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Biomedical subjects

L Gothefors

Publications and source records attributed to L Gothefors.

At least 55 records · Page 3Linked to original sources
PubMed1987

Serum antibody response to capsular polysaccharide, outer membrane, and lipooligosaccharide in children with invasive Haemophilus influenzae type b infections.

Serum antibodies against capsular polysaccharide (CPS), outer membrane (OM), and lipooligosaccharide (LOS) from Haemophilus influenzae type b were measured by enzyme-linked immunosorbent assay in acute- and convalescent-phase sera from 21 children between 3 months and 4 years of age with invasive H. influenzae type b infections. As expected, the levels of anti-CPS antibodies in the acute-phase serum samples were low or not detectable, as were the levels of antibodies against LOS. In contrast, all children had detectable antibodies against the OM in the acute-phase serum sample, indicating that they are of little or no importance for protection. An antibody response to CPS was noted in 13 of the 21 patients, mainly in the older children. An antibody response to the OM was seen in 16 patients, with no evident relation to age. The antibody response to the OM preparation, which consisted of proteins and LOS, was probably directed mainly against the OM proteins, since only six children showed a response, usually of low magnitude, of antibodies to LOS.

Antibodies, Bacterial↗
PubMed1986

Local and systemic antibody responses to naturally acquired enterotoxigenic Escherichia coli diarrhea in an endemic area.

Fifteen patients hospitalized with acute, watery diarrhea and with enterotoxigenic Escherichia coli (ETEC) detected from stool samples were studied to evaluate the extent to which natural ETEC diarrhea induces local and systemic antibody responses to E. coli heat-labile toxin (LT), homologous lipopolysaccharide (LPS), and colonization factors (CFA/I and CFA/II). Specific IgA and IgG antibodies to LT, CFA I and II, and each patient's homologous LPS were determined by ELISA in serum, saliva, breastmilk, and intestinal lavage fluid. The majority of patients had greater than a twofold rise in local levels of IgA antibodies in the intestine: 80% of LT+ patients responded to LT, 63% of CFA+ patients responded to CFA, and 78% of all toxin-positive patients responded to the LPS of their infecting strain. Local antibody responses in the intestine were associated with responses in breastmilk and saliva, but relationships were not clear-cut, and the usefulness of these secretions as proxy measures of local intestinal antibody production remains unclear. Antibody responses in serum also occurred in most patients and were significantly more frequent in cases than in controls. This study demonstrates that natural ETEC disease results in local IgA responses to LT, CFA, and LPS in the gut and also in immune responses in breastmilk, saliva, and serum.

Adult↗
PubMed1986

Comparison of methods for detection of colonization factor antigens on enterotoxigenic Escherichia coli.

Fecal Escherichia coli isolates from 196 patients with watery diarrhea and 68 healthy individuals (controls) were analyzed in Bangladesh immediately after isolation for the presence of colonization factor antigen (CFA) I or II (CFA/I or CFA/II, respectively) by a mannose-resistant hemagglutination (MRHA) test with six species of erythrocytes and by a slide agglutination test with absorbed CFA/I or CFA/II antisera. The presence of CFAs was confirmed by immunodiffusion analyses done in Sweden. By these methods, it was found that 49 of 69 enterotoxin-producing E. coli strains isolated from patients carried CFA/I or CFA/II, whereas none of the nonenterotoxigenic E. coli isolates or the three toxin-positive strains isolated from healthy individuals carried these adhesins. All E. coli strains retained their MRHA ability after transportation to Sweden followed by one subculture and after storage at -70 degrees C (but not at room temperature) for 1 to 2 years without further subculturing. After 5 to 10 subcultures of the fresh isolates, however, 70% of the initially CFA/I- and 80% of the initially CFA/II-carrying strains analyzed did not hemagglutinate. The efficacy of different methods for detecting CFAs on the fresh isolates was compared with that of immunodiffusion. The sensitivity of MRHA with human blood group A erythrocytes for the detection of CFA/I was high (97%), but the specificity was only 69%. The sensitivity of MRHA with bovine erythrocytes for the detection of CFA/II in Bangladesh was very low but increased considerably when chicken erythrocytes were also used. Whereas both false-positive and false-negative reactions were obtained when absorbed CFA antisera were used for agglutination, antisera against purified CFAs were equally effective as immunodiffusion in identifying CFA/I and CFA/II-carrying strains.

Agglutination Tests↗
PubMed1985

Presence of colonization factor antigens on fresh isolates of fecal Escherichia coli: a prospective study.

