Long-term stability of human genomic and human papillomavirus DNA stored in BD SurePath and Hologic PreservCyt liquid-based cytology media.

We evaluated the effect of storage at 2 to 8°C on the stability of human genomic and human papillomavirus (HPV) DNA stored in BD SurePath and Hologic PreservCyt liquid-based cytology media. DNA retained the ability to be extracted and PCR amplified for more than 2.5 years in both medium types. Prior inability to detect DNA in archived specimens may have been due to failure of the extraction method to isolate DNA from fixed cells.

Comparison of self-obtained penile-meatal swabs to urine for the detection of C. trachomatis, N. gonorrhoeae and T. vaginalis.

BACKGROUND: Self-obtained penile-meatal swabs and urine specimens have been used for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) for outreach screening in men. OBJECTIVE: To compare the sensitivity of self-collected male penile-meatal swabs and urine for the detection of CT, NG and TV. METHODS: Matching penile-meatal swabs and urines were collected at home after recruitment to the study; via the internet programme, http://www.iwantthekit.org. The instructions directed the participant to place the tip of a Copan flocked swab at the meatal opening of the urethra to collect the penile-meatal sample. Two ml of urine was collected after the swab onto a Copan sponge-on-a-shaft collection device. Both swab and urine were placed into individual Aptima transport media tubes and mailed to the laboratory for testing. All specimens were tested for CT and NG using the GenProbe Aptima Combo2 Assay and for TV using GenProbe Aptima Analyte Specific Reagents with TV oligonucleotides. RESULTS: Of 634 men, 86 (13.6%) were positive for CT, 9 (1.4%) were positive for NG and 56 (9.3%) positive for TV. For CT, swab sensitivity was 81/86 (94.2%), and urine sensitivity was 66/86 (76.7%). For NG, swab sensitivity was 9/9 (100%) and urine sensitivity was 8/9 (88.9%). For TV, swab sensitivity was 45/56 (80.4%) and urine sensitivity was 22/56 (39.3%). CONCLUSIONS: Self-obtained penile-meatal swabs provided for the detection of more CT, NG and TV, than urine specimens.

Trichomonas vaginalis infection in women who submit self-obtained vaginal samples after internet recruitment.

BACKGROUND: Submission of self-obtained vaginal samples (SOVs) collected at home could remove barriers that women face in getting tested for sexually transmitted infections (STIs). Internet recruitment of SOVs is highly acceptable. METHODS: Sexually active women ≥14 years were recruited by an educational Internet program, available at: www.iwantthekit.org (IWTK), which offered free testing for trichomonas as part of a panel, which also offered testing for chlamydia and gonorrhea. Kits were ordered online, SOVs were sent through US mail to the laboratory, and tested by nucleic acid amplification tests. Demographics and sexual risk factors were accessed by questionnaires. Women called or were contacted to receive their results. RESULTS: Of women requesting kits, 1525 (43%) returned swabs by mail. In all, 61% were <25 years, 52% were black, and 80% were single. Vaginal discharge was reported by 44%, prevalence for trichomonas was 10% (10% for chlamydia, 1% for gonorrhea), and 18% had at least one prevalent STI. Multivariate logistic regression demonstrated several significantly associated risks factors as follows: adjusted odds ratio for black race was 2.69; for residence of Illinois, 3.85; for not having health insurance, 1.57; for lack of a bachelor's degree, 5.53; for having 2 to 15 partners, 1.60; for having ≥16 partners in previous year, 3.51; for being bisexual, 2.0; for not always using condoms, 3.04; and for having a partner who had a previous STI, 1.71. Age was not associated with trichomonas infection. All infected women were treated. CONCLUSIONS: A high prevalence of trichomonas and high sexual risk factors were demonstrated. Internet recruitment was a useful method of screening women for trichomonas infection.

Chlamydia trachomatis age-specific prevalence in women who used an internet-based self-screening program compared to women who were screened in family planning clinics.

