Immunogenicity in Weanling Rabbits of a Polyribophosphate Complex from Haemophilus influenzae Type b

Abstract

Polyribophosphate (PRP), the capsular polysaccharide of Haemophilus influenzae type b, is more effectively immunogenic when it is associated with the bacterium than when it is in the purified form that is being tested as a vaccine for humans. In an effort to analyze this difference, we isolated from H. influenzae type b a high-molecular-weight, soluble complex, in which PRP appears to be combined with protein (about 7% protein). The pyrogenicity and limulus lysate gelation activity of the complex suggest that a small amount of lipopolysaccharide also is present. The protein was resolved into five polypeptides by electrophoresis in polyacrylamide gel containing sodium dodecyl sulfate. In weanling rabbits, which do not respond to purified PRP, the complex induces high titers of antibody of PRP, in an anamnestic pattern. Bactericidal antibody to other bacterial components was also elicited. Equilibrium density gradient centrifugation of the complex indicated that most of the immunogenicity of PRP resides in the least dense fractions, which are high in protein, low in polysaccharide, and active in the limulus lysate test; denser fractions that react strongly with limulus lysate but are poor in protein were much less immunogenic.

Complex of Meningococcal Group B Polysaccharide and Type 2 Outer Membrane Protein Immunogenic in Man

“…We have verified the presence ofbactericidal antibodies specific for the serotype proteins in convalescent phase human sera; and, in contrast to the findings of Wyle et al (15) and Kasper et al (17), we have found that most adult human sera contain bactericidal antibodies specific for the group B polysaccharide (8). 2 The latter result suggested that group B-specific bactericidal antibodies might be induced by vaccination if the antigen were properly presented.…”

“…These results suggested that outer membrane protein might function as an effective carrier for the group B capsular polysaccharide. Naturally occurring complexes of the capsular polysaccharide from Haemophilus influenzae and N. meningitidis with protein (presumably outer membrane protein) have been shown to exhibit increased immunogenicity in animals as compared with the purified polysaccharides (17,18). In addition, induction ofantibodies to both the group B polysaccharide and the serotype protein(s) may result in better protection than either specificity ofantibody alone (19).…”

Αιμοφιλος Της Γριππης Στα Παιδια

“…Ενεργητική ανοσοποίηση μέ εμβόλιο, πού περιέχει το αντιγόνο του όροτύπου b δέν δίνει προστασία για λοιμώξεις σέ παιδιά κάτω των δύο ετών, παιδιών δηλαδή πού έχουν τή μεγαλύτερη ανάγκη προστασίας. Προ σπάθεια μέ τέτοιο στόχο γίνεται άπό τους Anderson καί Smith (1977).…”

“…Δέν νομίζουμε δτι έχει καμμία πρακτική σημασία στα διαγνωστικά νοσοκομειακά εργαστήρια. 4. Για τήν όροτυπία των 121 στελεχών του //.…”

“…Τό πλέον διαχωριστικό χαρακτηριστικό του γένους των Haemophi lus άπό τα άλλα συγγενικά γένη είναι ή ανάγκη παρουσίας παραγόντων αναπτύξεως στο θρεπτικό υλικό, παραγόντων πού βρίσκονται κυρίως στο αίμα ή και σέ άλλες ουσίες όπως ή αίμίνη (παράγων Χ) και τό NAD ή ΤΡΝ (παράγων V) (Zinnemann 1967(Zinnemann , Παπαβασιλείου -Λεγάκης, 1978 Bacteriology, 1974, αναγρά φονται οί κατωτέρω οργανισμοί σαν Species incertae sedis τοΰ γένους των Haemophilus α) Η. ovis, β) Η. putoriorum, γ) Η. citreus, δ) Η. piscium, ε) Η. aegyptius και σαν νεώτερο είδος Η. s e guis ò ). 4 Από τα 19 εϊδη του γένους, τα πέντε απαιτούν τους Χ και V παράγον τες (Η. influenzae, Η. suis, Η. haemolytiens, Η. gallinarum καί Η. aegyptius).).…”