Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Biological activity of serum antibodies to a nonacylated form of lipoprotein D of Haemophilus influenzae

Akkoyunlu, Mustafa ; Janson, Håkan LU ; Ruan, Maorong and Forsgren, Arne LU (1996) In Infection and Immunity 64(11). p.4586-4592
Abstract
Protein D, a surface-exposed 42-kDa membrane lipoprotein, is well conserved among both type b and nontypeable Haemophilus influenzae strains, and it is considered a vaccine against H. influenzae infections. Here, we report the large-scale purification of a nonacylated form of protein D (PDm) from the periplasmic space of Escherichia coli overexpressing PDm. Screening of human sera for levels of antibodies to PDm demonstrated that the immunoglobulin G (IgG) antibody level is above background levels in infants less than 6 months of age. Following a drop to background values in the age group 6 months to 1 year, IgG antibody levels start to increase, together with IgA antibody levels, after 1 year of age. The first appearance of serum IgM... (More)
Protein D, a surface-exposed 42-kDa membrane lipoprotein, is well conserved among both type b and nontypeable Haemophilus influenzae strains, and it is considered a vaccine against H. influenzae infections. Here, we report the large-scale purification of a nonacylated form of protein D (PDm) from the periplasmic space of Escherichia coli overexpressing PDm. Screening of human sera for levels of antibodies to PDm demonstrated that the immunoglobulin G (IgG) antibody level is above background levels in infants less than 6 months of age. Following a drop to background values in the age group 6 months to 1 year, IgG antibody levels start to increase, together with IgA antibody levels, after 1 year of age. The first appearance of serum IgM antibodies is in 6-month- to 1-year-old infants whose IgG antibody levels have dropped to the postnatal background level. Affinity-purified antibodies from humans and from PDm-immunized rats detected epitopes of protein D which are normally exposed on the bacterial surface. Affinity-isolated human anti-PDm antibodies eluted in acidic buffer were not bactericidal against H. influenzae. Loss of bactericidal activity may occur in this buffer, as was demonstrated in pooled human sera with high bactericidal activity after incubation in the same buffer. Hyperimmunization of rats with PDm induced high levels of serum IgG and IgA antibodies against PDm and significant bactericidal activity against homologous and heterologous H. influenzae strains. (Less)
Please use this url to cite or link to this publication:
author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Infection and Immunity
volume
64
issue
11
pages
4586 - 4592
publisher
American Society for Microbiology
external identifiers
  • pmid:8890211
  • scopus:0029910860
ISSN
1098-5522
language
English
LU publication?
yes
id
e0f168b9-f1b4-4a03-a23c-fcdb557295b5 (old id 1110189)
alternative location
http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=174417&blobtype=pdf
date added to LUP
2016-04-01 12:06:39
date last changed
2022-01-26 22:57:25
@article{e0f168b9-f1b4-4a03-a23c-fcdb557295b5,
  abstract     = {{Protein D, a surface-exposed 42-kDa membrane lipoprotein, is well conserved among both type b and nontypeable Haemophilus influenzae strains, and it is considered a vaccine against H. influenzae infections. Here, we report the large-scale purification of a nonacylated form of protein D (PDm) from the periplasmic space of Escherichia coli overexpressing PDm. Screening of human sera for levels of antibodies to PDm demonstrated that the immunoglobulin G (IgG) antibody level is above background levels in infants less than 6 months of age. Following a drop to background values in the age group 6 months to 1 year, IgG antibody levels start to increase, together with IgA antibody levels, after 1 year of age. The first appearance of serum IgM antibodies is in 6-month- to 1-year-old infants whose IgG antibody levels have dropped to the postnatal background level. Affinity-purified antibodies from humans and from PDm-immunized rats detected epitopes of protein D which are normally exposed on the bacterial surface. Affinity-isolated human anti-PDm antibodies eluted in acidic buffer were not bactericidal against H. influenzae. Loss of bactericidal activity may occur in this buffer, as was demonstrated in pooled human sera with high bactericidal activity after incubation in the same buffer. Hyperimmunization of rats with PDm induced high levels of serum IgG and IgA antibodies against PDm and significant bactericidal activity against homologous and heterologous H. influenzae strains.}},
  author       = {{Akkoyunlu, Mustafa and Janson, Håkan and Ruan, Maorong and Forsgren, Arne}},
  issn         = {{1098-5522}},
  language     = {{eng}},
  number       = {{11}},
  pages        = {{4586--4592}},
  publisher    = {{American Society for Microbiology}},
  series       = {{Infection and Immunity}},
  title        = {{Biological activity of serum antibodies to a nonacylated form of lipoprotein D of Haemophilus influenzae}},
  url          = {{http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=174417&blobtype=pdf}},
  volume       = {{64}},
  year         = {{1996}},
}