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C M Wheeler

Publications and source records attributed to C M Wheeler.

At least 37 records · Page 2Linked to original sources
PubMed1996

Intratype variation in 12 human papillomavirus types: a worldwide perspective.

In this study, we have examined intratype human papillomavirus (HPV) sequence variation in a worldwide collection of cervical specimens. Twelve different HPV types including HPV-18, HPV-33, HPV-35, HPV-39, HPV-45, HPV-51, HPV-52, HPV-58, HPV-59, HPV-68 (ME180), MM9/PAP238A (recently designated HPV-73), and a novel partial genomic HPV sequence designated MM4/Wl3B were analyzed in this study. Cervical specimens were collected as part of epidemiological investigations conducted in New Mexico and an international study of invasive cervical cancer (IBSCC). Specimens from several countries including Argentina, Brazil, Bolivia, Benin, Cuba, Colombia, Chile, Germany, Mali, Panama, Paraguay, Spain, Algeria, Uganda, Guinea, Tanzania, Indonesia, Philippines, Thailand, and the United States were evaluated. Specimen DNAs were subjected to amplification with the MY09/11 L1 consensus PCR system. The PCR products were cloned, and an approximately 410-bp region in the L1 open reading frame was sequenced from 146 specimens (approximately 60,000 bp). Within a single HPV type, nucleotide diversity varied between 0.2 and 2.9% (i.e., between any pair of variants) and the majority of nucleotide changes were synonymous (amino acid conserving). These data provide information pertinent to HPV diagnostic probe development and are potentially relevant to future rational vaccine strategies. Similarly, amino acid diversity varied between 0 and 5.1%. Some of these amino acid changes may represent markers of intertype evolutionary relationships. Presuming that HPVs have evolved under the same constraints as their corresponding hosts, the limited genetic diversity observed for all HPVs studied to date may reflect an evolutionary bottleneck occurring in both virus and host populations.

Amino Acid Sequence↗
PubMed1995

Comparison of human leukocyte antigen DR-DQ disease associations found with cervical dysplasia and invasive cervical carcinoma.

BACKGROUND: Human leukocyte antigen (HLA) molecules, whose biological role is in the regulation of immune responses to foreign antigens and in discrimination of self from non-self antigens, are encoded by a series of closely linked genetic loci found on chromosome 6. Although the evidence for a link between HLA and cervical cancer has been controversial, it has been recently reported that certain HLA class II haplotypes (linked class II alleles) are positively associated with invasive cervical cancer, while other class II haplotypes are negatively associated or protective. Since HLA associations between human papillomavirus type 16 (HPV16)-mediated cancer cases and non-HPV16-mediated cancer cases have been found to be different, this suggests that specific HLA class II haplotypes may influence the immune response to HPV infection and may affect the risk of acquiring invasive cervical carcinoma. PURPOSE: This study was conducted to determine if the same HLA class II haplotypes that are associated with invasive cervical carcinoma are also associated with cervical dysplasia (presumed precursors of invasive cervical cancer). METHODS: We have examined HLA DR-DQ haplotypes among 128 Hispanic women from New Mexico with biopsy-confirmed cervical dysplasia in a case-control study using sensitive DNA-based polymerase chain reaction amplification and sequence-specific oligonucleotide probe hybridization methods to detect the presence and type of HPV and to detect allelic polymorphism in the HLA DRB1 and DQB1 loci. RESULTS: Dysplasia cases were divided into two groups for comparison to controls: severe dysplasia/carcinoma in situ (CIS), and slight/moderate dysplasia. The frequency distribution of HLA class II haplotypes among the HPV16-positive severe dysplasia/CIS cases had a statistically significant (two-tailed P < .005) difference compared with controls, whereas haplotypes among the severe dysplasia/CIS cases containing HPV types other than HPV16 did not show statistically significant frequency differences. DR-DQ haplotypes previously found to be associated with HPV16-invasive cervical carcinomas were also associated with HPV16-positive severe dysplasia/CIS. However, no statistically significant haplotype frequency difference was observed between slight/moderate dysplasia cases and controls. In addition, we noted a DQA1-DQB1 haplotype negatively associated with severe dysplasia/CIS but not with invasive cervical cancers. CONCLUSIONS: Our results strongly suggest that certain HLA haplotypes confer an increased risk for severe cervical dysplasia and invasive cervical carcinoma following HPV16 infection. IMPLICATIONS: Further molecular studies are needed to identify HLA alleles or haplotypes that may provide increased susceptibility to HPV-associated cervical disease.

