Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To assess the role of interleukin-12 (IL-12) and gamma interferon (IFN-gamma) in children with bacterial meningitis, bioactive IL-12 (p70) and the inactive subunit p40 and IFN-gamma were measured in serum and cerebrospinal fluid (CSF) from 35 children with bacterial meningitis and 10 control subjects. The production of IFN-gamma is induced by IL-12 with tumor necrosis factor alpha (TNF-alpha) as a costimulator and inhibited by IL-10. CSF concentrations of IL-12 p40 as well as those of IFN-gamma were markedly elevated, whereas IL-12 p70 was hardly detectable. Detectable CSF levels of IFN-gamma correlated positively with IL-12 p40 (r = 0.40, P = 0.02) and TNF-alpha (r = 0.46, P = 0.04) but not with IL-6, IL-8, or IL-10. In contrast to CSF levels of TNF-alpha, IL-12, and IL-10, those of IFN-gamma were significantly higher in patients with pneumococcal meningitis than in children with meningitis caused by Haemophilus influenzae and Neisseria meningitidis, presumably because of a high CSF TNF-alpha/IL-10 ratio in the former. We suggest that IL-12- and TNF-alpha-induced IFN-gamma production may contribute to the natural immunity against microorganisms in the CSF compartment during the acute phase of bacterial meningitis.
 ...
PMID:Intrathecal production of interleukin-12 and gamma interferon in patients with bacterial meningitis. 903 91

Intraperitoneal inoculation of Haemophilus influenzae type b (Hib) to 3-week-old Sprague-Dawley rats resulted in nonlethal meningitis with high levels of leukocytes in the cerebrospinal fluid (CSF) and positive bacterial culture. Using in situ hybridization, levels of cytokine mRNA-expressing cells were determined in the brain, CSF, and spleen from Hib-inoculated and uninfected control rats. IFN-gamma, IL-1 beta, IL-4, IL-6, IL-10, IL-12, and TNF-alpha mRNA levels were elevated at 12 hr postinoculation (pi) in spleen and CSF. At this time point, strong expression of IL-6 and TGF-beta was detected in the brain, and also of IL-10 at 48 hr while IFN-gamma and IL-12 were expressed at very low levels throughout the observation time. Delayed cytokine induction occurred in CSF compared to spleen and brain. TGF-beta was high in CSF at 48 hr, and some elevation of IL-1 beta, IL-6, IL-10, TNF-alpha, IFN-gamma, and IL-12 was evident at 72 hr pi. This may suggest measures that promote production of TGF-beta and/or IL-10 should be evaluated in treatment of bacterial meningitis.
 ...
PMID:Cytokine mRNA profiles during the course of experimental Haemophilus influenzae bacterial meningitis. 940 Jun 23

We have previously shown that tonsil tissue both from children with tonsillar hypertrophy and recurrent tonsillitis is colonized and invaded by Haemophilus influenzae and Streptococcus pyogenes group A. In order to evaluate if these bacteria are involved in the immunopathogenesis of these two conditions, tonsillar cells from both groups were stimulated in vitro with intact, heat-inactivated H. influenzae or S. pyogenes A. The immunoreactivity was evaluated by assessing the induction of cytokine production (IL-1 alpha, IL-1 beta, TNF-alpha, IL-6, IL-8, IL-2, IFN-gamma, IL-4, TNF-beta and IL-10), which was detected at the single-cell level. All cytokines studied except IL-4 were induced in both groups after stimulation with H. influenzae or S. pyogenes A. The dominating cytokines were IL-1 beta, IFN-gamma and TNF-beta. No major differences in the cytokine pattern or number of cytokine-producing cells were noticed between the two patient cohorts after H. influenzae stimulation. Activation by S. pyogenes A bacteria gave rise to higher frequencies of IFN-gamma- and TNF-beta-synthesizing cells in the recurrent tonsillitis group. The incidence of CD4-, CD8-positive T cells and CD40-positive B cells was comparable between the two groups while the MAC-387-positive macrophages were significantly higher in the recurrent tonsillitis groups. In conclusion, a Th1 type of cytokine response was found in both groups following stimulation with H. influenzae or S. pyogenes A.
 ...
PMID:Haemophilus influenzae and Streptococcus pyogenes group A challenge induce a Th1 type of cytokine response in cells obtained from tonsillar hypertrophy and recurrent tonsillitis. 951 80

