Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032285 (pneumonia)
 54,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine the role that the host response to the chlamydial 60 kDa heat shock protein (hsp) plays in the pathogenesis of infertility, C3H/HeN (H-2k) and C57BL/6 (H-2b) mice were inoculated in the left ovarian bursa with 1 x 10(5) inclusion forming units of the Chlamydia trachomatis mouse pneumonitis (MoPn) biovar, and in the right ovarian bursa with mock-infected HeLa-229 cell extracts. Control mice were inoculated with mock-infected HeLa-229 cell extracts. These two strains of mice were chosen because the C3H mice mount a strong immune response to the 60 kDa hsp, whereas the C57BL/6 mice respond only weakly. Vaginal cultures obtained after inoculation were positive for 4 weeks in both strains of mice. Histological sections showed a marked acute inflammatory infiltrate that permeated all the layers of the oviduct and lasted for approximately 2 weeks in both strains. By the third week, mononuclear inflammatory cells were also observed and from 4 weeks after inoculation, hydrosalpinx formation was observed, particularly in the C3H mice. An inclusion immunofluorescence assay detected antibodies specific for chlamydia in the serum and the vaginal washes of the C3H and C57BL/6 mice. Western blot analysis of the serum samples showed an immune response to lipopolysaccharide, and the 30, 40 (major outer membrane protein) and 60 kDa cysteine-rich protein in both strains of mice. In addition, in the C3H mice a strong immune reaction was mounted against a 50 kDa component and the 60 kDa hsp. Six weeks after inoculation, the female mice were mated with male mice of proven fertility and the outcome of the pregnancies evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Induction of infertility by the Chlamydia trachomatis mouse pneumonitis biovar in strains of mice that differ in their response to the 60 kDa heat shock protein. 793 61

Female BALB/c mice were immunized intranasally with the mouse pneumonitis biovar of Chlamydia trachomatis and subsequently challenged in the ovarian bursa (C. trachomatis immunized, C. trachomatis challenged). Two groups of mice served as controls. One group was sham immunized intranasally with mock-infected HeLa 229 cell extracts and was challenged in the ovarian bursa with C. trachomatis MoPn (sham immunized, C. trachomatis challenged). The second control group was sham immunized and not challenged (sham immunized, nonchallenged). Before challenge, the C. trachomatis-immunized, C. trachomatis-challenged animals mounted a significant humoral response as shown by high immunoglobulin G (IgG), IgM, and IgA levels and high levels of neutralizing antibodies in serum and moderate IgG and IgA titers in vaginal secretions. Reactivity by Western blot (immunoblot) to the lipopolysaccharide, 30-, 40- (major outer membrane protein), and 60-kDa cysteine-rich proteins and 75- and 100-kDa chlamydial components could be demonstrated. However, reactivity to the 60-kDa heat shock protein was only observed 22 days after challenge. In addition, this group of animals mounted a significant immune response to chlamydial antigens, as shown by a lymphocyte proliferation assay, compared with the sham-immunized nonchallenged mice. After intrabursal challenge, there was no C. trachomatis shedding from the vagina in the C. trachomatis-immunized, C. trachomatis-challenged animals, while 63% of the sham-immunized, C. trachomatis-challenged mice had a positive C. trachomatis culture. In addition, histological sections from the genital tract showed, at 2 weeks postchallenge, a marked acute inflammatory reaction in the sham-immunized, C. trachomatis-challenged animals while in the C. trachomatis-immunized, C. trachomatis-challenged mice there was minimal inflammatory reaction. When the animals were mated, only 12% of the mice from the sham-immunized, C. trachomatis-challenged mice were fertile. In contrast, 94 and 80% of the sham-immunized, nonchallenged and C. trachomatis-immunized, C. trachomatis-challenged mice, respectively, were fertile.
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PMID:Protection against infertility in a BALB/c mouse salpingitis model by intranasal immunization with the mouse pneumonitis biovar of Chlamydia trachomatis. 803 6

