Biomedical subjects

J K Kulski

Publications and source records attributed to J K Kulski.

At least 55 records · Page 3Linked to original sources

PubMed1996

Preparation of mycobacterial DNA from blood culture fluids by simple alkali wash and heat lysis method for PCR detection.

A sodium iodide-isopropanol (NI) method was compared with an alkali wash and heat lysis (AH) procedure for the preparation and extraction of DNA from BACTEC 13A blood culture fluid samples from AIDS patients for use in a PCR for the detection and identification of mycobacteria. The sensitivity and efficiency of the DNA extraction methods were assessed by a multiplex PCR which detected the members of the genus Mycobacterium and differentiated between M. intracellulare, M. tuberculosis, and M. avium isolates with a limit of detection of between 0.28 pg (67 cells) and 120 pg (28,571 cells) of standard mycobacterial DNA. The PCR amplified mycobacterial DNA prepared by the AH procedure from 40 acid-fast bacillus-positive blood cultures with growth index values of > 20 U but not from 48 blood cultures with growth index values of < 21 U. The AH method was about 10 times more sensitive than the NI method for extracting DNA from 13 acid-fast bacillus-positive BACTEC fluid samples for PCR analysis. The study shows that the AH procedure in combination with the multiplex PCR is a simple, specific, and sensitive method which can be used in the routine diagnostic laboratory to detect and identify different members of the genus Mycobacterium in blood culture fluid samples from AIDS patients.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Expression of the major capsid protein of human papillomavirus type 16 in Escherichia coli.

Major capsid proteins (MCPs) of various papillomaviruses have recently been expressed in heterologous cells as soluble and functional polypeptides. The host cells for producing these proteins have so far been of eukaryotic origin; however, E. coli has potential utility a host, with advantages over eukaryotic cells such as relatively simple culture requirements and greater ease of mutation of expressed sequences. We studied the expression by E. coli of the MCP of human papillomavirus type 16 (HPV16) using the gene derived from the 'prototype' HPV16 genome. Using expression vector pTrc99A, the protein was produced in full-length unfused form at levels of 3-4% of cell protein. Soluble polypeptide was detected, albeit at low levels. The level of solubility was not increased by growing cells at low temperature and slowing the rate of protein synthesis. The soluble protein was degraded at its carboxy terminus by an outer membrane protease of E. coli, OmpT, giving rise to two slightly shortened protein species of 52K and 56K in addition to the full-length 57K polypeptide. Since the MCP of prototype HPV16 is known to be prone to excessive aggregation compared with other papillomaviral MCPs, the recovery of soluble polypeptide indicates that E. coli is worth consideration as an alternative host to eukaryotes for producing these proteins.

Amino Acid Sequence↗

PubMed1995

Use of a multiplex PCR to detect and identify Mycobacterium avium and M. intracellulare in blood culture fluids of AIDS patients.

The presence of mycobacteria in blood culture fluids (BACTEC) of AIDS patients with positive growth indices (GIs, > 20 U) was investigated by using a multiplex PCR to detect and identify members of the genus Mycobacterium, M. avium, M. intracellulare, and M. tuberculosis. Three different methods of extracting mycobacterial DNA from blood culture fluid were compared for use with the multiplex PCR. Mycobacterial cells were pelleted from a small aliquot of blood culture fluid by centrifugation, and the DNA was extracted from cells by heat lysis or a sodium iodide-isopropanol or a phenol-chloroform method. DNAs of different sizes were amplified from a region of the MPB70 gene of M. tuberculosis (372 bp) and from a region of the 16S rRNA gene of members of the genus Mycobacterium (1,030 bp), M. intracellulare (850 bp), or M. avium (180 bp) as a multiplex PCR in a single tube. The amplified DNA products were detected by agarose gel electrophoresis and ethidium bromide staining in all 41 (100%) positive cultures after sodium iodide-isopropanol extraction, in 18 (44%) after heat lysis, and in 5 (12%) after phenol-chloroform extraction. Of the 41 positive cultures, 38 were identified as M. avium and 2 were identified as M. intracellulare by both routine methods and multiplex PCR. The remaining mycobacterium was identified as M. intracellulare by routine methods and as M. avium by the multiplex PCR. Another six blood cultures that were negative for the presence of acid-fast bacilli after Ziehl-Neelson staining were also negative by PCR. The study shows that the multiplex PCR is a useful method for the detection and identification of either M. avium or M. intracellulare in small samples of cultured BACTEC 13A fluid with positive GIs ranging from 21 to 999 U. The average time to positive GI was 18 days (median, 13 days) and ranged between 8 and 42 days. The multiplex PCR may permit cultured mycobacteria to be identified at an earlier stage than the routine methods which have been adapted for use with the BACTEC system. The results also show that the method selected for extracting mycobacterial DNA from blood culture fluids is crucial for providing sensitive and accurate PCR results.

