PubMed Health⌕ Search

Biomedical subjects

L A Hanson

Publications and source records attributed to L A Hanson.

At least 19 recordsLinked to original sources
PubMed1992

Aberrations in titre and avidity of serum IgM and IgG antibodies to microbial and food antigens in IgA deficiency.

The antibody levels and relative avidity of serum IgM and IgG antibodies against E. coli O antigens, poliovirus type 1 and beta-lactoglobulin were determined with enzyme-linked immunosorbent techniques in IgA deficient (IgAd) patients with frequent respiratory tract infections and healthy IgAd individuals. Healthy individuals with normal immunoglobulin levels served as controls. The IgM antibody levels against the bacterial, viral and food antigens and the IgG antibody levels against the bacterial antigens were significantly higher in the IgAd group with recurrent infections than in the group of healthy IgAd individuals. The symptomatic IgAd group had significantly higher levels of the IgG antibodies against the bacterial antigen, also when compared with controls. In contrast the healthy IgAd individuals had the highest avidities of IgM antibodies to the viral and food antigens. The high avidities of antibodies could be a compensatory host defence mechanism in IgAd. These aberrations may appear as a consequence of increased mucosal exposure in IgAd to antigens such as E. coli or beta-lactoglobulin, but presumably not to poliovirus which is only exceptionally present in the milieux. They could also be a result of the previously suggested dysregulation of antibody responses in IgAd.

Antibody Affinity↗
PubMed1992

A comparison of secretory antibodies in breast-fed and formula-fed infants over the first six months of life.

In the present study salivary IgA, anti-Escherichia coli, anti-beta-lactoglobulin and anti-poliovirus type 1 IgA and IgM in serum and saliva were evaluated longitudinally in 13 breast-fed and 14 formula-fed infants over the first six months of life. Salivary IgA was quantified by electroimmunodiffusion; specific IgA and IgM antibodies were determined in serum and saliva by ELISA. Salivary IgA was significantly lower at age one month in breast-fed compared with formula-fed infants but in breast-fed infants salivary IgA increased with age and was significantly higher at six months than at one month. In both groups of infants, at the age of six months, salivary IgA levels were significantly lower than in adult controls. No significant differences in secretory anti-E. coli were observed between the two groups of infants. Salivary anti-poliovirus IgA and IgM antibodies increased transiently only to disappear in most babies at age six months, while anti-beta lactoglobulin IgA and IgM, present in saliva at all ages, showed a wide scatter. No important differences in specific serum IgA or IgM antibodies were observed either between the groups or at different times within the groups.

Age Factors↗
PubMed1992

Presence of non-maternal antibodies in newborns of mothers with antibody deficiencies.

To explain the mechanism for induction and production of specific antibodies found in the newborn already at birth, without previous known exposure to the antigen, we chose a model that presumably excluded the possibility of specific antibodies being transferred from the mother to the fetus. Specific IgG, IgA, and IgM antibodies against Escherichia coli and poliovirus antigens were determined with ELISA in serum, saliva, and amniotic fluid from hypogammaglobulinemic and IgA-deficient mothers as well as in cord serum, saliva, and meconium from their offspring. All the mothers lacked IgA and some also lacked IgM antibodies, which were found in their healthy newborns. The amniotic fluid from a hypogammaglobulinemic mother lacking IgA contained small amounts of IgA antibodies, which were also found in the neonate, suggesting a fetal origin. There was evidence for the presence of antiidiotypic antibodies to poliovirus in the cord sera. We propose that idiotypic and/or antiidiotypic IgG antibodies transferred via the placenta from the mother to the fetus can initiate specific immune responses seen in the newborn. Thus, it may be that transplacental IgG not only passively protects the newborn, but also actively primes the fetus during fetal life via its content of idiotypic and/or antiidiotypic antibodies.

Agammaglobulinemia↗
PubMed1979

[Local immunity].

Explore the source record for details and available documents.

Body Fluids↗
PubMed1979

The secretory IgA system in the neonatal period.