Restriction fragments containing the major outer-membrane protein (MOMP) gene from two nonhuman (rodent) strains of Chlamydia trachomatis, the mouse pneumonitis (MoPn) strain and the SFPD strain isolated from hamsters with transmissible proliferative ileitis, were cloned and sequenced. The MOMP genes of both MoPn and SFPD encode an identical 22-amino acid leader peptide and mature polypeptides of 365 and 382 amino acids, respectively. Alignment of the MOMP genes of the two rodent strains revealed 91% identity. By comparison with other known chlamydial MOMP gene sequences, there was 80%-83% identity with human biovars strains of C. trachomatis, and there was 69%-70% identity with C. psittaci and C. pneumoniae strains. The main differences in these sequences were clustered into four variable domains. A minimum-length evolutionary tree was constructed on the basis of the MOMP gene variable positions by using PIMA package software. The minimum mutation distances indicated that (i) the MOMP genes of all chlamydial strains may have evolved from a common ancestor; (ii) all the strains of C. trachomatis compose one of the subtrees, and strains of C. psittaci and C. pneumoniae compose the other subtree; and (iii) in the C. trachomatis subtree, the human and the rodent strains are divided into two clusters. The branching pattern of this evolutionary tree is generally consistent with current classification based on serological, morphological, and other biological characteristics.
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PMID:Comparison of the major outer-membrane protein (MOMP) gene of mouse pneumonitis (MoPn) and hamster SFPD strains of Chlamydia trachomatis with other Chlamydia strains. 827 58

Legionella pneumophila, the causative agent of Legionnaires' disease is a facultative intracellular bacterium, which in the course of human infection multiplies in lung macrophages predominantly manifesting as pneumonia. The natural habitat of Legionella is found in sweet water reservoirs and man-made water systems. Virulent L. pneumophila spontaneously convert to an avirulent status at a high frequency. Genetic approaches have led to the identification of various L. pneumophila genes. The mip (macrophage infectivity potentiator) determinant remains at present the sole established virulence factor. The Mip protein exhibits activity of a peptidyl prolyl cis trans isomerase (PPIase), an enzyme which is able to bind the immunosuppressant FK506 and is involved in protein folding. The recently cloned major outer membrane protein (MOMP) could play a role in the uptake of legionellae by macrophages. Cellular models are useful in studying the intracellular replication of legionellae in eukaryotic cells. Human cell lines and protozoan models are appropriate for this purpose. By using U 937 macrophage-like cells and Acanthamoeba castellanii as hosts, we could discriminate virulent and avirulent L. pneumophila variants since only the virulent strain was capable of intracellular growth at 37 degrees C. By using these systems we further demonstrated that a hemolytic factor cloned and characterized in our laboratory, legiolysin (lly), had no influence on the intracellular growth of L. pneumophila.
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PMID:Analysis of virulence factors of Legionella pneumophila. 834 38

In immunoblot analysis, a murine monoclonal antibody (MAb), 27-1, which was produced to an outer membrane protein (OMP) of Haemophilus somnus, showed that a major OMP is heat modifiable, having a molecular mass of 28 kDa when the N-lauroylsarcosine-insoluble OMP preparation was solubilized at 60 degrees C and a mass of 37 kDa when the OMP preparation was solubilized at 100 degrees C. The heat-modifiable OMP reacted intensely with convalescent sera obtained from calves with experimental H. somnus pneumonia in immunoblot analysis. Immunoelectron microscopic and antibody absorption studies revealed that the MAb 27-1 epitope was not surface exposed on the intact bacterium. However, a decrease in antibody reactivity to the heat-modifiable OMP in immunoblot analysis after absorption of convalescent serum with intact bacterial cells of H. somnus suggests that a surface-exposed portion of the heat-modifiable OMP is expressed on the intact bacterium. MAb 27-1 reacted with 45 of 45 strains of H. somnus tested in immunoblot analysis. The apparent molecular mass of the antigen varied among strains, and five reactivity patterns demonstrated by MAb 27-1 were observed. MAb 27-1 also reacted with six species in the family Pasteurellaceae, Escherichia coli, and Salmonella dublin, but not with the other eight species of gram-negative bacteria. The heat-modifiable OMP of H. somnus showed immunological cross-reactivity with the OmpA protein of E. coli K-12 and significant N-terminal amino acid sequence homology with the OmpA proteins of gram-negative bacteria. We conclude that a major, 37-kDa heat-modifiable OMP of H. somnus, which elicits an antibody response in H. somnus-infected animals, is a common antigen among H. somnus strains tested and is structurally related to the OmpA protein of E. coli.
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PMID:Characterization of a heat-modifiable outer membrane protein of Haemophilus somnus. 847 64