OBJECTIVES: To determine whether women who collect self-collected vaginal swabs at home demonstrated a higher positivity of Chlamydia trachomatis than women in family planning clinics. METHODS: Collection kits for vaginal swabs were internet requested, collected at home, and mailed to a laboratory for testing; questionnaires were completed about acceptability and sexual risk history. Infected women received treatment at participating clinics. Age-specific prevalences were compared to those from family planning clinics. RESULTS: Chlamydia positivity was 10.3% for 1171 females mailing swabs; prevalences ranged from 3.3% to 5.5% in family planning. Positivity for internet age groups was much higher than those for family planning age groups. The positivity for internet participants ranged from a low of 4.4% in Baltimore in 2005 to a high of 15.2% Baltimore in 2007. Family planning clinic prevalence in Baltimore and Maryland ranged from a low of 3.3% in Baltimore in 2006 to a high of 5.5% in Baltimore in 2008. The median age for all years for internet users in Baltimore and Maryland combined was 23 years; the median age for all years for attendees to family planning clinics who had chlamydia testing performed was 23 years. CONCLUSIONS: Internet recruited women demonstrated higher positivity of chlamydia than those in family planning, providing new options for chlamydia screening programs.

Will patients "opt in" to perform their own rapid HIV test in the emergency department?

OBJECTIVE: We evaluate the feasibility and accuracy of existing point-of-care HIV tests performed by an untrained patient compared with the routinely used HIV point-of-care test offered to patients in 2 urban emergency departments (EDs). METHODS: From April 2008 through December 2009, patients who had completed a standard HIV oral fluid test performed by a trained health care professional and who were unaware of their results were recruited to perform a rapid point-of-care HIV test. Patients were given a choice of the oral fluid or the fingerstick blood point-of-care test. Evaluation of acceptability to perform the mechanics of the test was accessed by questionnaire. For the "self-test," the participant obtained his or her own sample and performed the test. The patient's results were compared with standard oral fluid results obtained by the health care professional. RESULTS: Overall, 478 of 564 (85%) patients receiving a standard oral fluid HIV test volunteered, with a mean age of 38 to 39 years. Ninety-one percent of participants chose oral fluid and 9% chose blood (P<.05). Self-test results were 99.6% concordant with health care professionals' test results. For the self-testers, 94% of oral fluid testers and 84.4% of blood testers reported trusting the self-administered test result "very much." Furthermore, 95.6% of the oral fluid group and 93.3% of the blood group would "probably" or "definitely" perform a test at home, if available. CONCLUSION: This study demonstrated that a significant proportion of patients offered a self-HIV point-of-care test volunteered and preferred using oral fluid. Patients' results agreed with standard HIV point-of-care results. The majority of participants trusted their results and would perform a point-of-care HIV test at home, given the opportunity.

The role for T cell repertoire/antigen-specific interactions in experimental kidney ischemia reperfusion injury.

T cells have been implicated in the early pathogenesis of ischemia reperfusion injury (IRI) of kidney, liver, lung, and brain. It is not known whether Ag-TCR engagement followed by Ag-specific T cell activation participates in IRI. T cell-deficient nu/nu mice are moderately resistant to renal IRI, which can be reversed upon reconstitution with syngeneic T cells. In this study, we found that nu/nu mice reconstituted with DO11.10 T cells, limited in their TCR repertoire, have significantly less kidney dysfunction and tubular injury after renal IRI compared with that in nu/nu mice reconstituted with wild-type T cells having a diverse TCR repertoire. CD4(+) T cells infiltrating ischemic kidneys of nu/nu mice reconstituted with DO11.10 T cells exhibited lower IFN-gamma production than that of wild-type controls. Frequency of regulatory T cells in kidneys of these mice was similar in both DO11.10 T cells and wild-type T cell recipient groups. DO11.10 mice immunized with OVA-CFA had significantly worse kidney function at 24 h after ischemia than those immunized with CFA alone. Thus, without T cell activation, diverse TCR repertoire was important for renal IRI in naive mice. However, once T cells were activated in an Ag-specific manner through TCR in DO11.10 mice, a restricted TCR repertoire no longer limited the extent of kidney injury. Thus, both TCR repertoire-dependent and -independent factors mediate T cell functions in kidney IRI.

Adolescent women can perform a point-of-care test for trichomoniasis as accurately as clinicians.

