Assessment of the role in protection and pathogenesis of the Chlamydia muridarum V-type ATP synthase subunit A (AtpA) (TC0582).

A novel Chlamydia muridarum antigen (TC0582) was used to vaccinate BALB/c mice. Mice were also immunized with other components of the ATP synthase complex (TC0580, TC0581, and TC0584), or with the major outer membrane protein (MOMP). TC0582 was also formulated in combination with TC0580, TC0581 or MOMP. TC0582 alone, or in combination with the other antigens, elicited strong Chlamydia-specific humoral and cellular immune responses. Vaccinated animals were challenged intranasally and the course of the infection was followed for 10 days. Based on percentage change in body weight, lung weight, and number of Chlamydia inclusion forming units recovered from the lungs, mice immunized with TC0582, TC0581 or MOMP, as single antigens, showed significant protection. Mice immunized with combinations of two antigens were also protected but the level of protection was not additive. TC0582 has sequence homology with the eukaryotic ATP synthase subunit A (AtpA). Therefore, to determine if immunization with TC0582, or with Chlamydia, elicited antibodies that cross-reacted with the mouse AtpA, the two proteins were printed on a microarray. Sera from mice immunized with TC0582 and/or live Chlamydia, strongly reacted with TC0582 but did not recognize the mouse AtpA. In conclusion, TC0582 may be considered as a Chlamydia vaccine candidate.

Extraction of Chlamydia pneumoniae DNA from vascular tissue for use in PCR: an evaluation of four procedures.

The objective of this study was to compare four procedures for Chlamydia pneumoniae DNA extraction from vascular tissue. The NucliSens Kit, the QIAamp tissue DNA MiniKit, buffer-saturated phenol and the Geneclean II Kit were evaluated, based on the yield of recovered DNA, using PCR to detect C. pneumoniae in vascular tissue. The QIAamp tissue procedure had the highest detection level (0.004 inclusion-forming units/sample). All methods, except NucliSens (70 min), had a short handling time (30-40 min). Costs varied from 0.5 to 3.2 Euro.

The natural course of asymptomatic Chlamydia trachomatis infections: 45% clearance and no development of clinical PID after one-year follow-up.

The natural course of asymptomatic Chlamydia trachomatis infections in women was studied during one year in a cohort based nested case-control study. Healthy women (n = 744, from four company health services in Amsterdam) with a medical check-up prior to job engagement were included. C. trachomatis-positive women (n = 30, cases) and a randomly selected control group of C. trachomatis-negative women (n = 186, controls) were followed for one year. Urine specimens (at one, six and 12 months) were analysed for the presence of C. trachomatis-DNA and the C. trachomatis-serovars, and questionnaires were filled in. The C. trachomatis prevalence and natural course in relation to demographic and sexual characteristics after one, six and 12 months were studied. The main outcome measures were 1) the prevalence of C. trachomatis using urine specimens; 2) self-reported complaints; 3) clinical symptoms reported to the coordinating physicians. The prevalence of asymptomatic C. trachomatis infections was 4% and there was no correlation with demographic and sexual characteristics. The person/year clearance rate was 44.7% per year. None of the C. trachomatis-positive women developed clinical symptoms or used C. trachomatis specific antibiotic treatment. Women with or without an asymptomatic infection had the same number of self-reported urogenital complaints during follow-up. In persisting infections twice as many C. trachomatis-serovar E infections were detected as compared to clearing infections. Our findings showed that almost half of the asymptomatic C. trachomatis infections in women cleared during one year of follow-up and none developed clinical pelvic inflammatory disease (PID), which is a much lower figure than previously suggested. Therefore these data are important for cost effectiveness calculations in screening programmes for asymptomatic C. trachomatis infections.

ThinPrep pap test: a platform for gynecological diagnosis.

Many of the limitations of the conventional method of Pap smear preparation have been overcome by collection of the cervical sample in liquid, and subsequent preparation to create a thin-layer microscope slides. Particularly impressive has been the large body of literature that describes the benefits of the ThinPrep Pap Test, in terms of increased sensitivity of high-grade disease detection, excellent specificity, robust cost effectiveness, and a platform from which additional testing can be performed. The benefits of the ThinPrep are particularly evident in underscreened populations, or in women who are infrequently screened, or in the setting of a national program.

Effects of oral contraceptives in vaginal cytology.

Many literature studies have shown that long-term use of oral contraceptives (OC) is associated with lack of protection of the epithelium of the uterine cervix. Forty-five patients, from 18 to 35 years old, users of two contraceptive formulations, of different estrogenic concentration, took part in this study as volunteers to evaluate the predisposition of the cervix to pathologies. The results found before OC use were 11% of Chlamydia trachomatis infection and 13% of HPV infection. These pathologies were correctly treated and after 5 months of OC use we found total remission of Chlamydia trachomatis infection and 4% of persistent HPV infection. These data lead us to conclude that the OC studied here interfered very little with the presented pathologic results. The risk factors that we considered relevant were: 1) age group (the patients that presented HPV and C. trachomatis infections were young university students); 2) lifestyle (most patients certified that they did not combine the use of barrier contraceptives with the use of OC); 3) multiple sexual partners; 4) low socioeconomic condition.