Passive hemagglutination reaction using formalinized sheep erythrocytes treated with tannic acid and coated with exotoxin of Pseudomonas aeruginosa.

Passive hemagglutination (PHA) tests using fixed sheep erythrocytes coated with exotoxin of Pseudomonas aeruginosa were devised for estimating antibodies of the exotoxin. No serological cross-reactivity among exotoxin OEP, protease and elastase of P. aeruginosa was foud by the PHA tests. The exotoxin PHA reaction was more sensitive than the neutralizing reaction of skin necrotizing activity of exotoxin by guinea pigs. Thirteen out of 40 sera of patients with P. aeruginosa infections showed PHA titers from 40 to 1,280, while those of 20 healthy human sera were under 40.     

Age dependency of ABO histo-blood group antibodies: reexamination of an old dogma

Current textbooks for transfusion medicine state that anti-A and/or anti-B (anti-A/B) agglutination titers–and thus the respective antibody concentrations–reach their maximum in individuals 5 to 10 years old and then gradually decline with the increasing age of the individual. This statement is largely based on a study by Thomsen and Kettel that dates to 1929. In the present article, ABO antibodies in sera of 175 healthy persons aged 61 to 97 years, as well as sera of 170 newborn infants and children aged 0 to 17 years, were analyzed. Microhemagglutination tests were performed with all sera and complemented by ABO enzyme-linked immunosorbent assays to measure the immunoglobulin class (IgM, IgG, and IgA) of the anti-A/B. As in a previous study using sera of persons aged 20 to 67 years, individual differences exceeded age-related changes for all variables. Median values of IgG and IgA anti-A/B were elevated in elderly persons of blood group O, whereas no significant changes were observed in other variables. In particular, the decrease in agglutination titers with the increasing age of the individuals was far less pronounced than previously described; even in sera of persons aged 90 to 97 years, median agglutination titers of 128 were found. Results in the sera of children confirm previously reported data that agglutination titers and IgM anti-A/B reached adult levels at the age of 5 to 10 years.     

Antibodies to peptidoglycan in the sera from population surveys.

A recently described latex agglutination test was used to determine peptidoglycan antibody titers in sera from healthy human subjects and in sera from patients with a history of streptococcal infections or rheumatoid arthritis. Using latex particles coated with group A streptococcal peptidoglycan 32.8% of the sera from 961 healthy donors reacted positively with titers ranging from 1 : 5 to 1 : 320. Peptidoglycan antibodies were more frequently present in the younger population (45.1% in the 20-29 years old) and considerably decreased in advanced age (15.7% in the 70 years or older). Sera from 82 patients with elevated ASO-titers showed detectable peptidoglycan antibody levels in 40.2%; a statistically significant correlation between ASO and peptidoglycan antibody titers could not be substantiated. Sera from 25 patients with rheumatoid arthritis gave a high incidence (56-92%) of positive results. However there was evidence that this may be due to the action of rheumatoid factor present in such sera.     

Human antibodies to bacterial superantigens and their ability to inhibit T-cell activation and lethality

Bacterial superantigens (BSAgs) cause massive stimulation of the immune system and are associated with various pathologies and diseases. To address the role of antibodies in protection against BSAgs, we screened the sera of 29 human volunteers for antibodies to the SAgs staphylococcal enterotoxin A (SEA), SEB, SEC1, and toxic shock syndrome toxin 1 (TSST-1). Although all volunteers had detectable levels of antibodies against SEB and SEC1, many (9 out of 29 volunteers) lacked detectable antibody to SEA or had minimal titers. Antibody titers to TSST-1 were well below those to SEB and SEC1, and three volunteers lacked detectable antibody to this BSAg. In addition, pooled immunoglobulin preparations obtained from different companies had antibody titers against SEs and TSST-1. There was a good correlation between antibody titers and inhibition of superantigenic effects of these toxins. Transfer of SEB-specific antibodies, obtained from pooled sera, suppressed in vitro T-cell proliferation and totally protected mice against SEB. These data suggest that the inhibitory activity of human sera was specific to antibodies directed against the toxins. Thus, it may be possible to counteract with specific antibodies BSAg-associated pathologies caused by stimulation of the immune system.     