It is still not known when the secretory IgA response, important for defence of the mucous membranes, becomes fully competent in the human infant. The infant is, however, provided with 0.25--0.5 g of secretory IgA/day via the maternal milk. The milk contains secretory IgA antibodies against a wide variety of antigens from microorganisms, including bacteria, viruses and parasites. Many of the antibodies are directed against important virulence factors such as bacterial pili, enterotoxins, capsular polysaccharides and endotoxic lipopolysaccharides. The passive transfer of antibodies through the milk may explain why breast-fed infants are resistant to enteric infections in particular. The antibodies in the milk are often directed against antigens in the mother's milieu and intestine. An entero-mammary gland link, possibly consisting of lymphoid cells homing from the Peyer's patches in the intestine to the mammary gland, has been suggested. A limited selective uptake of oligomeric IgA from serum in exocrine glands, including the mammary glands, has also been indicated. Whichever the mechanism, the antibodies transferred via breast milk are composed to meet the needs of the infant.

Adolescent↗
PubMed1979

Autoantibodies to Tamm-Horsfall protein associated with urinary tract infections in girls.

Girls with various forms of urinary tract infections and a reference material were analyzed for autoantibodies in serum to the Tamm-Horsfall glycoprotein. Such antibodies could be detected in all sera analyzed. In the control subjects cord blood contained very low IgA and IgM anti-TH, which increased significantly up to the age of 8 months. The IgG anti-TH levels in cord blood correlated with maternal levels. After the age of 2 months the IgG anti-TH followed the anti-TH levels of the other immunoglobulin classes. Among the infants aged 2 to 7 months with acute UTI, no anti-TH increases were found. In girls more than one year of age with acute nonobstructive UTI, IgG and IgA anti-TH levels were significantly higher in those with acute pyelonephritis and reflux, with or without parenchymal reduction, than in those with acute pyelonephritis and normal radiologic findings. The latter group had significantly higher levels of IgG and IgA but not IgM anti-TH than did those with acute cystitits. In contrast, girls with renal parenchymal reduction but no signs of infection at the time of testing had significantly depressed anti-TH levels compared to control values.

Adolescent↗
PubMed1979

Immunological aspects of pyelonephritis.

Several virulence factors, such as O and K antigens and capacity to attach to uroepithelial cells, seem to be required for Escheria coli to cause acute pyelonephritis. These factors induce an immune response, however, which can modify the course and clinical expression of the infection. During acute pyelonephritis, autoantibodies to the Tamm-Horsfall protein increase. These antibodies, which probably are evoked by a cross-reaction noted between structures of E. coli LPS and the Tamm-Horsfall protein, may add to the renal tissue engagement in interstitial nephritis caused by bacterial pyelonephritis.

Acute Disease↗
PubMed1979

Localization and therapy of urinary tract infections of childhood.

One hundred four patients with 124 episodes of urinary tract infection were studied. Serum C-reactive protein (CRP) was determined on diagnosis of each patient. Children with a CRP equal to or greater than 30 micrograms/ml (CRP-pos) differed significantly from those with values less than 30 micrograms/ml (CRP-neg) in age, clinical presentation, K type of Escherichia coli causing disease, frequency or radiographic abnormalities, and presence of antibody coating of bacteria in the urinary sediment. E. coli K1 strains caused disease significantly more often in CRP-pos than in CRP-neg patients, and children with K1 infections were younger than those with non-K1 infections. The antibody-coated bacteria test was neither sensitive nor specific for localization of infection in pediatric patients. Determination of K1 antibody concentrations in serum and urine of E. coli K1-infected children provided data supporting the measurement of CRP as one means of localizing urinary tract infections. Patients with CRP-neg infections were treated as successfully with four days of antimicrobial therapy as with ten days.

Acute Disease↗
PubMed1978

Secretory IgA antibodies to enterobacterial virulence antigens: their induction and possible relevance.

1) Milk and salivary s-IgA antibodies are via the homing of IgA producing cells from the Peyer's patches closely connected with antigenic stimuli in the intestine. This explains the presence in human milk of s-IgA antibodies against E. coli O and K antigens, V. cholerae and Shigella O antigens, E. coli and V. cholerae enterotoxins. These secretory antibodies can be induced by intestinal exposure and boosted by parenteral vaccination. 2) Preliminary data suggest that the IgA response in the urinary tract and possibly in the lung may be involved in the homing mechanism as well. 3) The protective role of the milk s-IgA antibodies to enterobacterial virulence antigens is strongly suggested, as is the protection mediated by urinary antibodies against urinary tract infections.

Animals↗
PubMed1978

Asymptomatic bacteriuria in schoolgirls. VIII. Clinical course during a 3-year follow-up.