OBJECTIVES: To compare the accuracy (ie, correlation, sensitivity, specificity) of self-performed point-of-care (POC) tests with clinician-performed tests for trichomoniasis in adolescent women. METHODS: Sexually experienced women aged 14-22 years (n=209) collected a vaginal swab and performed a POC test for trichomoniasis. Using a speculum, the clinician obtained vaginal swabs that were tested for trichomoniasis using the POC test, wet mount, culture and transcription-mediated amplification (TMA) using standard and alternative primers. Self and clinician results were compared with true positives, defined as either culture-positive or TMA-positive with both sets of primers. RESULTS: Participants' mean age was 17.8 years; 87% were African-American; 74% reported vaginal itching or discharge and 51 (24%) had trichomoniasis. Over 99% correctly performed and interpreted her self-test. Self and clinician POC tests were highly correlated (95.7% agreement, κ 0.87). Compared with true positives, the sensitivity of the self-POC test was 78% (CI 65% to 89%), similar to that of the clinician-POC test (84%, CI 71% to 93%) and culture (82%, CI 69% to 92%), and significantly better than wet mount (39%, CI 26% to 54%). The specificity of the self-POC test was 99% (CI 96% to 100%), similar to that of the clinician-POC test (100%, CI 98% to 100%). The sensitivity of the self-POC test was not affected by vaginal symptoms or other variables. CONCLUSIONS: Young women performing a self-POC test detected as many trichomoniasis infections as clinician-POC tests or culture, twice as many as wet mount and slightly fewer than an amplified test. Incorporating self-obtained or self-performed POC tests into routine practice could effectively increase the identification and treatment of trichomoniasis in this vulnerable population.

Internet-based screening for sexually transmitted infections to reach nonclinic populations in the community: risk factors for infection in men.

BACKGROUND: Internet-based screening for sexually transmitted infections (STIs) has been acceptable to women, and can reach high-risk populations. No prior published data describe internet-based screening for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis in men. We studied whether internet-based screening was acceptable and reached a high-risk population, and what risk factors were associated with STI positivity. METHODS: The website, www.iwantthekit.org, encouraged men ≥14 years of age to request a home self-sampling kit and a questionnaire on risk factors and acceptability of internet-based screening. Penile swabs and urine samples were tested for C. trachomatis, N. gonorrhoeae, and T. vaginalis using a nucleic acid amplification test. Risk factors and acceptability were examined using chi squared tests and logistic regression. RESULTS: Of 501 samples received for testing, 106 (21%) were positive for at least one STI, 64 (13%) for chlamydia, 4 (1%) for gonorrhea, and 49 (10%) for trichomonas. In multivariable analyses, age, race, household income, and frequency of condom use were independently associated with infection with at least one STI. Of the total respondents, 34% had a prior STI; 29% reported having a partner with an STI, but only 13% reported always using a condom. Among the men who participated in this study, 77% preferred a self-administered specimen versus attending a clinic, 89% reported that swab use was easy, and 89% reported that they would use internet-based screening again. CONCLUSIONS: Men who accessed internet-based screening had known risk factors for STIs and had a high prevalence of infection. Internet-based screening was acceptable and could reach these high-risk men who might not otherwise be reached through traditional means.

Foxp3+ regulatory T cells participate in repair of ischemic acute kidney injury.

T lymphocytes modulate early ischemia-reperfusion injury in the kidney; however, their role during repair is unknown. We studied the role of TCRbeta(+)CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs), known to blunt immune responses, in repair after ischemia-reperfusion injury to the kidney. Using a murine model of ischemic acute kidney injury we found that there was a significant trafficking of Tregs into the kidneys after 3 and 10 days. Post-ischemic kidneys had increased numbers of TCRbeta(+)CD4(+) and TCRbeta(+)CD8(+) T cells with enhanced pro-inflammatory cytokine production. Treg depletion starting 1 day after ischemic injury using anti-CD25 antibodies increased renal tubular damage, reduced tubular proliferation at both time points, enhanced infiltrating T lymphocyte cytokine production at 3 days and TNF-alpha generation by TCRbeta(+)CD4(+) T cells at 10 days. In separate mice, infusion of CD4(+)CD25(+) Tregs 1 day after initial injury reduced INF-gamma production by TCRbeta(+)CD4(+) T cells at 3 days, improved repair and reduced cytokine generation at 10 days. Treg manipulation had minimal effect on neutrophil and macrophage infiltration; Treg depletion worsened mortality and serum creatinine, while Treg infusion had a late beneficial effect on serum creatinine in bilateral ischemia. Our study demonstrates that Tregs infiltrate ischemic-reperfused kidneys during the healing process promoting repair, likely through modulation of pro-inflammatory cytokine production of other T cell subsets. Treg targeting could be a novel therapeutic approach to enhance recovery from ischemic acute kidney injury.