Adult↗
PubMed1995

Generation of entire human papillomavirus genomes by long PCR: frequency of errors produced during amplification.

Recently, several improvements of traditional PCR techniques have facilitated the amplification of significantly longer DNA target sequences. Here we report an improved method for amplification of entire human papillomavirus (HPV) genomes. Using rTth DNA polymerase, XL (Perkin-Elmer, Foster City CA), and the accompanying XL PCR buffer system, we have successfully amplified 8-kb genomes from approximately 10 copies of input reference strain HPV16 DNA. This long PCR (LPCR) method was subsequently used to amplify the entire HPV16 genome from clinical specimens. The fidelity with which the rTth DNA polymerase XL amplified target sequences under our chosen amplification conditions was estimated by partial sequencing of cloned LPCR products generated from cloned reference strain HPV16 genomes. A region spanning the HPV16 E6, E7, and part of the E1 open reading frames (ORFs) was sequenced in 29 clones. A total of 33 nucleotide substitutions were observed in the 23.5 kb sequenced. This corresponds to an error frequency of approximately one error per 700 bases. Finally, LPCR methods were used to amplify entire, novel HPV genomes from clinical specimens. LPCR primer pairs were designed for amplification of seven potentially novel HPV types. Amplicons of approximately 8 kb were generated from five of the seven HPV types targeted. One of the LPCR-generated novel genomes, CP141, was subsequently cloned and a partial sequence was determined.

Amino Acid Sequence↗
PubMed1995

Human papillomavirus (HPV) type distribution and serological response to HPV type 6 virus-like particles in patients with genital warts.

Thirty-nine patients with condylomas (12 women and 27 men) attending a dermatology clinic were tested for genital human papillomavirus (HPV) DNA and for seroprevalence to HPV type 6 (HPV6) L1 virus-like particles. The L1 consensus PCR system (with primers MY09 and MY11) was used to determine the presence and types of HPV in sample specimens. All 37 (100%) patients with sufficient DNA specimens were positive for HPV DNA, and 35 (94%) had HPV6 DNA detected at the wart site. Three patients (8%) had HPV11 detected at the wart site, and one patient had both HPV6 and -11 detected at the wart site. Thirteen additional HPV types were detected among the patients; the most frequent were HPV54 (8%) and HPV58 (8%). Baculovirus-expressed HPV6 L1 virus-like particles were used in enzyme-linked immunosorbent assays to determine seroprevalence among the patients with warts. Seronegativity was defined by a control group of 21 women who were consistently PCR negative for HPV DNA. Seroprevalence was also determined for reference groups that included cytologically normal women who had detectable DNA from either HPV6 or HPV16 and women with HPV16-associated cervical intraepithelial neoplasia. Among the asymptomatic women with HPV6, only 2 of 9 (22%) were seropositive, compared with 12 of 12 (100%) female patients with warts. A similar trend in increased HPV6 seropositivity with increased grade of disease was found with the HPV16 DNA-positive women, whose seroprevalence increased from 1 in 11 (9%) in cytologically normal women to 6 in 15 (40%) among women with cervical intraepithelial neoplasia 1 or 3. However, only 4 of 25 (16%) male patients were seropositive. No factors examined, such as age, sexual behavior, or a history of warts, were found to definitively account for the gender difference in seroresponse.

Antibodies, Viral↗
PubMed1995

Human papillomavirus type 16 variant lineages in United States populations characterized by nucleotide sequence analysis of the E6, L2, and L1 coding segments.