In Dhaka, Bangladesh, fresh isolates of Escherichia coli from 197 patients with diarrhea were investigated for production of enterotoxin and possession of colonization factor antigen (CFA) I or II. Enterotoxigenic E. coli (ETEC) was isolated from 34% of the patients, and of the 67 enterotoxin-positive strains, 75% carried CFAs. Among 68 healthy control persons no strains positive for both enterotoxin and CFA were found. The CFAs in general were restricted to certain serotypes of E. coli. In a subgroup of patients, part of an ongoing surveillance study, mixed infection was seen in 23% of those from whom recognized pathogens were identified. There was a tendency to more severe dehydration when the two virulence factors, enterotoxin and CFA, were simultaneously present.

Antigens, Bacterial↗
PubMed1984

Mucosal antitoxic and antibacterial immunity after cholera disease and after immunization with a combined B subunit-whole cell vaccine.

Mucosal and systemic immune responses to a new oral cholera vaccine, consisting of the B subunit plus killed vibrios, were studied in Bangladeshi volunteers and compared with those to clinical cholera. A single peroral dose of vaccine induced a local IgA antitoxin response in intestinal-lavage fluid of seven of eight vaccinees; the response closely mimicked that of patients convalescing from cholera, and evidence of the induction of local immunologic memory was found as well. Two peroral doses were needed for stimulation of an intestinal IgA immune response to the lipopolysaccharide of Vibrio cholerae that was comparable to the response obtained after clinical cholera. This response to peroral immunization was considerably stronger than that to parenteral vaccination, although the intramuscular route gave rise to the strongest IgG antitoxin and antilipolysaccharide responses in serum. The results suggest that B subunit-whole cell vaccine, when given in at least two oral doses, may be a good candidate for use in cholera prophylaxis.

Administration, Oral↗
PubMed1984

Local and systemic antibody responses and immunological memory in humans after immunization with cholera B subunit by different routes.

A single oral or intramuscular immunization with purified cholera B subunit induced an intestinal secretory immunoglobulin A (IgA) antitoxin response in, respectively, 10 out of 11 and 9 out of 12 Bangladeshi volunteers. The IgA titre rise in intestinal lavage fluid was similar by either route of immunization, but the duration of the response was usually longer after the oral dose. A second immunization by either route, given 25 days after the first, and a third dose (oral only), given 15 months later, resulted in intestinal immune responses which did not differ in magnitude from that induced by the initial immunization but were observed significantly earlier, usually by day 3. Both the first oral and intramuscular immunizations induced significant antitoxin titre rises, mainly IgG, in the serum in most vaccinees but the magnitude of the response was considerably higher after the intramuscular dose. Significant IgA antitoxin titre rises in saliva and breast milk were seen after both oral and intramuscular immunization.

Administration, Oral↗
PubMed1983

Current status of an oral B subunit whole cell cholera vaccine.

Purified B subunit of cholera toxin retains membrane-binding capacity and protective immunogenicity and yet has no toxic activity as tested in animals. These properties suggest that B subunit might be a promising immunogen, particularly as an oral vaccine, for stimulating protective antitoxic immunity against cholera in man. A method has been elaborated which allows preparation of +/- 10 grams of pure B subunit per fermentor culture cycle. As tested in both Swedish and Bangladeshi volunteers purified B subunit alone or in combination with conventional whole cell vaccine gives no side-effects at all when given orally and only very mild local reactions after parenteral administration. A single peroral or intramuscular immunization with B subunit has given significant intestinal IgA antitoxin antibody formation in 75-85% of Bangladeshi women tested; however, the duration of the response was longer after the oral route. The preliminary results of a recent study (Svennerholm, A.M., Jertborn, M., Gothefors, L., Karim, A., Sack, D. and Holmgren, J., to be published) have further shown that two peroral immunizations of Bangladeshi volunteers with a combined B subunit--whole cell cholera vaccine give rise to mucosal IgA antitoxin as well as anti-lipopolysaccharide antibody formation which closely resemble these antibody responses in cholera convalescents. The combined vaccine also evoked a local immunologic memory comparable to that induced by clinical disease.

Antibody Formation↗
PubMed1982

Rapid technique for detection of pneumococcal pneumonia.

Tracheal aspirates from patients with diarrhoea and pneumonia were tested for the presence of pneumococci by both quantitative culture and counter immunoelectrophoresis (CIE). Antigen was demonstrated by CIE in 33/48 of these confirmed cases of pneumonia. The technique is easy to use and gives rapid results.

Adolescent↗
PubMed1980

Collecting and banking human milk: to heat or not to heat?

Data on human breast milk and its handling when fed to babies who cannot be breast-fed were reviewed to determine whether the method of processing and storage affected the properties of the milk. Breast milk is normally contaminated by potential pathogens, which seem to produce no ill effects, but it also contains antimicrobial properties which protect against infection. The evidence suggests that pasteurisation not only eliminates pathogenic bacteria but also damages bacteriostatic mechanisms, so making the milk more susceptible to later contamination. Pasteurisation also affects the nutritional properties of milk. Freezing has little effect on milk proteins, while a study on the effect of refrigeration showed that there was little bacterial growth at temperatures below 8 degrees C. Several years' experience of feeding donated raw milk to newborn infants has confirmed that it produces no ill effects. These findings suggest that pasteurisation of donated breastmilk is unnecessary, and it is not recommended, while the decision whether or not to freeze the milk may be made on practical grounds. Raw breast milk can be safely stored at 4-6 degrees C for 72 hours.

