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R W Peeling

Publications and source records attributed to R W Peeling.

58 records · Page 4Linked to original sources

High-resolution 31P nuclear magnetic resonance study of Chlamydia trachomatis: induction of ATPase activity in elementary bodies.

ATPase activity of elementary bodies (EBs) of Chlamydia trachomatis was investigated by using high-resolution 31P nuclear magnetic resonance spectroscopy. ATPase activity was detected in EBs of C. trachomatis serovars A, B, and L2 after treatment with the reducing agents 2-mercaptoethanol and glutathione. ATPase activity was oligomycin sensitive and magnesium ion dependent. EBs heated at 60 degrees C for 10 min or pretreated with Triton X-100 before exposure to 2-mercaptoethanol did not exhibit ATPase activity. Monoclonal antibody to the major outer membrane protein abrogated ATPase activity of EBs, whereas monoclonal antibody to chlamydial lipopolysaccharide only marginally reduced the level of ATPase activity. These findings suggest that EBs possess intrinsic ATPase activity and that cysteine-rich outer membrane proteins of EBs are important in the regulation of ATPase activity. The major outer membrane protein may be the major route through which ATP accesses ATPase.

Adenosine Triphosphatases↗

Characterization of Chlamydia trachomatis antigens with monoclonal and polyclonal antibodies.

We used monoclonal antibodies (MAbs) to examine the antigenic specificity and biologic function of several Chlamydia trachomatis antigens. Thirteen distinct MAbs to eight C. trachomatis antigens were produced. Six MAbs reacted with unique epitopes on the major outer membrane protein (MOMP) and two of these had neutralizing activity. MAbs were produced to each of the chlamydial antigens with molecular masses of 10, 29, 32, 57, 60, 70, and 75 kilodaltons (kDa). These MAbs showed species and genus specificity in an immunoblot assay. None of the MAbs had neutralizing activity. The epitopes recognized on MOMP, 29-, and 10-kDa (presumably lipopolysaccharide) antigens were surface exposed. MAbs to the 75-kDa, 57-kDa, and MOMP antigens were used for immunoaffinity purification of these antigens to produce monospecific antisera in mice. With polyclonal sera, we found that the 75-kDa antigen was also immunoaccessible and that antibody to MOMP and 75-kDa antigens neutralized C. trachomatis infectivity. We conclude that, in addition to MOMP and lipopolysaccharide, antigens with molecular masses of 75 and 29 kDa are surface exposed. Antibodies to MOMP and 75-kDa antigens can neutralize the organism in vitro.

Animals↗

Chlamydia trachomatis: its role in tubal infertility.

We compared the prevalence of antibody to Chlamydia trachomatis among 88 women undergoing an evaluation for infertility and 49 women attending an antenatal clinic. Demographic data regarding sexual behavior were also collected. Eighteen women had tubal infertility and 70 had infertility due to a variety of other reasons. In comparison with women who had other causes for infertility, women with tubal infertility began coitus sooner (17.7 +/- 2.2 years vs. 19.5 +/- 3.4 years, P less than .05) and had more lifetime sex partners (4.5 vs. 1.33, P less than .001). Women with tubal infertility had a higher prevalence of antibody to C. trachomatis (13 of 18) than did women with nontubal causes for infertility (6 of 70, P less than .0001) or pregnant women (11 of 49, P = .0003). This high prevalence of antibody to C. trachomatis among women with tubal infertility was independent of sexual experience. By immunoblot analysis, an antigen of approximately 57,000 Da was immunodominant in 11 of 13 seropositive subjects with tubal infertility vs. 2 of 6 seropositive subjects with nontubal infertility (P = .046) and 1 of 11 seropositive pregnant women (P = .0003). Thus, women with tubal infertility frequently have serological evidence of prior infection with C. trachomatis and have a distinctive antigen-specific humoral immune response. These results further support the etiologic role of infection with C. trachomatis in tubal infertility.

Antibodies, Bacterial↗

Chlamydiae as pathogens: new species and new issues.

The recognition of genital chlamydial infection as an important public health problem was made first by the recognition of its role in acute clinical syndromes, as well as in serious reproductive and ocular complications, and secondly by our awareness of its prevalence when diagnostic tests became widely accessible. The recent availability of effective single dose oral antimicrobial therapy and sensitive molecular amplification tests that allow the use of noninvasive specimens for diagnosis and screening is expected to have a major impact in reducing the prevalence of disease in the next decade. Clinical manifestations associated with Chlamydia pneumoniae infection continue to emerge beyond respiratory illness. In particular, its association with atherosclerosis deserves further investigation. Chlamydia pecorum, a pathogen of ruminants, was recently recognized as a new species. The continued application of molecular techniques will likely elucidate an expanding role for chlamydiae in human and animal diseases, delineate the phylogenetic relationships among chlamydial species and within the eubacteria domain, and provide tools for detection and control of chlamydial infections.

Anti-Bacterial Agents↗