Human papillomavirus type 16 (HPV16) nucleotide sequence variations in the E6 (nucleotide positions [nt] 104 to 559), L2 (nt 4272 to 5657), and L1 (nt 5665 to 7148) open reading frames (ORFs), and the long control region (nt 7479 to 7842), were examined in 29 selected United States isolates. Of 3,690 nucleotide positions, 129 (3.5%) varied. The maximum pairwise distance was 66 nucleotide differences, or 1.8%. Nucleotide variations within different genome segments were phylogenetically compatible, and nucleotide changes within E6, L2, and L1 contained phylogenetic information beyond that provided in the long control region. Most isolates were classified as members of HPV16 lineages that have been described previously. However, two novel phylogenetic branches were identified. The L2 ORF was the most variable coding segment. L2 synonymous and nonsynonymous nucleotide changes were distributed asymmetrically. The amino-terminal half of the L2 protein was remarkably conserved among all isolates, suggesting that the region is under evolutionary constraint. The amino-terminal region of the E6 ORF was relatively varied, especially at E6 amino acid positions 10 and 14. Several amino acid difference in the L1 ORF were observed between lineages. Forty-nine amino acid variations across all sequenced coding regions were observed. These amino acid differences may be relevant to differences in the generation of humoral or cell-mediated immune responses to HPV16 variants. Our data form a basis for considering HPV16 sequence variation in the rational design of vaccine strategies and as an epidemiologic correlate of cervical cancer risk.

Amino Acid Sequence↗
PubMed1994

Sexually transmitted diseases and other risk factors for cervical dysplasia among southwestern Hispanic and non-Hispanic white women.

OBJECTIVE: To assess risk factors for high-grade cervical dysplasia among southwestern Hispanic and non-Hispanic white women. DESIGN: Clinic-based case-control study. SETTING: University-affiliated gynecology clinics. SUBJECTS: Cases were Hispanic and non-Hispanic white women with biopsy-proven high-grade cervical dysplasia (n = 201). Controls were Hispanic and non-Hispanic white women from the same clinics with normal cervical epithelium (n = 337). METHODS: Study design included interviews focused on histories of sexually transmitted diseases, sexual behavior, reproductive histories, hygienic practices, contraceptive use, cigarette smoking, and diet. Laboratory studies included bacterial and protozoal cultures of the cervix; hybridization tests to identify human papillomavirus (HPV) genome with commercial (ViraPap and ViraType) and polymerase chain reaction-based assays; and serum antibody tests for herpes simplex virus, Chlamydia trachomatis, syphilis, hepatitis B, and hepatitis C. RESULTS: For both ethnic groups combined, after adjustment for ethnicity, age, and sexual behavior, the strongest risks for cervical dysplasia were associated with cervical HPV infection as identified by ViraPap (odds ratio [OR], 12.8; 95% confidence interval [CI], 8.2 to 20.0) or with polymerase chain reaction (OR, 20.8; 95% CI, 10.8 to 40.2). Other factors associated with dysplasia included cigarette smoking at the time of diagnosis (OR, 1.8; 95% CI, 1.2 to 2.8); low income (OR, 2.2; 95% CI, 1.2 to 4.0); low educational level (OR, 6.2; 95% CI, 3.4 to 11.1); history of any sexually transmitted disease (OR, 1.9; 95% CI, 1.3 to 2.7); and seroprevalence of antibodies to hepatitis B (OR, 1.8; 95% CI, 0.9 to 3.5). For Hispanic women, HPV 16/18 identified by ViraType was strongly associated with cervical dysplasia (OR, 171.0; 95% CI, 22.8 to 1280.5). Antibodies to herpes simplex virus type 2 were not associated with dysplasia in Hispanic women but were significantly associated with dysplasia among non-Hispanic whites. Risks associated with cigarette smoking also varied by ethnic group. CONCLUSIONS: The strongest risk factor associated with high-grade cervical dysplasia among clinic attendees was HPV infection. Although most of the risk factors we examined showed similar associations for dysplasia for both ethnic groups, our data suggest that several different risk factors may be relevant to the development of cervical dysplasia in Hispanics compared with non-Hispanic whites who attend the same clinics.

Adolescent↗
PubMed1994

A virus-like particle enzyme-linked immunosorbent assay detects serum antibodies in a majority of women infected with human papillomavirus type 16.