Performance of three nucleic acid amplification tests for detection of Chlamydia trachomatis and Neisseria gonorrhoeae by use of self-collected vaginal swabs obtained via an Internet-based screening program.

Use of self-obtained vaginal specimens processed by nucleic acid amplification tests (NAATs) has significantly increased the utilization of nontraditional locations for Chlamydia trachomatis and Neisseria gonorrhoeae screening programs. One important emerging source of such venues includes home-based self-sampling kits available via the Internet. The objective of our study was to evaluate the performance of three commercially available NAATs (Becton-Dickinson ProbeTec SDA, Gen-Probe Aptima Combo2 TMA, and Roche Amplicor PCR) for detection of C. trachomatis and N. gonorrhoeae in vaginal samples obtained via an Internet-based screening program. From July 2004 to August 2005, 500 self-collected vaginal swabs were tested for C. trachomatis and N. gonorrhoeae by using all three NAATs. Another 500 samples were collected between August 2005 and November 2007 and tested by ProbeTec and Combo2; PCR testing was discontinued due to low specificity for N. gonorrhoeae. All tests were conducted according to the manufacturers' procedures; the "gold standard" for an infected C. trachomatis or N. gonorrhoeae patient was defined as > or = 2 positive NAAT results. Of the first 500 swabs submitted, 46 were C. trachomatis infected (9.2%) and 5 were N. gonorrhoeae infected (1.0%), and 3 of these were coinfected (0.6%). All C. trachomatis and N. gonorrhoeae Combo2-positive/ProbeTec-negative samples were confirmed as true positives by an alternative NAAT. For C. trachomatis, ProbeTec, Combo2, and PCR had sensitivities of 82.6%, 100%, and 100%, with specificities of 100%, 100%, and 99.3%, respectively. For N. gonorrhoeae, ProbeTec, Combo2, and PCR had sensitivities of 80%, 100%, and 100%, with specificities of 100%, 100%, and 98.8%, respectively. Of the total 1,000 swabs submitted, 92 were C. trachomatis infected (9.2%) and 15 were N. gonorrhoeae infected (1.5%), and 7 of these were coinfected (0.7%). There were no ProbeTec-positive/Combo2-negative samples. For C. trachomatis, ProbeTec and Combo2 had sensitivities of 81.5% and 100%, with specificities of 100% and 100%, respectively. For N. gonorrhoeae, ProbeTec and Combo2 had sensitivities of 80% and 100%, with specificities of 100% and 100%, respectively. Overall, ProbeTec had 17 C. trachomatis false-negative results (1.7%) and 3 N. gonorrhoeae false-negative results (0.3%), while Combo2 had none. Our results were consistent with the sensitivities and specificities stated by the manufacturers. NAATs perform well for detection of chlamydia and gonorrhea with self-obtained vaginal swabs shipped in a dry state to a laboratory. For 1,000 self-collected vaginal swabs tested by NAATs, the sensitivities for C. trachomatis and N. gonorrhoeae for Combo2 were 100% and 100%, while they were 81.5% and 80%, respectively, for ProbeTec. For 500 PCR samples, the C. trachomatis sensitivity was 100% and the N. gonorrhoeae sensitivity was 100%, with specificities of 99.3% and 98.8%, respectively.

Clinical performance of the BD Onclarity HPV assay using an adjudicated cohort of BD SurePath liquid-based cytology specimens.

OBJECTIVES: To compare the performance of the BD Onclarity HPV Assay (BD Diagnostics, Sparks, MD) in BD SurePath liquid-based cytology media with that of Hybrid Capture 2 (HC2, Qiagen, Germantown, MD) samples co-collected in specimen transport medium in an adjudicated patient cohort. METHODS: The performance of the BD Onclarity HPV Assay using BD SurePath media was compared with that of HC2 samples co-collected in specimen transport medium using 541 archived samples from a multicenter US clinical trial with histologically adjudicated cervical biopsy specimens. RESULTS: The sensitivity for cervical intraepithelial neoplasia (CIN) 2 positivity (n - 104) was 90.4% (95% confidence interval [CI], 83-95) and 93.3% (95% CI, 87-97) and specificity was 76.9% (95% CI, 73-81) and 77.8% (95% CI, 74-82) for the BD assay and HC2, respectively. Nine cases of CIN 2+ had results discordant with the high-risk HPV assay. All were found to have been correctly classified with the BD assay using a novel WAVE denaturing high-performance liquid chromatography double-stranded DNA sequencing method. CONCLUSIONS: The clinical performance of The BD Onclarity HPV Assay with respect to histology end points was similar to HC2. Moreover, discordant analysis revealed improved performance of the BD assay with respect to ability to provide extended genotyping information and lack of cross-reactivity with low-risk HPV types associated with cellular abnormalities. The relative risks for CIN 3 disease for HPV 31 and HPV 33/58 (combined) were comparable to that of HPV 18 in this population, suggesting that these genotypes may warrant monitoring in future studies.