A 3-year follow-up of 116 schoolgirls with asymptomatic bacteriuria, treated or untreated is reported. It is concluded that bacteria isolated from girls with asymptomatic bacteriuria do not commonly cause symptomatic pyelonephritis and that the risk of developing renal damage as a result of asymptomatic bacteriuria in a schoolgirl with a roentgenographically normal urinary tract seems to be small. It is also suggested that for the majority of these patients therapy is not necessary.

Adolescent↗
PubMed1978

Adhesion to normal human uroepithelial cells of Escherichia coli from children with various forms of urinary tract infection.

The ability to adhere to normal human uroepithelial cells was compared for Escherichia coli strains isolated from the urine of girls with acute pyelonephritis, acute cystitis, or asymptomatic bacteriuria, and from the stools of school children without bacteriuria. Strains from those with acute pyelonephritis had high adhesive ability, whereas strains from those with acute cystitis had intermediate and strains from girls with asymptomatic bacteriuria or from normal feces had low adhesive ability. Strains of serogroup O4K12 had good adherence regardless of origin. E. coli of the eight O groups commonly found in patients with acute pyelonephritis adhered more than did strains of other O groups. Spontaneously agglutinating strains had less adhesive ability than did the O-typable ones.

Acute Disease↗
PubMed1978

Escherichia coli in bacteremia: K and O antigens and serum sensitivity of strains from adults and neonates.

Comparisons of O- and K-antigenic types and serum sensitivity were carried out with 149 strains of Escherichia coli isolated from adults with bacteremia and 46 strains from neonates with bacteremia. O-antigenic types O6, O4, O2, O16, O18, and O7 were observed most frequently, but their relative prevalence did not differ materially between adult and neonatal bacteremias. A greater proportion of strains from neonatal bacteremia contained K1 antigen and were autoagglutinable compared with strains from adult bacteremia, although K1 was the most frequent K antigen found in strains from adults. K-antigen-containing strains did not appear to be associated with enhanced severity of bacteremia, but nontypable strains, auto-agglutinable strains, and strains of O-antigenic types O4, O6, and O8 were associated with a greater frequency of shock and fatal outcome in adults. No differences could be detected between the serum sensitivities of E. coli isolated from adult bacteremia and those from neonatal bacteremia. K antigen did not affect serum sensitivity, but E. coli strains of O types O18, O2, O4, and O7 were more serum-resistant than other E. coli. Bacteremia caused by serum-sensitive E. coli was less often associated with shock and death than bacteremia caused by serum-resistant E. coli.

Adult↗
PubMed1978

Intravenous gamma-globulin infusions in patients with hypo-gamma-globulinemia: prevention of adverse reactions with corticosteroids.

A gamma-globulin preparation for intravenous use was given to 11 patients with antibody deficiency syndromes. Most of them had reacted earlier to intramuscular injections of normal gamma-globulin. The gamma-globulin employed produced adverse reactions, often quite severe in 8 of 9 intravenous infusions in three patients. After premedication with hydrocortisone, side effects appeared on 18 of 48 occasions in 10 patients, but only twice were they so severe that the infusions had to be interrupted. Thus, it seems that hydrocortisone diminishes the risk of side effects. The intravenously administered gamma-globulin seemed to be just as effective as the preparations for intramuscular use, and no severe infections appeared during the period of observation. There was no indication that the single hydrocortisone injections, usually 200 mg, increased the risk of contracting infections, but still such medication should be used with great caution in antibody-deficient patients.

Adult↗
PubMed1978

New knowledge in human milk immunoglobulin.

One of the anti-infection principles of maternal milk is the predominant milk immunoglobulin, secretory IgA. This immunoglobulin contains antibodies against many pathogens and potential pathogens, viruses as well as bacteria, including several members of Enterobacteriacae. The antigenic stimuli for these milk antibodies seem to take place in the Peyer's patches of the intestine. Lymphoid cells leaving the patches after antigenic exposure seem to home to the mammary glands via the lymph and blood circulation. As a result, the milk contains secretory IgA antibodies against, among other things, the intestinal bacteria of the mother. These milk antibodies might reflect the spectrum of bacteria and viruses in the community and may be important for the protection of the breast-fed baby. Via the same homing mechanism the maternal milk obtains antibodies against dietary antigens, including cow's milk proteins. Studies of infants on mixed feeding suggest that the secretory IgA antibodies against the bovine proteins diminish the antigenic exposure, indicating the possibility of an anti-allergic mechanism.

Antibody Formation↗