BACKGROUND: Previous studies have demonstrated that genital infection with high-risk types of human papillomavirus (HPV), most often HPV16, is the most significant risk factor for the development of cervical cancer. However, serologic assays that have been developed to identify high-risk HPV infection have either failed to associate serum reactivity with other indicators of HPV infection or have identified only a minority of HPV-infected individuals. PURPOSE: Our purpose was to determine whether a specifically developed enzyme-linked immunosorbent assay (ELISA) could detect IgG anti-HPV16 virion antibodies in the sera of women who had tested positive for genital HPV16 infection by DNA-based methods. METHODS: An ELISA was developed using newly developed HPV16 virus-like particles as antigens to detect anti-HPV16 virion IgG antibodies. These particles are comprised of HPV16 structural proteins that are self-assembled in insect cells after expression by recombinant baculoviruses. The sera of 122 women, whose HPV status had been previously evaluated by nucleic acid-based methods, were tested by this ELISA. RESULTS: The sera of 59% of women (32 of 54) positive for genital HPV16 DNA by polymerase chain reaction (PCR) were positive in the ELISA assay compared with sera from women who had tested negative for HPV DNA (P < .0005). In contrast, 6% of HPV DNA-negative women (two of 31) and 9% of women positive for low-risk HPV6/11 DNA (one of 11) were ELISA positive by this criterion. The sera of women who were DNA positive for two additional high-risk HPV types were evaluated; the sera of 31% of HPV18-positive (four of 13) and 38% of HPV31-positive women (five of 13) were positive in the HPV16 particle ELISA. The sera of 75% of HPV16 DNA-positive women with severe dysplasias (12 of 16) gave positive ELISA results. The sera of 67% of women (28 of 42) who tested positive for HPV16 DNA by both PCR and the less sensitive ViraType assay tested positive in the ELISA compared with 33% of women (four of 12) who were positive by PCR but negative by ViraType (P < .05). CONCLUSION: The majority of women with cervical HPV16 infection generate an IgG antibody response to conformationally dependent epitopes of HPV16 L1 that can be detected by ELISA. IMPLICATION: This particular ELISA, or a similar one incorporating virus-like particles of additional HPV types, may be useful in determining the natural history of high-risk HPV infection and perhaps help to identify women at risk for developing cervical cancer.

Adolescent↗
PubMed1994

HLA DR-DQ associations with cervical carcinoma show papillomavirus-type specificity.

Cervical carcinoma is now known to be associated with human papillomaviruses (HPV), but the evidence for a link with specific HLA loci is controversial. The role of genetic variation at the HLA class II loci and among HPV types in cervical carcinoma was investigated by PCR DNA amplification and oligonucleotide probe typing of paraffin-embedded invasive cervical cancer tissue from Hispanic patients and of cervical swabs from Hispanic controls. Certain HLA class II haplotypes (such as DRB1*1501-DQB1*0602) were associated significantly, while DR13 haplotypes were negatively associated with cervical carcinoma. These associations are HPV16-type specific. These results suggest that specific HLA class II haplotypes may influence the immune response to specific HPV-encoded epitopes and affect the risk of cervical neoplasia.

Adenocarcinoma↗
PubMed1994

Contraceptive and reproductive risks for cervical dysplasia in southwestern Hispanic and non-Hispanic white women.

BACKGROUND: Various contraceptive practices and reproductive factors have been associated with cervical neoplasia in case-control studies worldwide. METHODS: To investigate contraceptive and reproductive risk factors associated with high-grade cervical dysplasia in southwestern Hispanic and non-Hispanic white women, we carried out a clinic-based case-control study among university-affiliated clinic attendees. RESULTS: Oral contraceptive use ever (odds ratio [OR] = 0.4, 95% confidence interval [CI]: 0.2-0.9) and past diaphragm use (OR = 0.3, 95% CI: 0.1-0.8) were protective for dysplasia in analyses adjusted for age, ethnicity, sexual behaviour, and for cervical papillomavirus (HPV) infection. After further adjustment for Pap smear screening interval, oral contraceptive use ever remained protective for dysplasia. Vaginal deliveries were strongly associated with dysplasia with > 2 vaginal deliveries associated with a 3.9-fold increase in risk after adjustment for age, ethnicity, sexual behaviour, and HPV infection. Using logistic regression models to simultaneously control for effects of multiple factors as potentially related to cervical dysplasia, we found low educational attainment, cervical HPV infection, cigarette smoking, history of any sexually transmitted disease, and having one or more vaginal deliveries to be associated with dysplasia; oral contraceptive use and past diaphragm use also remained protective for high-grade cervical dysplasia in these regression analyses. CONCLUSIONS: The data suggest that use of oral contraceptives (ever) and past diaphragm use are protective for high-grade cervical dysplasia among Hispanic and non-Hispanic white women in New Mexico. The clinic-based perspective of this research (versus population-based studies) may help explain some of these findings.

