Tertiary Care ◽  
Age Groups ◽  
Hospitalized Patients ◽  
North India ◽  
P Value ◽  
Care Hospital ◽  
Igg Antibodies ◽  
Igg Antibody ◽  
Increased Risk ◽  
Significant Difference

BACKGROUND Seroprevalence of IgG antibodies against SARS-CoV-2 is an important tool to estimate the true extent of infection in a population. However, seroprevalence studies have been scarce in South East Asia including India, which, as of now, carries the third largest burden of confirmed cases in the world. The present study aimed to estimate the seroprevalence of anti-SARS-CoV-2 IgG antibody among hospitalized patients at one of the largest government hospital in India OBJECTIVE The primary objective of this study is to estimate the seroprevalence of SARS-CoV-2 antibody among patients admitted to the Medicine ward and ICU METHODS This cross-sectional study, conducted at a tertiary care hospital in North India, recruited consecutive patients who were negative for SARS-CoV-2 by RT-PCR or CB-NAAT. Anti-SARS-CoV-2 IgG antibody levels targeting recombinant spike receptor-binding domain (RBD) protein of SARS CoV-2 were estimated in serum sample by the ELISA method RESULTS A total of 212 hospitalized patients were recruited in the study with mean age (±SD) of 41.2 (±15.4) years and 55% male population. Positive serology against SARS CoV-2 was detected in 19.8%patients(95% CI 14.7-25.8). Residency in Delhi conferred a higher frequency of seropositivity 26.5% (95% CI 19.3-34.7) as compared to that of other states 8% (95% CI 3.0-16.4) with p-value 0.001. No particular age groups or socio-economic strata showed a higher proportion of seropositivity CONCLUSIONS Around, one-fifth of hospitalized patients, who were not diagnosed with COVID-19 before, demonstrated seropositivity against SARS-CoV-2. While there was no significant difference in the different age groups and socio-economic classes; residence in Delhi was associated with increased risk (relative risk of 3.62, 95% CI 1.59-8.21)

scholarly journals Heterocyclic boronic acids display sialic acid selective binding in a hypoxic tumor relevant acidic environment

2017 ◽  
Vol 8 (9) ◽  
pp. 6165-6170 ◽  
Author(s):  
A. Matsumoto ◽  
A. J. Stephenson-Brown ◽  
T. Khan ◽  
T. Miyazawa ◽  
H. Cabral ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Boronic Acids ◽  
Sialic Acids ◽  
Strong Interactions ◽  
Acidic Ph ◽  
Acidic Environment ◽  
Selective Binding ◽  
High Affinity ◽  
Ph Conditions ◽  
Hypoxic Tumor

A group of heterocyclic boronic acids demonstrating unusually high affinity and selectivity for sialic acids are described, with strong interactions under the weakly acidic pH conditions associated with a hypoxic tumoral microenvironment.

scholarly journals Immunoglobulin G antibodies directed against protein III block killing of serum-resistant Neisseria gonorrhoeae by immune serum.

1986 ◽  
Vol 164 (5) ◽  
pp. 1735-1748 ◽  
Author(s):  
P A Rice ◽  
H E Vayo ◽  
M R Tam ◽  
M S Blake
Keyword(s):  
Membrane Protein ◽  
Neisseria Gonorrhoeae ◽  
Human Serum ◽  
Outer Membrane ◽  
Outer Membrane Protein ◽  
Immune Serum ◽  
Igg Antibodies ◽  
Porin Protein ◽  
Blocking Activity ◽  
Normal Human

Neisseria gonorrhoeae that resist complement-dependent killing by normal human serum (NHS) are sometimes killed by immune convalescent serum from patients recovering from disseminated gonococcal infection (DGI). In these studies, killing by immune serum was prevented or blocked by IgG isolated from NHS. Purified human IgG antibodies directed against gonococcal protein III, an antigenically conserved outer membrane protein, contained most of the blocking activity in IgG. Antibodies specific for gonococcal porin (protein I), the major outer membrane protein, displayed no blocking function. In separate experiments, immune convalescent DGI serum which did not exhibit bactericidal activity was restored to killing by selective depletion of protein III antibodies by immunoabsorption. These studies indicate that protein III antibodies in normal and immune human serum play a role in serum resistance of N. gonorrhoeae.

Sign in / Sign up

Export Citation Format

Share Document