STUDIES IN THE RELATION OF THE HEMOLYTIC STREPTOCOCCUS TO RHEUMATIC FEVER : III. COMPLEMENT FIXATION VERSUS STREPTOCOCCAL NUCLEOPROTEINS WITH THE SERA OF PATIENTS WITH RHEUMATIC FEVER AND OTHERS

Complement-fixing antibodies to the cytoplasmic particles (CP) and to the S fraction of streptococcal nucleoproteins are present in normal human sera, the range of concentrations varying among the age groups. The titer of these antibodies rises between the first half-week and the 3rd week of scarlet fever, in more than 80 per cent of the cases. The titers then remain elevated for at least 4 months. In children, 91 per cent of the normal sera examined showed anti-CP titers up to 32; 87 per cent of sera in active rheumatic disease had titers above this level. Corresponding data with S fell in the same range of percentage distribution. Anti-CP and anti-S titers remained elevated long after the rheumatic process had reached quiescence. No correlation of serologic titer with the degree of clinical activity was found in the case of either antibody.     

Incidence of hepatitis A virus infection in children in Taipei, Taiwan

To understand the prevalence and incidence of hepatitis A virus (HAV) infection in Chinese children in Taiwan, we determined the age-specific prevalence of hepatitis A antibodies (anti-HAV) in 823 children, ranging from birth (cord blood) to 19 years of age. The frequency of anti-HAV rose with increasing age with three different slopes, probably reflecting different age-specific incidences: lowest under 4 years of age, intermediate between 4 and 10 years, and highest above 10 years. We obtained follow-up specimens on 618 of the preschool children under 6 years of age. 11 (1.9%) of the 573 without antibodies had seroconversions after an average of 1.9 years of follow-up. The annual incidence was 1.0% and increased with advancing age of the children after infancy. None of the 11 seroconversions had clinical hepatitis. Among the 28 children 1-24 months of age who had antibodies, only 1 was positive on follow-up, reflecting loss of passively acquired maternal antibody in most children.     

Developmental Patterns of ABO Isoagglutinins in Normal Children Correlated with the Effects of Age, Sex, and Maternal Isoagglutinins

The developmental patterns of ABO saline isoagglutinins were determined in 272 children between birth and 16 years of age. The frequency of saline isoagglutinins was significantly higher in group O-O maternal-cord pairs compared to group A-O paired sera. The anti-A and anti-B titers increased gradually from 3 to 12 months: 30 per cent of group O and B children attained adult median titers of isoagglutinin, whereas only 4 per cent of group A children acquired adult anti-B titers. This slow development of anti-B in group A children persisted through the second year. Maternal isoagglutinins may exert a suppressive influence on the development of specific isoagglutinins in the first year of life.     

Seroprevalence of IgG antibodies to pertussis toxin in the Slovene population

BACKGROUND: The use of pertussis vaccines has reduced the morbidity and mortality of whooping cough. Immunity following the natural disease or vaccination is not life-long and reinfections causing an increase of pertussis antibodies can occur. In this study, the distribution of IgG antibodies to pertussis toxin (anti-PT IgG) among different age groups in Slovenia was determined. METHODS: The seroprevalence of anti-PT IgG antibodies to Bordetella pertussis was investigated in 3418 persons (49.1% males). The population under study was stratified into 27 age groups. The serological results were assigned to five groups, according to their titer levels. The geometric mean titers (GMT) were calculated. RESULTS: In 11.5% sera tested, no IgG antibodies to pertussis toxin were detected. High titers (> or =125 U/ml) were confirmed in 2.3% sera. There were no statistically significant differences between age groups in the proportion of antibody levels. Pre-school children from three to five years of age had the lowest anti-PT IgG GMTs (9.6-10.7 U/ml). Vaccinated children (aged from one to two years) and adolescents from 17-18 years of age had the highest GMTs (>20 U/ml). GMTs were not statistically significantly different between males and females. CONCLUSIONS: The study demonstrated an early decline of anti-PT IgG after vaccination. According to the serological profile, school-age children and adolescents have the highest rate of infection. The large proportion of seropositive adults indicates that reinfection with B. pertussis is relatively common.     