Levels of the pro-inflammatory cytokines TNF-alpha and IFN-gamma were measured from the time of infection to the time of complete clearance of non-typeable Haemophilus influenzae (NTHi) from the lung in immune and non-immune rats. Mucosal immunization facilitated production of significant levels of TNF-alpha as early as 30 min post-pulmonary challenge with NTHi in immune animals. Following the peak at 2 h, rapid decline of TNF-alpha levels occurred from the alveolar spaces. Levels of TNF-alpha in non-immunized animals increased at a slower rate, peaked at a lower concentration and were slower to decline. The significantly larger number of macrophages seen in the immune animals at 1 h after bacterial challenge could partially account for the higher levels of TNF-alpha. Interferon-gamma was not detected in immune or non-immune rats at any time point before NTHi clearance after pulmonary challenge. Study of the kinetics of TNF-alpha release demonstrates that immunized animals control the release of pro-inflammatory cytokines more effectively than non-immunized animals for enhanced clearance of bacterial infection from the lungs.
 ...
PMID:Kinetics of inflammatory cytokines in the clearance of non-typeable Haemophilus influenzae from the lung. 989 34

The aim of this study was to analyse the in vitro response of human peripheral blood mononuclear cells to stimulation with killed Haemophilus influenzae strains of different capsular types, isolation sites and from cases with different forms of infections. The mean stimulatory index using 10(6) bacteria/well was 10, and 80 when 10(8) bacteria/well were used for stimulation. The mean+/-SD level was 13+/-4 ng/ml for interleukin (IL)-1beta, 128+/-73 ng/ml for IL-6, 203+/-122 ng/ml for IL-8, 3160+/-1220 pg/ml for IL-10, 29+/-40 pg/ml for IL-12, 2800+/-1790 pg/ml for tumour necrosis factor (TNF)-alpha and 4+/-7 ng/ml for interferon (IFN)-gamma, when stimulating cells with the lower dose of 10(6) bacteria/well. Using the higher bacterial dose, the levels of IL-1beta, TNF-alpha and IL-12 remained similar, whereas the IL-6, IL-8 and IL-10 levels were significantly lower, and IFN-gamma levels were significantly higher. Strains isolated from the bronchial tree induced significantly higher levels of IFN-gamma and significantly lower levels of IL-6, IL-8 and IL-10 than strains from other isolation sites. In conclusion, H. influenzae generated phagocyte-activating cytokines and an IL-10/IL-12 ratio that was 1090 times that described previously for Streptococcus pneumoniae.
 ...
PMID:Induction of phagocyte-stimulating cytokines by in vitro stimulation of human peripheral blood mononuclear cells with Haemophilus influenzae. 1021 68

Synthetic oligodeoxynucleotides containing CpG motifs [immunostimulatory sequences (ISS)] have been described as potent adjuvants of type 1 immune responses when co-administered with protein or peptide vaccines. To investigate their role in the immune response to polysaccharides (CHO), different preparations of anti-Haemophilus influenzae type b (Hib) conjugate vaccine were administered to mice. The unconjugated CHO did not induce the synthesis of specific antibodies even in the presence of ISS. On the other hand, anti-CHO-specific antibodies significantly increased in the presence of ISS, when tetanus (TT) or diphtheria [cross-reacting material (CRM)] toxoid-conjugated CHO were used to immunize mice. The adjuvant effect was also observed for the immune response against the carrier protein (TT and CRM). ISS insured an early and long-lasting specific IgG production. The effects of ISS on the anti-CHO immune response could be attributed to the amplification of the T help provided by the carrier. The analysis of anti-CHO IgG subclasses showed a significant increase of IgG2a and IgG3 in the presence of ISS. ISS caused a rapid release of IL-12 and IFN-gamma in sera from treated mice. This data provide a first evidence for the ability of ISS to induce an anti-CHO type 1-like immune response and demonstrate that ISS have the potential to increase host antibody response against both the CHO and the protein component of a conjugated vaccine.
 ...
PMID:Synthetic oligodeoxynucleotide containing CpG motif induces an anti-polysaccharide type 1-like immune response after immunization of mice with Haemophilus influenzae type b conjugate vaccine. 1070 Apr 64

CNI-1493, a potent macrophage deactivator, was used to treat infant rats systemically infected with Haemophilus influenzae type b (Hib). CNI-1493 was injected 1 h prior to bacterial inoculation and 24 h later and resulted in a 75 percent increased rate of survival compared to that for untreated controls. The effect of CNI-1493 on the inflammatory response was studied by immunohistochemical detection of individual tumor necrosis factor alpha (TNF-alpha)-, interleukin 1 beta (IL-1beta)-, and gamma interferon (IFN-gamma)-producing cells in the spleen. A significant reduction of the incidence of TNF-alpha- and IL-1beta-expressing cells was found for CNI-1493-treated animals. IFN-gamma expression was not suppressed by CNI-1493, indicating that cytokine inhibition was specific in macrophages. CNI-1493 significantly reduced the number of infiltrating granulocytes in the brain from that for controls. This study provides evidence that CNI-1493 protects against lethal Hib infection by deactivating the inflammatory cascade in infant rats.
 ...
PMID:Suppression of macrophage activation with CNI-1493 increases survival in infant rats with systemic Haemophilus influenzae infection. 1094 62