AIDS-Related Opportunistic Infections↗

PubMed1994

Quantitation of human cytomegalovirus DNA in leukocytes by end-point titration and duplex polymerase chain reaction.

The presence of human cytomegalovirus (CMV) DNA and cellular DNA in leukocytes was detected by duplex polymerase chain reaction (PCR) and quantitated by end-point titration. Two different duplex PCR methods were used to co-amplify CMV DNA and a 536 bp fragment of globin DNA. MIE-globin PCR amplified a 435 bp fragment of the major immediate early (MIE) gene of CMV DNA whereas the LA-globin PCR amplified a 200 bp fragment of the late antigen (LA) gene of CMV DNA. PCR products were separated by electrophoresis in 3% agarose gels and detected by ethidium bromide staining. Amplification of globin DNA was included in the PCR as a positive control to monitor the accuracy and reproducibility of the PCR assay and to provide a reference point for CMV DNA levels. End-point titration PCR using known amounts of recombinant CMV DNA and human placental DNA showed that the end-point titres of the amplified CMV DNA correlated directly with the amount of CMV DNA in the sample. The limit of detection of MIE-globin and LA-globin PCR was 1 ng for placental DNA, and 10 fg (1000 copies) for CMV-MIE DNA and 1 fg (100 copies) for CMV-LA DNA, respectively. The amount of CMV DNA was quantitated in leukocytic lysates of 16 immunocompromised patients, who were tested for the presence of CMV in blood by cell culture, and of four normal controls. The blood concentration of CMV DNA, calculated as the number of copies of CMV DNA per microgram of leukocyte DNA, varied between 10(4) and 10(7) in the seven bloods that were CMV-cell-culture-positive, and between 10(2) and 10(4) in the blood of five patients that were CMV-cell-culture-negative. CMV DNA was undetected by PCR in the blood of another eight CMV-negative cases. This study shows that end-point titration and duplex PCR can be used as a simple and rapid method to quantitate CMV DNA in blood of patients that are either CMV-positive or CMV-negative by cell culture. Quantitation of CMV DNA in blood by end-point titration PCR has potential to differentiate between asymptomatic CMV infection and symptomatic CMV disease, and to monitor viral load during viral therapy.

AIDS-Related Opportunistic Infections↗

PubMed1993

Detection of cytomegalovirus in blood donors by the polymerase chain reaction.

A polymerase chain reaction (PCR) assay was developed and optimized to detect cytomegalovirus (CMV) DNA in the blood of 86 normal donors who had originally tested seropositive for CMV. Evidence of previous or current infection with CMV was determined by rescreening of the blood for CMV antibodies and by detecting the presence of infectious virus in the white cells by cell culture. DNA was extracted from the blood of donors by a manual or an automated method and amplified by PCR using primers from the major immediate early gene of CMV DNA. The amplified product was detected by visualization of a fluorescent 435-base pair DNA band in an electrophoretic agarose gel after ethidium bromide staining and confirmed by slot-blot DNA hybridization using an oligonucleotide probe with complementarity for the major immediate early gene. Seven (8%) of the 86 donors were positive for CMV DNA in both fluorescence and hybridization studies. These donors were also antibody positive. While 74 (86%) of the 86 donors were positive for the presence of CMV antibodies in enzyme-linked immunosorbent assay, none was positive for virus in cell culture. PCR has the potential to be an effective and reliable procedure for the detection of CMV DNA in donor blood, but further study is required for this technique to be used for diagnostic or routine screening purposes.

Adult↗

PubMed1992

Detection of papillomaviral-like DNA sequences in premalignant and malignant perineal lesions of sheep.