Natural autoantibodies against Tamm-Horsfall glycoprotein in normal individuals in relation to age and in adult patients with kidney diseases

IgM and IgG natural antibodies to Tamm-Horsfall glycoprotein (THP) were found in serum samples of all healthy individuals tested by the ELISA technique. The IgM anti-THP antibody level was higher in the group 1-20 years old than the IgG anti-THP. The IgG anti-THP rose with increase in age (greater than 21 years old groups) and then the IgG and IgM anti-THP activity over aging remained constant. The natural anti-THP antibodies possess a lower degree of specificity and/or avidity than induced antibodies. The antibody titers against THP determined in 61 adult patients with chronic kidney diseases was significantly lower than that in adult controls. This low level of naturally occurring THP antibodies appears to be a general phenomenon. In these patients, diminished antibody levels appeared against a panel of self (collagen, fibronectin, THP) and non self (bovine gamma globulin (BGG), ovalbumin (OVA)) antigens as compared with normal controls. The low levels of these antibodies are not associated with a concomitant drop of IgG and IgM in their sera.     

Serological response to plasmid-encoded antigens in children and adults with shigellosis

The immunological response to plasmid-encoded antigens of virulent Shigella was determined in Thai children less than 4 yr of age and in Thai adults by immunoblot analysis and ELISA. Forty-two percent (8/19) of Thai children and 4% (1/22) of Thai adults with shigellosis developed a greater than or equal to 4-fold rise in IgG antibody titer to water-extracted antigens of Shigella flexneri M90T by ELISA (p = 0.006). Two children and one lactating mother with shigellosis developed a 4-fold rise in serum IgA antibody titers to water-extracted antigens of M90T. The results of the ELISA were confirmed by immunoblot analysis in all of the 41 paired sera examined. Five patients developed IgA, and four developed IgM, antibodies as detected by immunoblot analysis, that were not detected by ELISA. The reciprocal log2 geometric mean titers of antibodies to plasmid-encoded antigens in acute sera was higher in Thai adults than Thai children: IgG 7,265 versus 1,659; IgM 879 versus 480; and IgA 662 versus 60 (p less than 0.001). Thai adults had high titers of antibodies to plasmid-encoded antigens in their acute sera, but were susceptible to Shigella infections, although they were historically less susceptible than Thai children.     

Direct evidence that decreased serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in sickle cell disease is related to antibody deficiency.

Two approaches were used to demonstrate that reduction in serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in children with sickle cell disease is related to a deficiency of antibodies to pneumococcal capsular polysaccharide. First, opsonization of S. pneumoniae mediated by the alternative pathway in patients' sera was restored to normal by addition of the purified IgG or IgM fraction of goat antiserum to capsular polysaccharide of the homologous serotype. Secondly, IgG antibody titers to capsular polysaccharide in patients' sera correlated significantly with alternative pathway-mediated opsonization; the correlation between titers of IgM anticapsular antibodies and opsonization approached statistical significance. The sum of the IgG and IgM anticapsular antibody titers correlated most significantly with opsonization. Our results suggest that reduction in alternative pathway-mediated opsonization in sera from children with sickle cell disease is related to low levels of both IgG and IgM anticapsular antibodies.     

Occurrence of Epstein-Barr virus deoxyribonuclease enzyme activity-neutralizing antibodies. An index of Epstein-Barr virus disease

The occurrence of Epstein-Barr virus (EBV) specific DNase antibodies was measured in the sera of 400 patients. Three hundred sera were positive (greater than or equal to 20) for early antigen diffuse component (EA-D) antibodies, as measured by indirect immunofluorescence (IF). One hundred sera were EA-D antibody-negative but had IF IgG titers (greater than 40) to the viral capsid antigen (VCA). Twenty-nine of the anti-EA-D-positive sera, and 14 of the anti-EA-D-negative sera showed specific inhibition of EBV DNase. The mean age of positive male patients (39 years) for DNase antibodies was significantly higher (p less than 0.05) than the mean age of positive females (27 years). Thirteen of the 40 patients (29.5%) with acquired immunodeficiency syndrome (AIDS) had EBV DNase-neutralizing antibodies. No correlation between the level of anti-DNase antibodies and the antibody titer to EA-D or VCA was observed. These results support the notion that the EBV DNase antibody assay measures an independent index reflecting factual EBV disease.     

Assay for antibodies to group C and G streptococcal carbohydrate by enzyme-linked immunosorbent assay

An enzyme-linked immunosorbent technique was established for the assay of serum antibodies to the group C and G streptococcal group-specific carbohydrates. The antigens consisted of formamide-extracted purified polysaccharides conjugated to poly-L-lysine. By use of hyperimmune rabbit antisera to the streptococcal group-specific polysaccharides A, C, and G, a high degree of specificity was encountered for each of the antigens tested. Antibody titers to these antigens were then measured in sera of 100 normal individuals varying in age from newborn to 20 years. The mean titer of these antibodies increased significantly between the ages of 5 and 15 years and leveled off thereafter. Assay of antibodies to the group A, C, and G carbohydrates on sera of patients with antecedent group A streptococcal infections or rheumatic fever and their matched normal controls revealed significantly elevated titers for the antibody to streptococcal group A carbohydrate only in the sera of these patients. These results support the specificity of these tests and suggest their potential usefulness for providing evidence for infection by the various streptococcal serogroups in humans.     

