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This study compared the protein composition of breast milk and the nutrient intake between Thai and Japanese lactating mothers. The breast milk was collected from 15 Thai and 14 Japanese mothers at the fifth day post-partum. Twenty-four-hour dietary records were performed from the second-to-the-fourth day post-partum. The nutrient intake was calculated by using the nutrient content of a food table. The protein composition of the whey was separated by gel electrophoresis and was identified by mass spectrometry and two-dimensional electrophoresis. The results showed that the concentrations of the major protein types in the breast milk were not significantly different between the two groups. The concentrations of the minor protein types varied markedly with the individuals, with higher concentrations in the breast milk of the Thai mothers. There were no significant differences in terms of the energy and protein intake; however, the sources of energy were different. The results indicate that the total protein and lactoferrin concentrations in the breast milk could be predicted by the maternal daily energy and fat intake. [ABSTRACT FROM AUTHOR]

Previously, we found that Kiebsiella O3 lipopolysaceharide (KO3 LPS) exhibits very strong adjuvant activity in augmenting the delayed-type hypersensitivity and antibody responses to protein antigens, and also strong ability to enlarge the regional lymph node in mice. By hydrolysis in 1% acetic acid at 100 for 1 hr. KO3 LPS was dissociated into 54-60% polysaccharide fraction and 25-27% lipid A fraction. The lipid A fraction thus prepared retained lethal toxicity for mice, whereas the polysaccharide fraction was essentially non-toxic. However, neither the lipid A fraction nor the polysaceharide fraction could reproduce the strong adjuvanticity of KO3 LPS, and a simple mixture of these two fractions also failed to do so. It is therefore concluded that, for expression of the strong adjuvanticity of KO3 LPS, both the lipid A and polysaccharide moieties are indispensable and must be combined in the form of LPS. By contrast, administration of relatively large amounts of the lipid A fraction alone could elicit enlargement of the regional lymph node to the same degree as that attained by KO3 LPS. The regional lymph node-enlarging activity of the lipid A fraction in lesser amounts was enhanced by addition of the polysaccharide fraction. It is therefore likely that there is no direct correlation between adjuvant activity of the LPS or its derivatives, and their regional lymph node-enlarging activity. [ABSTRACT FROM AUTHOR]

Klebsiella 03 lipopolysaccharide (LPS) and Escherichia coli 09 LPS were previously shown to have potent adjuvant activities in augmenting antibody response and delayed-type hypersensitivity to protein antigens. The R form LPS extracted from the O-specific polysaccharide-less mutants derived from Klebsiella 03 and E. coli 09 strains were characterized by chemical and electrophoretic analyses. The adjuvant activities of the R-LPS in augmenting antibody response and DTH to protein antigens were much weaker than those of the parental LPS. The strength of the adjuvant activities of the R-LPS was similar to that of the activities of Salmonella minnesota LPS and Ra-LPS. By contrast, polyclonal B-cell activation effects of the R-LPS were stronger than those of the parental LPS. The common feature of the parental LPS is that their O-specific polysaccharides are mannose homopolymers (mannans). From these results, it is suggested that mannose homopolymers as the O side-chains of LPS contribute to the action of LPS in enhancing strongly the T-cell dependent immune responses to protein antigens. [ABSTRACT FROM AUTHOR]

We have cloned a 13 kb Escherichia coli DNA fragment which complemented the rfe mutation to recover the biosynthesis of E. coli O9 polysaccharide. Using Tn5 insertion inactivation, the rfe gene was localized at the 1.5kb HindIII-EcoRI region flanking the rho gene. We constructed an rfe-deficient E. coli K-12 mutant by site-directed inactivation using a DNA fragment of the cloned 1.5 kb rfe gene. This also confirmed the presence of the rfe gene in the 1.5kb region. By simultaneous introduction of both the rfe plasmid and the plasmid of our previously cloned E. coli 09 rfb into this rfe mutant, we succeeded in achieving in vivo reconstitution of O9 polysaccharide biosynthesis. From sequence analysis of the rfe gene, a putative promoter followed by an open reading frame (ORF) was identified downstream of the rho gene. This ORF coincided with the position of the rfe gene determined by Tn5 analysis and site-directed mutagenesis. Furthermore, we identified the rff genes in the 10.5kb DNA flanking the rfe gene. We recognized at least two functional domains on this cloned rff region. Region I complemented a newly found K-12 rff mutant, A238, to synthesize the enterobacterial common antigen (ECA). Deletion of region II resulted in the synthesis of ECAs with shorter sugar chains. When the 10.5kb rff genes of the plasmid were inactivated by either deletion or Tn5 insertion, the plasmid lost its ability to give rise to transformants of the rfe mutants. [ABSTRACT FROM AUTHOR]

The antibody response to P-fimbriae of Escherichia coli in patients with upper urinary tract infections was investigated. In the sera of patients with pyelonephritis obtained at the initial visit to hospital (3 to 7 days after the onset of symptoms), a high incidence of antibodies to P-fimbriae was detected (12 out of 14 patients). P-fimbriated Escherichia coli strains were isolated from urine samples in all of these antibody-positive patients. Antibodies detected by ELISA using purified antigen were essentially IgG and specifically recognized P-fimbriae. These antibodies inhibited completely, or in some cases partially, mannose-resistant hemagglutination with P-fimbriated Escherichia coli. [ABSTRACT FROM AUTHOR]