Can mailed swab samples be dry-shipped for the detection of Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis by nucleic acid amplification tests?

Dry-shipped and mailed vaginal swabs collected at home have been used in research studies for the detection of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (GC), and Trichomonas vaginalis (TV) by nucleic acid amplification tests (NAATs) in screening programs. A verification study was performed to compare the limit of detection of CT, GC, and TV on swabs that were dry-shipped to paired swabs that were wet-shipped in transport media through the US mail. The Centers for Disease Control and Prevention prepared inocula in sterile water to mock simulated urogenital swabs with high to low concentrations of CT and GC. Replicate swabs were inoculated with 100 µL of dilutions and were dry transported or placed into commercial transport media ("wet") for mailing for NAAT testing. The University of Alabama prepared replicate concentrations of TV, which were similarly shipped and tested by NAAT. All paired dry and wet swabs were detectable for CT. For GC, all paired dry and wet swabs were detectable for GC at concentrations ≥ 10(3). At 10(2) and 10 CFU/mL, the 10 replicate GC results were variably positive. For TV, wet and dry shipped concentrations >10(2) TV/mL tested positive, while results at 10 TV/mL were negative for dry swabs. Holding replicate dry swabs at 55 (○)C 5 days before testing did not affect results. NAATs were able to detect CT, GC, and TV on dry transported swabs. Using NAATs for testing home-collected, urogenital swabs mailed in a dry state to a laboratory may be useful for outreach screening programs.

Use of the internet and self-collected samples as a sexually transmissible infection intervention in rural Illinois communities.

BACKGROUND: In the USA, reported cases of chlamydia (Chlamydia trachomatis) continue to rise despite substantial funding for screening. National gonorrhoea (Neisseria gonorrhoeae) rates have remained relatively stable, with clusters associated with metropolitan areas. Rural areas are no exception, as every county in Illinois reported cases of chlamydia in 2007. Morbidity associated with infection remains a public health concern, with costs of $US2.5+ billion annually. Novel screening interventions must be examined for their ability to reach those at risk who are missed by traditional methods. METHODS: The website Iwantthekit.org was modified to allow residents from 25 contiguous counties in Central Illinois to request a self-collected sample kit. Returned kits were tested for chlamydia and gonorrhoea. The initial study period was 12 months. RESULTS: During the study period, 343 kits were requested from 20 counties and 39.9% were satisfactorily returned for analysis. Positivity rates for chlamydia and gonorrhoea were 5.8% and 1.2%, respectively, for females and 1.9% and 0% for males. Males comprised 37.7% of all internet samples (compared with 23.4% for traditional screening venues) and 40.4% of all internet samples submitted by whites (compared with only 17.2% of traditional screening). CONCLUSIONS: The female positivity rate was comparable to those seen in other screening venues and the method successfully engaged at-risk males. Overall, participation was low and the costs associated with the program outweighed the averted costs associated with the few cases identified. While this methodology resulted in sample requests from a wide area, it must be utilised by more individuals to become cost-effective.

Development of a microwave-accelerated metal-enhanced fluorescence 40 second, <100 cfu/ml point of care assay for the detection of Chlamydia trachomatis.

An inexpensive technology to both lyse Chlamydia trachomatis (CT) and detect DNA released from CT within 40 s is demonstrated. In a microwave cavity, energy is highly focused using 100-nm gold films with "bow-tie" structures to lyse CT within 10 s. The ultrafast detection of the released DNA from less than 100 cfu/mL CT is accomplished in an additional 30 s by employing the microwave-accelerated metal-enhanced fluorescence technique. This new "release and detect" platform technology is a highly attractive alternative method for the lysing of bacteria, DNA extraction, and the fast quantification of bacteria and potentially other pathogenic species and cells as well. Our approach is a significant step forward for the development of a point of care test for CT.