Small hyperkeratotic and ulcerated lesions and clinical cancers were isolated from the perineal region of sheep and examined for evidence of papillomavirus infection by various criteria including gross morphology, histology, immunohistochemistry and DNA hybridisation. No specific diagnostic features of papillomaviral infection by immunohistochemistry were found, although some lesions showed gross morphological and histological features similar to papillomaviral effect in other species. DNA hybridisation analysis, using human papillomaviral type 11, 13, 16 and 18 DNA probes under conditions of reduced stringency (Tm-40 degrees C), detected homologous sequences in two thirds of the biopsies examined. These homologous sequences occurred in benign hyperkeratosis as well as invasive squamous cell carcinomas but were much more frequently isolated from carcinomas. This finding suggests that a papillomavirus is associated with the development of squamous cell carcinomas of the perineum of sheep.

Animals↗

PubMed1990

Detection of human papillomavirus in reprocessed routine Papanicolaou smears by DNA hybridization.

DNA dot blot hybridization was used for the detection of human papillomavirus (HPV) types 6, 11, 16, and 18 in reprocessed routinely collected Papanicolaou smears. DNA was extracted from the smears with alkaline lysis and applied onto a nitrocellulose filter. The specificity and sensitivity of the dot blot hybridization on reprocessed Papanicolaou smears were confirmed by Southern blot analysis of selected samples, using CaSki, SiHa cell lines as positive controls and HF 32 as negative controls. From 42 normal smears and 44 abnormal smears with koilocytosis present, 9 (21%) and 43 (98%), respectively, were positive for HPV 6/11/16 or 18. These results show that reprocessed Papanicolaou smears in combination with DNA hybridization have potential application in retrospective studies on the prevalence and distribution of HPV infection.

Blotting, Southern↗

PubMed1990

Survey of histologic specimens of human cancer for human papillomavirus types 6/11/16/18 by filter in situ hybridization.

Histologic specimens (317) of genital and nongenital cancers and normal tissue were analyzed for the presence of the DNA of human papillomavirus (HPV) 6, 11, 16, and 18 by filter in situ hybridization performed on paraffin-embedded, formalin-fixed tissue (HISTOFISH). HPV DNA was found in 73 of 172 (42%) anogenital lesions and 17 of 116 (15%) nonanogenital carcinomas. No HPV DNA was found in normal mouse skin (five samples), human autopsy liver (two samples), or kidney (eight samples), or in carcinomas of the breast (three samples), bladder (five samples), or colon (nine samples). Of the nongenital tumors, HPV DNA was found in the carcinomas of the lung (2 of 5), anus (7 of 18), esophagus (9 of 39), buccal cavity (1 of 5), and larynx (5 of 50). HPV DNA was also detected in 2 of 11 histologically normal specimens of the cervix and 1 of 3 human skin lesions. The detection of HPV DNA in carcinomas of the lung, larynx, and esophagus as well as in the anogenital region confirms recent suggestions that HPV types 6, 11, 16, and 18 have a wider association with different types of cancer than previously believed. The study also shows that HISTOFISH is a useful method for detecting HPV-DNA in histologic specimens.

Anus Neoplasms↗

PubMed1989

Human papillomavirus coinfections of the vulva and uterine cervix.

DNA filter in situ hybridisation (FISH) was used to determine the presence of human papillomavirus (HPV) genotypes 6/11, 16/18, and 31/33 in cell scrapes of the cervix and vulva of 128 women who had precancerous lesions and/or HPV infection of the cervix diagnosed by cytology, colposcopy, and histology. HPV-DNA was found in 87 (68%) vulval and 95 (74%) cervical cell scrapes, and in both the vulval and cervical scrapes of 73 (57%) women, but not in either the vulva or the cervix of 19 women (15%). Of the HPV-DNA-positive smears, the prevalence of the HPV types was 61% HPV 16/18, 14% HPV 6/11, 3% HPV 31/33, and 22% HPV 6/11 and 16/18. By contrast, HPV-DNA was not detected in the cervical smears of a control group of 35 women who were assessed to be free of cervical abnormalities by colposcopy and cytology. The epithelial response of the vulva and the cervix to application of 5% acetic acid was assessed by colposcopy and the results correlated with the presence of HPV genotypes. A possible or definite disorder of the cervix and vulva was detected by colposcopy in 95 (74%) and 96 (75%) of the 128 cases, respectively. The colposcopic assessment of the vulva was inconclusive in ten cases (8%), and only eight women (6%) were found to be free of both a vulval and cervical disorder. This study shows subclinical papillomavirus infections of the vulva frequently coexist with HPV infections and precancerous lesions of the cervix.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Detection of human papillomavirus type 16 DNA in cervical swabs and formalin-fixed, paraffin-embedded squamous cell carcinomas of non-genital tissues using a synthetic oligodeoxynucleotide probe.