Protein databases were searched for microbial sequences that bear amino acid similarities with identified T- or B-cell epitopes within the human alpha-subunit of acetylcholine receptor (AChR). One peptide, derived from Haemophilus influenzae, exhibits 50% homology to an identified T-cell epitope of AChR alpha-subunit. This peptide was shown to have a protective effect in experimental autoimmune myasthenia gravis (EAMG). Pretreatment of rats with the mimicry peptide attenuated the induction and progression of EAMG. These effects were accompanied by a reduced T-cell response to AChR, diminished IL-2, IL-12, IFN-gamma and IL-4 levels, as well as decreased humoral response to self-AChR.
 ...
PMID:Protective molecular mimicry in experimental myasthenia gravis. 1202 Sep 61

The expression of inducible antimicrobial peptides, such as human beta-defensin-2 (HBD-2) by epithelia, comprises a component of innate pulmonary defenses. We hypothesized that HBD-2 induction in airway epithelia is linked to pattern recognition receptors such as the Toll-like receptors (TLRs). We found that primary cultures of well-differentiated human airway epithelia express the mRNA for TLR-4, but little or no MD-2 mRNA, and display little HBD-2 expression in response to treatment with purified endotoxin +/- LPS binding protein (LBP) and soluble CD14. Expression of endogenous MD-2 by transduction of airway epithelial cells with an adenoviral vector encoding MD-2 or extracellular addition of recombinant MD-2 both increased the responses of airway epithelia to endotoxin + LBP and sCD14 by >100-fold, as measured by NF-kappaB-luciferase activity and HBD-2 mRNA expression. MD-2 mRNA could be induced in airway epithelia by exposure of these cells to specific bacterial or host products (e.g., killed Haemophilus influenzae, the P6 outer membrane protein from H. influenzae, or TNF-alpha + IFN-gamma). These findings suggest that MD-2, either coexpressed with TLR-4 or secreted when produced in excess of TLR-4 from neighboring cells, is required for airway epithelia to respond sensitively to endotoxin. The regulation of MD-2 expression in airway epithelia and pulmonary macrophages may serve as a means to modify endotoxin responsiveness in the airway.
 ...
PMID:Endotoxin responsiveness of human airway epithelia is limited by low expression of MD-2. 1512 39

To evaluate the early stages of the host response to chancroid bacterium Haemophilus ducreyi, we investigated the in vitro responses of monocyte-derived dendritic cells (DCs) and macrophages (MQs) to this pathogen and Haemophilus influenzae. The phagocytic activities and pro-inflammatory cytokine secretion profiles of the antigen-presenting cells (APCs) were analyzed after exposure to gentamycin-killed bacteria, H. ducreyi lipooligosaccharide (LOS), and purified cytolethal distending toxin (HdCDT). T-cell proliferation and cytokine release were examined after co-culturing isolated autologous CD4+ T cells with antigen-pulsed APCs. Both the DCs and MQs phagocytosed H. ducreyi and H. influenzae, as estimated by flow cytometry. All of the strains induced APC secretion of TNF-alpha, IL-6, IL-8, and IL-12, as measured by ELISA. Other human cells, particularly endothelial cells and fibroblasts, also produced cytokines when stimulated with these bacteria. Purified LOS at concentration 1 microg/ml induced two to threefold lower levels of cytokines than the whole bacteria, which indicates that other components are involved in immune activation. HdCDT inhibited partially the production of the aforementioned cytokines. High levels of IFN-gamma, but not of IL-4 and IL-13, were secreted by T cells after activation by either DCs or MQs that were pre-exposed to bacteria, indicating the Th1 nature of the immune response. The levels of T-cell proliferation induced by H. ducreyi were lower than those induced by H. influenzae. HdCDT-treated APCs did not display cytokine responses or T-cell proliferation. These results indicate that HdCDT intoxication, which results in progressive apoptosis of APCs, may hamper early stage immune responses.
 ...
PMID:Interactions of Haemophilus ducreyi and purified cytolethal distending toxin with human monocyte-derived dendritic cells, macrophages and CD4+ T cells. 1548 36


1 2 3 Next >>