Mycophenolate mofetil modifies kidney tubular injury and Foxp3+ regulatory T cell trafficking during recovery from experimental ischemia-reperfusion.

Lymphocytes participate in the early pathogenesis of ischemia-reperfusion injury (IRI) in kidney; however, their role during repair is largely unknown. Recent data have shown that Foxp3(+) regulatory T cells (Tregs) traffic into kidney during healing from IRI and directly participate in repair. Since lymphocyte-targeting therapy is currently administered to prevent rejection during recovery from IRI in renal transplants, we hypothesized that mycophenolate mofetil (MMF) would alter Treg trafficking and kidney repair. C57BL/6J and T cell deficient mice underwent unilateral clamping of renal pedicle for 45 min, followed by reperfusion, and were sacrificed at day 10. Mice were treated with saline (C) or MMF (100mg/kg) i.p. daily starting at day 2 until sacrifice (n=5-12/group). MMF worsened kidney tubular damage compared to C at 10 days (cortex and outer medulla: p<0.05) in wild-type mice; tubular apoptotic index was increased in cortex in MMF group as well (p=0.01). MMF reduced the total number of kidney-infiltrating mononuclear cells (p<0.001 versus C) and the percentages of TCRbeta(+)CD4(+) and TCRbeta(+)CD8(+) T cells (p<0.01), but not natural killer (NK), NKT or B lymphocytes. MMF specifically reduced kidney Foxp3(+) Tregs (0.82+/-0.11% versus 1.75+/-0.17%, p<0.05). Tubular proliferative index and tissue levels of basic FGF were increased in MMF group (p<0.05), IL-10 and IL-6 were decreased (p<0.05). To evaluate if MMF effect occurred through non-lymphocytic cells, T cell deficient mice were treated with MMF. Tubular injury in T cell deficient mice was not affected by MMF treatment, though MMF-treated animals had increased VEGF and decreased PDGF-BB protein tissue levels compared to controls (p<0.05). Thus, MMF modifies the structural, epithelial proliferative and inflammatory response during healing, likely through effects on T cells and possibly Tregs. Kidney repair after IRI can be altered by agents that target lymphocytes.

Chlamydia pneumoniae infection and risk for lung cancer.

BACKGROUND: We evaluated the relationship of Chlamydia pneumoniae infection with prospective lung cancer risk using traditional serologic markers [microimmunoflourescence (MIF) IgG and IgA antibodies] and Chlamydia heat shock protein-60 (CHSP-60) antibodies, a marker for chronic chlamydial infection. METHODS: We conducted a nested case-control study (593 lung cancers and 671 controls) within the screening arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (N = 77,464). Controls were matched to cases by age, sex, randomization year, follow-up time, and smoking (pack-years of smoking, time since quitting). We assessed C. pneumoniae seropositivity and endpoint antibody titers (IgG and IgA against C. pneumoniae elementary bodies and IgG against CHSP-60). RESULTS: C. pneumoniae seropositivity by microimmunoflourescence IgG or IgA antibodies was not associated with lung cancer [odds ratio of 0.88 and 95% confidence interval (95% CI) of 0.69-1.13 for IgG; odds ratio of 0.98 and 95% CI of 0.75-1.27 for IgA]. In contrast, individuals seropositive for CHSP-60 IgG antibodies had significantly increased lung cancer risk (odds ratio, 1.30; 95% CI, 1.02-1.67), and risk increased with increasing antibody titers (P trend = 0.006). CHSP-60-related risk did not differ significantly by lung cancer histology, follow-up time, or smoking. CHSP-60 seropositivity was associated with increased risk 2 to 5 years before lung cancer diagnosis (odds ratio, 1.77; 95% CI, 1.16-2.71; P trend = 0.006), thus arguing against reverse causality. CONCLUSIONS: CHSP-60 seropositivity and elevated antibody titers were associated with significantly increased risk for subsequent lung cancer, supporting an etiologic role for C. pneumoniae infection in lung carcinogenesis. IMPACT: Our results highlight the potential for lung cancer risk reduction through treatments targeted toward C. pneumoniae infections and chronic pulmonary inflammation.