Case-Control Studies↗
PubMed1994

Identification and assessment of known and novel human papillomaviruses by polymerase chain reaction amplification, restriction fragment length polymorphisms, nucleotide sequence, and phylogenetic algorithms.

The identification and taxonomy of papillomaviruses has become increasingly complex, as approximately 70 human papillomavirus (HPV) types have been described and novel HPV genomes continue to be identified. Methods and corresponding DNA sequence data bases were designed for the reliable identification of mucosal HPV genomes from clinical specimens. HPVs are identified by the amplification of a fragment of the L1 region by consensus primer polymerase chain reaction (PCR) and subsequent hybridization or restriction fragment length polymorphism analysis. L1 PCR fragments may be further characterized by nucleotide sequencing. Conservation of 30 (of 151) predicted amino acids identifies HPV genomic fragments, and nucleotide sequence alignments allow calculation of their phylogenetic relatedness. Sequence differences > 10% from any known HPV type suggest a novel HPV type. Phylogenetic relationships with known HPV types may permit predictions of biology. With these criteria, 10 PCR fragments were identified that would qualify as new genital HPV types after complete genomic isolation.

Amino Acid Sequence↗
PubMed1994

Identification of five novel human papillomavirus sequences in the New Mexico triethnic population.

Cervical specimens obtained from previous clinical studies at the University of New Mexico were screened for reference strain human papillomaviruses (HPVs) via HPV L1 consensus polymerase chain reaction (PCR) and type-specific oligonucleotide probe hybridization. PCR products that bound to an HPV generic probe but did not hybridize with HPV type-specific oligonucleotide probes were subjected to restriction endonuclease digestion analyses. Resulting restriction fragment length polymorphisms served as the basis for initial grouping of unknown HPVs and identification of potential reference strain HPV variants. MY09/MY11 PCR products containing putative novel HPV L1 fragments were cloned and sequenced. Five novel HPV sequences were identified in this study.

Base Sequence↗
PubMed1994

Epidemiology and partial nucleotide sequence of four novel genital human papillomaviruses.

Polymerase chain reaction (PCR)-based genital human papillomavirus (HPV) detection methods that use consensus primers have enabled the broad-spectrum detection of most characterized HPV types. In addition, these techniques have allowed the identification of potentially novel viral sequences in clinical specimens. These methods were used to determine the partial L1 nucleotide sequence (the region generated by L1 consensus primers MY09 and MY11) of four novel viruses. The prevalence of these viruses in cytologically normal and dysplastic cervical specimens and in invasive cervical cancer was also determined. The partial DNA sequences of W13B (MM4), PAP291 (MM7), PAP155 (MM8), and PAP238a (MM9) are most similar to HPV-51, -61, -61, and -34, respectively. Prevalence studies suggest that W13B and PAP238a are cancer-associated, while PAP155 and PAP291 appear to be lower-risk viruses.

Base Sequence↗
PubMed1994

Cigarette smoking and other risk factors for cervical dysplasia in southwestern Hispanic and non-Hispanic white women.

To assess smoking-related and other risk factors for high-grade cervical dysplasia in southwestern Hispanic and non-Hispanic white women in New Mexico, we conducted a clinic-based case-control study among attendees at university-affiliated gynecology clinics. We collected data on cigarette use, sexual behavior, past and current sexually transmitted diseases, hygienic practices, contraception, and diet. For both ethnic groups combined, after adjustment for the effects of human papillomavirus, sexual behavior, and other risk factors, cigarette smoking at the time of diagnosis was associated with high-grade dysplasia (odds ratio, 1.7; 95% confidence limits, 1.0-2.8). In contrast, former smoking was not associated with cervical dysplasia (odds ratio 0.9; 95% confidence limits, 0.5-1.5). Analyses showed dose-response relationships for the amount of cigarettes smoked per day and for cumulative exposure (pack-years of use) in association with cervical dysplasia. Although our study lacked the power to show statistically significant ethnic differences in smoking-related risks for dysplasia, smoking at the time of diagnosis, high pack-years of use, and smoking at the time of menarche were associated with dysplasia only for non-Hispanic white versus Hispanic women. Our data support hypotheses that implicate cigarette use as an etiological factor in the development of high-grade cervical dysplasia and suggest ethnic differences in risks for dysplasia among women attending the same clinics.