Cell-mediated immune mechanisms may play a role in the pathogenesis and prevention of pneumonia in cattle caused by Pasteurella haemolytica serotype A1. To determine the circumstances required to stimulate and identify cell-mediated immune responses, calves were vaccinated with a commercial P. haemolytica bacterin or a live commercial P. haemolytica vaccine, or were infected intratracheally with virulent P. haemolytica. All calves were challenge-exposed intratracheally with P. haemolytica 31 d after vaccination or prior infection. Peripheral blood mononuclear cells and mediastinal and superficial cervical lymph node cells were stimulated with antigens prepared from P. haemolytica to evaluate in vitro proliferative responses and gamma-interferon production as measures of cell-mediated immunity. Strong proliferative responses and gamma-interferon production were detected in lymph node cells from calves vaccinated with the live vaccine and from infected calves, especially in response to stimulation with an outer membrane protein preparation from P. haemolytica. Greater proliferative responses and gamma-interferon production were associated with the lymph node nearer the site of bacterin administration (superficial cervical lymph node) or the site of infection (mediastinal lymph node), whereas greater proliferative responses and gamma-interferon production were associated with the more distant lymph node (mediastinal lymph node) in calves vaccinated with the live vaccine. Neither proliferative responses nor gamma-interferon production were detected in peripheral blood mononuclear cells from calves that were vaccinated for or infected with P. haemolytica. Antileukotoxin antibody titers were determined by a serum neutralization assay, and protection against pneumonic lesions was more closely correlated with antileukotoxin antibody responses than with lymphocyte proliferation or gamma-interferon responses.
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PMID:In vitro lymphocyte proliferative responses and gamma-interferon production as measures of cell-mediated immunity of cattle exposed to Pasteurella haemolytica. 890 62

In order to analyze the protective role that IgA may play in a chlamydial infection two IgA monoclonal antibodies (mAb), MoPn 4-2 and MoPn 13-2, were raised against the major outer membrane protein (MOMP) of the Chlamydia trachomatis mouse pneumonitis (MoPn) biovar. mAb MoPn 4-2 was found to be serovar specific while mAb MoPn 13-2 was species specific. mAb MoPn 4-2 recognized a surface exposed conformational epitope as shown by its ability to bind to native EBs and nonreduced MOMP while failing to bind to heat and trypsin treated EBs, to reduced MOMP and to synthetic MOMP peptides. In contrast, mAb MoPn 13-2 recognized a nonconformational epitope since it was able to bind treated EBs, to reduced MOMP and to the synthetic peptide MTTWNPTISGSGI located in variable domain 4 of the MOMP. Both mAbs agglutinated intact EBs and had in vitro neutralizing activity. However, mAb MoPn 4-2 had a 20-fold higher in vitro neutralizing ability when compared to mAb MoPn 13-2 (50% neutralization at 5 micrograms ml-1 vs 100 micrograms ml-1). In an in vitro in vivo infectivity assay, mAb MoPn 4-2 protected mice against infertility when C. trachomatis MoPn elementary bodies were preincubated with the mAb before inoculation. In addition, passive transfer of mAb MoPn 4-2 resulted in significant protection as measured by a decrease in the number of mice infected, and in the intensity and duration of vaginal shedding. These results support previous findings suggesting that IgA antibodies can play a role in protection against a chlamydial infection, and further encourage work to develop vaccination strategies that elicit mucosal immunity.
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PMID:Monoclonal immunoglobulin A antibody to the major outer membrane protein of the Chlamydia trachomatis mouse pneumonitis biovar protects mice against a chlamydial genital challenge. 916 May 28

The ability to induce protection against a genital challenge was studied in BALB/c female mice with three Chlamydia trachomatis mouse pneumonitis (MoPn) major outer membrane protein (MOMP) preparations as well as an acellular vaccine consisting of the chlamydial outer membrane complex (COMC). The MOMP preparations were extracted with three different types of detergents, sodium dodecyl sulfate (SDS), n-octyl-beta-D-glucopyranoside (OGP), and Zwittergent 3-14 (Z3-14). A positive immunization control consisted of mice inoculated intranasally with 10(4) C. trachomatis MoPn inclusion-forming units (IFU). Mice inoculated with ovalbumin served as a negative control. Furthermore, a sham-immunized, nonchallenged group was included as a fertility control. Two weeks after the last immunization, the mice were challenged in the left ovarian bursa with 10(5) C. trachomatis MoPn IFU. Vaginal swabs were collected for culture, vaginal and serum samples were assayed for chlamydial-specific antibodies, and splenocytes were collected to determine the lymphoproliferative response. At 42 days after the challenge, the mice were mated with proven male breeder mice. Animals that were considered to be pregnant (as determined by weight) were killed, and the embryos were counted. A significant humoral and cell-mediated immune response was observed in all the groups of mice inoculated with chlamydial antigens. Antibodies to variable domain (VD)1 of the MOMP were detected in serum samples from all the immunized groups. However, antibodies to VD3 and VD4 were detected only in the groups immunized with the Z3-14-MOMP and the COMC. Mice immunized with COMC developed significant immunoglobulin A chlamydia-specific antibodies in the vagina, while mice immunized with the detergent-extracted MOMPs had low antibody titers. Following the intrabursal challenge, a significant decrease in the intensity and duration of vaginal shedding was noted in the mice immunized with COMC and a moderate decrease was noted in the group immunized with OGP-MOMP. No protection against the infection was noted in the groups of animals immunized with SDS- and Z3-14-MOMP. Furthermore, of the mice immunized with the COMC preparation, only 25% (4 of 20) shed C. trachomatis, as determined by vaginal culture, while 83% (40 of 48) of the control mice inoculated with ovalbumin were culture positive (P < 0.05). In addition, after mating, the mice inoculated with COMC were found to have fertility rates comparable to those of the control sham-immunized, nonchallenged animals (70% [14 of 20] versus 81% [17 of 21], respectively [P > 0.05]), and there were no significant differences between the average number of embryos per mouse in the two groups (5.1 versus 5.9, respectively [P > 0.05]). In contrast, mice immunized with the purified MOMP preparations were not protected against infertility. In summary, a preparation of the COMC protected mice against infection and infertility, supporting the feasibility of the development of an acellular vaccine against C. trachomatis infections.
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PMID:Immunization with an acellular vaccine consisting of the outer membrane complex of Chlamydia trachomatis induces protection against a genital challenge. 923 98