Antibiodies of the IgG, IgM, and IgA classes in newborn and adult sera reactive with gram-negative bacteria

Umbilical cord serum and adult serum antibodies reactive with heat-stable somatic antigens of Gram-negative bacteria (Neisseria gonorrhoeae, Escherichia coli, and Salmonella typhosa) were assayed by using an indirect fluorescent antibody test. Reactive IgG, IgM, and IgA antibodies were identified by using fluoresceinconjugated antisera specific for these immunoglobulin classes.IgG antibody titers in cord serum approximated those found in the corresponding maternal sera. IgM and IgA antibodies were present in adult sera but were not demonstrable or were present only in small amounts in cord sera. The presence of IgG and IgM antibodies reactive with Gram-negative bacteria was confirmed by the testing of purified 7S and 19S fractions. In addition, both IgG and IgM reactivities were inhibited by the prior incubation of serum with purified specific lipopolysaccharide preparations.The ubiquity and magnitude of these natural IgG antibodies in the sera of both adults and neonates have apparently eluded detection in previous studies. The use of bactericidal and agglutination tests, which are apparently more sensitive to the presence of IgM than to IgG antibodies, may account for the failure of previous studies to detect adult and cord IgG antibodies reactive with somatic antigens of Gram-negative bacteria. The presence of these IgG antibodies may be correlated with the resistance to infection demonstrated by most newborns as they are challenged by the septic extrauterine environment.     

THE PLACENTAL TRANSMISSION OF ANTIBODIES IN THE SKIN SENSITIVE TYPE OF HUMAN ALLERGY

1. Quantitative studies of the skin-sensitizing antibodies, blocking antibodies, and hemagglutinins in sera of allergic human beings have been made. 2. A comparison of 12 maternal and the 12 corresponding cord sera by the method of passive transfer showed the human placenta to be impermeable to skin-sensitizing antibodies. 3. Direct skin tests and passive transfer studies of 6 infants at the ages of 3 to 6 months showed negative reactions to the antigens to which their mothers were sensitive. 4. The blocking antibody present in the sera of hay fever patients after treatment with pollen extract injections was also demonstrated in the cord sera. The apparent placental transmission of this antibody gave further evidence that it was distinct from the skin-sensitizing antibody. Infant sera obtained at the ages of 3 to 6 months showed no evidence of this immune antibody. 5. The cord sera from 4 of these cases were shown to contain the same isoagglutinins as the maternal sera, showing that the placentas were permeable to these antibodies. The mothers and their offspring reacted alike to Schick testing. 6. Typhoid agglutinins were demonstrated in maternal and cord sera of an adult who previously received injections of triple typhoid vaccine, whereas the serum of the corresponding infant at the age of 3 months failed to show agglutinins.     

Clinical symptoms and IgE responses to common food proteins and inhalants in the first 7 years of life

A group of eighty-six children followed from birth to 4 years of age and previously reported was now re-investigated at the age of 7 years. The prevalence of atopy/allergy was 15%. All of the children with current atopy/allergy had had previous manifestations during their first 4 years of life. No child was allergic to milk at the age of 7 years and only two of the six children with a previous allergy to eggs retained their allergy. No other children had developed allergies to milk or eggs. Only one of the eight children with an elevated level of IgE antibodies to egg white (RAST class 1 or more) during infancy still had increased concentrations of such antibodies. No child had developed an elevated level of IgE antibodies to egg white or milk after the first year of life. Clinical allergies to inhalants had increased from 1% at 4 years of age to 7% at 7 years. Children with elevated levels of IgE antibodies to inhalants had increased from 7% at 4 years of age to 10% at 7 years. The majority of them had had increased levels of IgE antibodies to egg white during infancy. The specificity of an elevated level of cord blood IgE, i.e. above 0.9 kU/l for predicting atopy/allergy during the first 7 years of life and for current atopy/allergy at 7 years of age were both 95%. The corresponding figures for presence of elevated levels of IgE antibodies to egg white (positive RAST) during infancy were 98 and 97%, respectively. The sensitivity of the cord blood IgE predictor was 14 and 17%, respectively and for a positive RAST to egg white during infancy 32 and 50%, respectively.     