Bacteria↗
PubMed1979

The effect of human colostrum on neutrophil function.

Strains of Escherichia coli were opsonized in human colostrum via heat stable opsonins and the classic complement pathway, but colostrum lacked capacity to opsonize E. coli via the alternative pathway. There was no bacteriostatic activity against serum sensitive E. coli strains, although specific antibodies against the strains were present. Neutrophils suspended in colostrum had normal chemotaxis and this was not altered by treating the colostrum with HCl.

Chemotaxis, Leukocyte↗
PubMed1976

Interaction of E. coli strains with human serum: lack of relationship to K1 antigen.

Twenty-eight strains of E. coli isolated from infants were compared with respect to opsonic requirements, sensitivity to serum, and ability to activate serum chemotactic factors. Six of the strains were isolated from stools of healthy newborn infants; 22 were isolated from the cerebrospinal fluid or blood of infants with meningitis and/or septicemia. Eighteen of the strains had K1 polysaccharide antigen. Fourteen of the strains (seven with K1 antigen) activated complement via the alternative pathway and all of these strains were well opsonized in 4% pooled human serum. A higher concentration of serum was necessary to opsonize 12 of the 14 strains that did not activate the alternative pathway. A wide variation was also found in opsonic requirements of E. coli strains isolated from healthy and sick infants. There was no relationship of the K1 antigen to opsonic requirements, to capacity to activate complement via the alternative pathway, to generation of chemotactic factors, or to sensitivity to serum cidal activity. Therefore, the association of E. coli with K1 antigen and neonatal meningitis did not appear to be related to these bacteria-serum interactions.

Antigens, Bacterial↗
PubMed1976

Studies of Escherichia coli O antigen specific antibodies in human milk, maternal serum and cord blood.

Studies of Escherichia coli O antigen specific antibodies in human milk, maternal serum and cord blood. Acta Paediatr Scand, 65:216, 1976.--The quantity and class specificity of E. coli O antibodies in human milk, maternal serum and cord blood was determined by the enzyme-linked immunosorbent assay. The predominant Ig-class of these antibodies in milk was IgA. The initially high levels of antibodies decreased 10-fold during the first days, but there seemed to be a fairly constant daily production of IgA antibodies during the first two months of the nursing period. There was no obvious decline in antibody content from morning to night or during a meal. The ratio milk antibody/serum antibody was very high for IgA, suggesting a local production. The ratios for the IgG were all less than 1, suggesting a restricted transfer from the serum. Ratios around 1 for IgM did not exclude some local production. In umbilical cord serum the amount of IgG E. coli O antibodies was higher than that in maternal serum. Small amounts of IgM and IgA antibodies was also demonstrated in some cases. In milk as well as in serum there were antibodies against a wide variety of E. coli O groups, not only to the actual E. coli strain dominating the mother's gut flora.

Antibodies, Bacterial↗
PubMed1976

Influence of maternal gut flora and colostral and cord serum antibodies on presence of Escherichia coli in faeces of the newborn infant.

From 29 healthy newborn infants and their mothers faecal, serum and milk specimens were obtained on several occasions from one to nine weeks after delivery. Predominant faecal E. coli were serotyped with regard to the O antigen and milk and serum were analysed for their content of E. coli O antibodies by the enzyme-linked immunosorbent assay. In five cases the babies acquired the same O serotype as was found in the stools of their mothers but in 12 out of 29 cases infant and mother never had any dominating faecal E. coli O type in common. There was no apparent correlation between the patterns of feeding and interchange of bacteria. Klebsiella/Enterobacter was the dominating facultative organism on at least one occasion in half the infants. The newborns received colostral IgA and transplacental circulating IgG antibodies against a great number of E. coli O serotypes. These antibodies did not prevent intestinal colonization, as judged from cultures of faeces.

Antibodies, Bacterial↗
PubMed1975

Studies on maturity in newborn infants. VII. Foetal haemoglobin.

Cord blood from 125 newborns of various gestational ages has been analysed for the ratio foetal haemoglobin to total haemoglobin, using an alkali denaturation method. The quotient, percentage of foetal haemoglobin divided by birth weight correlates well with gestational age. Thus the percentage of foetal haemoglobin in cord blood can be used as a method for estimating maturity in newborn infants. Foetal haemoglobin has been compared with other methods for maturity assessments and seems to give the same precision in estimating gestational age as the best of these, which is the scoring of external characteristics. However, the latter method is considerably less time-consuming and more suitable for routine use.

Apgar Score↗