The potential of using a chemically synthesized oligodeoxynucleotide as a diagnostic probe to detect human papillomavirus type 16 (HPV-16) in genital infections was evaluated by comparing it with a cloned full-length HPV-16 probe in dot-blot DNA hybridizations. An oligonucleotide sequence, 20 bases in length from the E6 region of HPV-16 (E6 oligo) and different from the DNA sequences of HPV types 6, 11 and 18 by at least 2 base pairs, was chosen for chemical synthesis. The oligoprobe, which was 5'-end labelled with [32P]dATP, was found to be specific, but approximately ten times less sensitive than the full-length radiolabelled probe of HPV-16, in dot-blot hybridizations with the DNA of HPV-6, -11, -16 and -18, HPV positive and negative cell-lines. From 36 cervical or vulval scrapes two samples were found positive with both cloned HPV-16 and oligoprobe hybridization. Of 21 samples of formalin-fixed, paraffin-embedded squamous cell carcinomas originating from anus, oesophagus, penis, colon, breast and skin only 4 anal squamous cell carcinomas were positives when hybridized with cloned HPV-16 DNA or with the oligoprobe. This study confirms that HPV-16, which is frequently associated with squamous cell carcinoma of the cervix is also strongly associated with squamous cell carcinoma of the anus.

Autoradiography↗

PubMed1989

Enhancement of u.v.-induced skin carcinogenesis in the hairless mouse by inoculation with cell-free extracts of skin tumours.

The presence of papillomaviral-like DNA has been described in ultraviolet light-induced tumours in the skin of the hairless mouse (14). Here we describe the effects of the inoculation of cell-free extracts of ultraviolet light-induced tumours into the scarified skin of normal hairless mice, prior to exposure of the mice to a cumulative carcinogenic dose of ultraviolet light. Extracts from papillomas or squamous cell carcinomas enhanced the susceptibility of the inoculated mice to ultraviolet light-induced tumorigenesis, if the extracts contained papillomaviral DNA sequences detected by cross-hybridization with Mastomys natalensis papillomaviral DNA. The recipient mice developed a greater tumour incidence, tumour yield, tumour diameter and degree of malignancy.

Animals↗

PubMed1989

Identification of papillomaviral DNA sequences in hairless mouse tumours induced by ultraviolet irradiation.

Papillomas, carcinomas in situ and squamous cell carcinomas were induced using ultraviolet irradiation in the hairless mouse strain Mus musculus HRA/Skh. DNA extracted from biopsies was examined using Mastomys natalensis papillomaviral DNA as a hybridization probe at reduced stringency. Sequences homologous to the probe were detected in 16 of 24 papillomas, five of five carcinomas in situ and six of 38 squamous cell carcinomas. A number of tumour DNAs (16/33) also hybridized with mixed DNAs of human papillomavirus types 11, 13, 16 and 18 at reduced stringency. This suggests a role for the hairless mouse as a laboratory model for the study of the involvement of papillomaviruses in malignant transformations.

Animals↗

PubMed1988

Detection of human papillomavirus DNA in cell scrapes and formalin-fixed, paraffin-embedded tissue of the uterine cervix by filter in situ hybridisation.