Bovine IgG2a has been implicated in protection against pyogenic infections, including those caused by Haemophilus somnus. To further investigate the role of IgG2a in defense against H. somnus, IgG1 and IgG2a antibodies were purified from antiserum against an immunodominant 40 kDa outer membrane protein (p40) of H. somnus, which was previously shown to passively protect calves against H. somnus pneumonia. The passive protective capacity of anti-p40 IgG1 or IgG2a was evaluated in vivo in calves. Purified anti-p40 IgG1 or IgG2a was incubated with H. somnus for 15 min before intrabronchial inoculation of calves. Bacteria incubated with anti-p40 IgG1 or IgG2a were inoculated into one caudal lung lobe and bacteria incubated with IgG1 or IgG2a from the respective preimmunization serum were inoculated into the contralateral lobe. The volumes of pneumonia in the right and left lungs were determined 24 h later. The difference in volume of pneumonia with H. somnus preincubated in IgG1 pre- and postimmunization anti p40 was less (16 cm3, P = 0.298) than the difference in volume of pneumonia with H. somnus preincubated in IgG2a pre- and postimmunization anti p40 (30 cm3, P = 0.146). Although the differences in lesion size between pre- and postimmunization serum were not statistically significant, the trend suggests IgG2a may be more protective than IgG1. To examine this further, the peptide specificity of these IgG1 and IgG2a antibodies to p40 was examined. After limited proteolysis of p40, IgG2a antibodies reacted with 2 peptides not recognized by IgG1 antibodies. Other peptides were recognized by both isotypes. Since these studies suggested that IgG2a may be important in protection against infection, we then investigated some aspects of the role of the 2 IgG2a allotypes, A1 and A2. In retrospective studies of age differences in expression of IgG2a allotypes, no heterozygotes were detected in calves of 60 d old or less, and fewer heterozygotes were detected in calves 61-120 d old than in cattle older than 270 d (P < 0.01). In a subsequent prospective study of the time course of allotype expression, Holstein calves shown to be heterozygotes expressed the IgG2aA1 allotype early but the IgG2aA2 allotype was not usually detected until 3 to 4 mo of age. Thus, both the retrospective and the prospective studies showed age related differences in expression of the IgG2aA1 and A2 allotypes. This could have implication in protection.
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PMID:Bovine IgG2a antibodies to Haemophilus somnus and allotype expression. 924 1

The efficacy of DNA vaccination for prevention of Chlamydia trachomatis infection was studied using the murine model of pneumonia induced by the mouse pneumonitis (MoPn) isolate of C. trachomatis. Intramuscular DNA immunization with two chlamydial genes, one that encodes the major outer-membrane protein (MOMP) and one that encodes a cytoplasmic enzyme (cytosine triphosphate [CTP] synthetase) were tested. The MOMP DNA vaccine but not the CTP synthetase DNA vaccine generated significant delayed-type hypersensitivity and serum antibodies to MoPn elementary bodies and reduced the peak growth of MoPn by >100-fold following lung challenge infection. MOMP DNA immunization suggests a new approach to vaccine development for prevention of human chlamydial infection.
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PMID:DNA vaccination with the major outer-membrane protein gene induces acquired immunity to Chlamydia trachomatis (mouse pneumonitis) infection. 933 63


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