IgE antibody production to exoenzymes and common antigen (OEP) of Pseudomonas aeruginosa in mice.

IgE antibody production to exoenzymes and common antigen (OEP) of P. aeruginosa was studied in mice that were injected with the antigens incorporated into water-in-oil-in-water (w/o/w) emulsion or Al(OH)3 gel. OEP and protease toxoid (PT) elicited IgE antibody response but elastase toxoid (ET) did not. Capacity of the OEP to produce IgE antibody was reduced remarkably by it's protease treatment, which suggested that the capacity lies in the protein portion of OEP. The w/o/w emulsion was less effective than Al(OH)3 gel in adjuvanticity to elicit IgE antibody response, but the emulsion enhanced the IgM and/or IgG antibody response to PT and maintained a constant level for a long period. These findings may suggest that IgE antibody response to some components of P. aeruginosa could be induced in man. High serum level of IgE was observed in some cases of cystic fibrosis caused by P. aeruginosa infection, although the IgE antibody activity has not yet been determined.     

Protective activity of antibodies to exotoxin A and lipopolysaccharide at the onset of Pseudomonas aeruginosa septicemia in man.

Serum antibodies to exotoxin A and type-specific lipopolysaccharide were measured by passive hemagglutination in 52 patients with Pseudomonas aeruginosa septicemia. Their comparative protective activities were evaluated by relating the titers of each at the onset of bacteremia to subsequent outcome. High acute serum antitoxin and antilipopolysaccharide titers (log2 reciprocal mean titers greater than 5) were associated with survival (76% of 17 with high vs. 46% of 24 with low antitoxin titers, P = 0.05; 85% of 13 with high vs. 48% of 29 with low antilipopolysaccharide titers, P = 0.03). In contrast, neither antibody titer was significantly associated (P less than or equal to 0.05) with patients' age or sex, severity of underlying disease, presence of leukopenia, steroid or immunosuppressive therapy. Despite a correlation between acute titers of the two antibodies (r = 0.33, P = 0.06), they appeared to protect independently and additively. Whereas 75% of 8 patients with high antitoxin titers and only 38% of 16 with low titers survived with low antilipopolysaccharide titers (P = 0.10), 100% (6/6), 73% (8/11), and 38% (6/16) survived, respectively, when both, one, or neither antibody was present in high titer (P = 0.01). Furthermore, the association between high acute serum antitoxin titers and survival was more pronounced in patients with rapidly fatal underlying disease (P = 0.06) and leukopenia (P = 0.12) than in more favorable prognostic and immune categories. These data indicate that serum antibodies to exotoxin A and lipopolysaccharide are found in most patients with P. aeruginosa septicemia and both are protective. Both antibodies may have therapeutic or prophylactic potential, whereas serum antiexotoxin A antibodies may be particularly beneficial in compromised hosts.     

Immunization of Humans with Polyribophosphate, the Capsular Antigen of Hemophilus influenzae, Type b

In human volunteers, single injections of purified polyribophosphate elicited antibodies detectable by passive hemagglutination and by serum bactericidal and opsonizing activities against viable Hemophilus influenzae, type b. All three activities rose by 2 wk to maximal levels, at which they remained for at least 6 months. Doses of 1 mug elicited antibody responses in nearly all recipients; higher doses of the antigen, however, produced larger increases in titer. Booster doses of 1 mug given at 6 months did not further increase the antibody titers. A tuberculin-like response was often observed at the site of injections given intradermally.     

Anti-skeletal muscle and anti-acetylcholine receptor antibodies in patients with thymoma without myasthenia gravis: relation to the onset of myasthenia gravis.

We measured the anti-skeletal muscle (SM) antibody titers in sera from 46 patients with thymoma but without Myasthenia gravis (MG) in order to determine whether the presence of anti-SM antibody is linked to the combination of thymoma-MG, or to thymoma alone. We detected anti-SM antibodies in 18 of these sera, of which 15 had concomitantly elevated titers of anti-AChR antibodies. Moreover, 9 of whom had experienced the onset of MG after surgery. In contrast, no patient without elevations in both antibodies developed MG during the followup. We conclude that the presence of anti-SM antibodies is linked strongly with thymoma associated with MG, but not with thymoma alone.