Filter in situ hybridisation (FISH) was used to detect the presence of DNA of human papillomavirus (HPV) types 6/11 or 16/18 in cell scrapes (CYTOFISH) and formalin-fixed, paraffin-embedded biopsies (HISTOFISH) taken from the uterine cervices of 19 women. Paraffin tissue sections collected for HISTOFISH were either digested with pepsin or lysed with alkali/Triton X-100. The digest or lysate of the tissue sections and cell scrapes were applied to nylon or nitrocellulose membranes for nucleic acid hybridisation using 32P-labeled HPV-DNA probes. CYTOFISH and HISTOFISH were compared directly by taking samples for each method from the cervices of the same women. Of 19 women examined by colposcopy, cytology, and histology, eight were assessed as normal and 11 had evidence of a cervical disorder and/or the presence of HPV infection. Whereas no HPV-DNA was detected in the normal cases, the presence of HPV-DNAs was detected by both CYTOFISH and HISTOFISH in 11 cases with histological evidence of HPV infection and/or dysplasia. In these HPV positive cases, eight contained HPV 16/18, two HPV 6/11, and one a mixed infection of HPV 6/11/16/18. The high correlation between the results of CYTOFISH and HISTOFISH shows that formalin-fixed, paraffin-embedded cervical biopsies are suitable specimens for the detection and typing of HPV-DNA by FISH. Both CYTOFISH and HISTOFISH should facilitate studies on the prevalence and distribution of HPVs and their association with neoplasia.

Autoradiography↗

PubMed1988

Comparison of some biological effects of epidermal growth factor and commercial serum albumin on the induction of alpha-lactalbumin in rat and rabbit mammary explants.

Commercial preparations of serum albumin from six species can markedly enhance the prolactin-independent induction of alpha-lactalbumin in mammary explants from pregnant rats, and evoke such induction in the tissue from virgin rats. These effects are similar to those of epidermal growth factor (EGF) reported previously. The stimulatory activity of bovine serum albumin (BSA) resides in a putative impurity in the albumin. Charcoal extraction and gel filtration of the BSA results in complete loss of activity. Of the five milk protein mRNAs studied, only alpha-lactalbumin mRNA is induced by insulin, glucocorticoid and serum albumin in the absence of prolactin. Despite these similarities, the biological effects of serum albumin and EGF on mammary tissue diverge in some respects. They appear to operate by different mechanisms since their effects on the rat system are additive. Furthermore, while both inhibit prolactin-mediated induction of alpha-lactalbumin in rabbit mammary explants, cortisol converts EGF into a stimulatory agent, but merely blocks the inhibitory effect of serum albumin. The results emphasize that commercial serum albumin is not to be regarded simply as an inert protein additive to culture media.

Animals↗

PubMed1987

Detection of DNA of human papillomavirus types 6/11 and 16/18 in cell scrapings of the uterine cervix by filter in situ hybridisation. Correlation with cytology, colposcopy and histology.

The application of filter in situ hybridisation (FISH) to detect the presence of the DNA of human papillomavirus genotypes 6/11 and/or 16/18 in cell scrapings of the uterine cervix of 248 women in Western Australia is described. The results obtained by FISH are related to cervical dysplasia as assessed by cytology, colposcopy and histology. The detection of HPV infection was more sensitive and specific by FISH than by either histological/cytological evidence of an HPV cytopathic effect (koilocytosis) or immunohistochemical staining for HPV capsid antigen using antiserum against genus specific antigen of the bovine papillomavirus. Viral DNA was detected by FISH in 65% of women with atypical cytology and of the HPV positive cases, 68% were HPV 16/18, 22% HPV 6/11 and 10% of mixed types. HPV-DNA was detected in the cervical smears of 16 women who also had HPV capsid antigen (HPV-Ag) in their cervical biopsies; HPV 6/11 was found in 4 cases and HPV 16/18 in 12 cases. The relative frequency of the HPV-Ag positive cases decreased markedly from 44% to 4% with an increase in the severity of cervical dysplasia. By comparison, the percentage of HPV-DNA positive cases remained relatively constant between 70% and 80% for all 3 categories of dysplasia. Of these, the percentage of HPV 6/11 positives decreased slightly with an increase in the severity of dysplasia as assessed by either cytology or histology, whereas the percentage of HPV 16/18 positive cases was relatively constant. HPV-DNA was found in cervical smears of 11 of 48 (23%) women who were diagnosed colposcopically to have atypical transformation zone of the cervix. In 138 women with an atypical transformation zone, 96 (70%) were found to have HPV-DNA with HPV 16/18 contributing to 83% of the HPV positive cases. All four genotypes of HPV were found to be associated with the colposcopic morphology of mosaicism (26 cases) but only HPV 16/18 was found in 12 HPV-DNA positive cases associated colposcopically with punctation and an atypical transformation zone. The detection and typing of HPV-DNA in cell scrapings by FISH is a relatively fast and non-invasive procedure which complements cytology, colposcopy and histology and should be useful in further studies of the natural history of different HPV infections and their role in cervical cancer.