Adolescent↗
PubMed1993

Reactivity of neuroborreliosis patients (Lyme disease) to cardiolipin and gangliosides.

A subset of patients (50%) with neuroborreliosis (Lyme disease) showed IgG reactivity to cardiolipin in solid phase ELISA. In addition, a subset of patients with neuroborreliosis (29%) and syphilis (59%) had IgM reactivity to gangliosides with a Gal(beta 1-3) GalNac terminal sequence (GM1, GD1b, and asialo GM1). Anti-ganglioside IgM antibodies were significantly more frequent in these two groups of patients compared to patients with cutaneous and articular Lyme disease, primary antiphospholipid syndrome, systemic lupus erythematosus and normal controls. Correlative evidence and adsorption experiments indicated that antibodies to cardiolipin had separate specificities from those directed against the gangliosides. IgM antibodies to Gal(beta 1-3) GalNac gangliosides appeared to have similar specificities since these were positively correlated and inhibitable by cross adsorption assays. Given the clinical associations of patients with neuroborreliosis and syphilis with IgM reactivity to gangliosides sharing the Gal(beta 1-3) GalNac terminus, we suggest that these antibodies could represent a response to injury in neurological disease or a cross reactive event caused by spirochetes.

Adolescent↗
PubMed1993

Nonprotein antigens of Borrelia burgdorferi.

Preparative thin-layer chromatograms of chloroform-methanol extracts of Borrelia burgdorferi (B31) sonicates showed four fractions (Rf values of 0.84, 0.81, 0.66 and 0.61) that stained with iodine vapors, orcinol, or phospray, suggesting the presence of lipid-, carbohydrate-, and phosphorus-containing compounds. Sera from patients with Lyme disease showed IgM or IgG antibody reactivity to hydrophobic fractions, designated F1 and F2, in both early and late stages of the disease. Lack of constitutive amino acids in these fractions was shown by protein, amino acid, and peptide detection analyses. Sera from patients with syphilis, systemic lupus erythematosus, and antiphospholipid syndrome reacted to one or both of the fractions. Adsorption of sera from Lyme disease patients with intact B. burgdorferi resulted in significantly different pre- and postadsorption patterns of reactivity by whole cell ELISA, whereas adsorption with F1 and F2 resulted in similar pre- and postadsorption patterns. These fractions may not be present in aqueous whole cell or whole cell lysate ELISA antigens or in immunoblots.

Antigens, Bacterial↗
PubMed1992

Borrelia burgdorferi and other related spirochetes bind to galactocerebroside.

Spirochetes are agents of neurologic disease that may utilize specific neural cell surface molecules for adhesion. Borrelia burgdorferi, the etiologic agent of Lyme disease, bound to galactocerebroside (GalCer) in numbers that were two- to threefold greater than to ceramide and glucocerebroside, and four- to fivefold greater than to sphingosine, psychosine, sulfatide, cholesterol, and three membrane phospholipids. The adherence was greater to GalCer and ceramide with a higher content of alpha-hydroxyl fatty acids. Treponema phagedenis Reiter and Borrelia hermsii also bound to GalCer. The binding of B burgdorferi to GalCer was inhibited in a concentration-dependent manner by rabbit polyclonal and murine monoclonal antibodies to this glycosphingolipid component of myelin. The monoclonal antibody to GalCer also inhibited adhesion of the organisms to Schwann cells. Neither free D or L monosaccharides nor the lectin peanut agglutinin inhibited binding. Since B burgdorferi and other spirochetes cause neurologic disease, these results suggest a role for GalCer as a binding site in both the central and peripheral nervous systems.

Animals↗