Adolescent↗

PubMed1987

DNA sequences of human papillomavirus types 11, 16 or 18 in invasive cervical carcinoma of Western Australian women.

The presence of human papillomavirus (HPV) types 11, 16 and 18 in 77 biopsies of cervical intraepithelial neoplasia (dysplasia) and carcinoma of the uterine cervix of a sample of women from Western Australia was examined using "Southern" blot hybridisation. HPV-DNA was found in 17 of the 23 dysplasias and 43 of the 54 invasive carcinomas examined but not in the 5 biopsies obtained from areas assessed as normal by colposcopy and histology. Five of 11 biopsies of mild to moderate dysplasias contained HPV type 11 (HPV-11), 2 HPV-16 and 1 HPV-18. Of 12 severe dysplasias/carcinoma in situ, 2 contained HPV-11, 4 HPV-16 and 2 HPV-18. One biopsy contained both HPV-11 and HPV-16. Of 45 squamous cell carcinomas examined for HPV-DNA, 24 contained HPV-16, 5 HPV-11 and 1 HPV-18. Both HPV-11 and HPV-16 were found in 6 of the squamous cell carcinomas and 2 contained both HPV-16 and HPV-18. Of 6 adenosquamous carcinomas examined, 3 contained HPV-DNA, 2 with HPV-16 and 1 with HPV-11. HPV types 16 or 18 were also found in 2 of 3 adenocarcinomas. This study shows a strong association between the papillomavirus and uterine cervical cancer in a sample of women from Western Australia. HPV-16 was more frequently associated with severe dysplasia and cancer than with mild or moderate dysplasia supporting the view that this HPV genotype may have a greater oncogenic potential than HPV-11.

Adenocarcinoma↗

PubMed1987

Assessment of precancerous lesions of the uterine cervix for evidence of human papillomavirus infection: a histological and immunohistochemical study.

Cervical biopsies obtained by colposcopic direction from 358 women were histologically examined for squamous dysplasia (cervical intra-epithelial neoplasia; CIN) and human papillomavirus (HPV) infection. Of the 358 biopsies, 136 were stained by an immunoperoxidase method using an antiserum against genus-specific (common) antigen of bovine papillomavirus. HPV antigens were detected in 40% of biopsies showing definite histological evidence of HPV effect, and in 7.9% and 2.6% of those with possible or no HPV effect, respectively. HPV effect was commonly seen in association with CIN. The frequency of histological evidence of HPV effect and positive immunoperoxidase staining decreased with increasing grades of CIN. HPV antigen was found in 57% of areas of HPV change with minor atypia, 34% of zones of CIN I and in only 8% of zones of CIN II. No antigenic staining or definite histological evidence of HPV effect was observed within areas of CIN III. Antigen was generally confined to the nuclei of superficial koilocytes, cells with lesser degrees of perinuclear clearing and parakeratotic cells. These results how a strong association between HPV infection and precancerous lesions of the uterine cervix and are consistent with the hypothesis that production of the HPV structural antigen requires a high degree of squamous cell maturation. The immunoperoxidase findings and the histopathological observations support the view that HPV change and dysplasia are part of a morphological continuum in which the cytopathic effect of HPV is expressed mainly in lower grades of dysplasia.

Adolescent↗

PubMed1986

Comparison of peroxidase-antiperoxidase and avidin-biotin complex methods for the detection of papillomavirus in histological sections of the cervix uteri.

A study was undertaken to determine the relative sensitivities of the peroxidase-antiperoxidase (PAP) and avidin-biotin complex (ABC) methods for the detection of human papillomavirus (HPV) antigens in acetic acid-ethanol fixed paraffin-embedded cervical tissue. Tissue sections prepared from 14 women suspected to have HPV infections with either atypia or dysplasia were stained immunohistochemically using an antiserum against genus-specific (common) antigen of bovine papillomavirus. Detection of HPV antigen was approximately twice as frequent by the ABC method as by the PAP method. Of the 14 cases studied, 43% were found to be HPV positive by the PAP method whereas 79% were HPV positive by the ABC method. In addition, the number of cells found to be HPV positive by the ABC method was approximately double the number by the PAP method.

Antigens, Viral↗