AgarCyto: a novel cell-processing method for multiple molecular diagnostic analyses of the uterine cervix.

In diagnostic cytology, it has been advocated that molecular techniques will improve cytopathological diagnosis and may predict clinical course. Ancillary molecular techniques, however, can be applied only if a sufficient number of preparations are made from a single cell sample. We have developed the AgarCyto cell block procedure for multiple molecular diagnostic analyses on a single scraping from the uterine cervix. The optimized protocol includes primary fixation and transport in ethanol/carbowax, secondary fixation in Unifix, and embedding in 2% agarose and then in paraffin according to a standard protocol for biopsies. More than 20 microscopic specimens were produced from a single AgarCyto cell block, and standard laboratory protocols have been successfully applied for H&E staining, immunohistochemistry for Ki-67 and p53, and in situ hybridization for the centromere of human chromosome 1 and human papilloma virus Type 16. In addition, single AgarCyto sections yielded sufficient input DNA for specific HPV detection and typing by LiPA-PCR, and the protocol includes an option for DNA image cytometry. The AgarCyto cell block protocol is an excellent tool for inventory studies of diagnostic and potentially prognostic molecular markers of cervical cancer.

Interphase cytogenetic analysis of cervical intraepithelial neoplasia.

The aim of this study was to detect numerical chromosomal aberrations that may be involved in the progression of cervical intraepithelial neoplasia (CIN) toward cervical carcinoma. Therefore, cervical lesions (five CIN 1, seven CIN 2, six CIN 3, six invasive carcinomas, and six normal samples) were studied by in situ hybridization (ISH) on serial 3-microm-thick paraffin tissue sections, using a panel of eight centromeric DNA probes for chromosomes 1, 3, 6, 7, 8, 11, 17, and X. An estimation of the percentage of dysplastic epithelium with abnormal ISH signals per nucleus was made. Chromosome aneusomy could be detected in all persisting and high-grade CIN lesions and invasive carcinomas. In most cases, when one of the chromosomes showed aneusomy then all studied chromosomes showed numerical changes. Interestingly, the abnormal ISH signals were found only in a varying part of the morphologically dysplastic epithelium, the remainder showing no such changes. In aneuploid regions of the CIN 1 lesions the mean chromosome index for all chromosomes was 1.97+/-0.03 with a range of 1.92 to 2.00. The chromosome index ratios of chromosomes 1, 7, and X showed a significant positive correlation with CIN grade (r > or = 0.74; P < or = 0.006). It is concluded that chromosome aneusomy of chromosomes 1, 7, and X may be involved in the progression of CIN lesions.

Human papilloma virus detection by in situ hybridisation signal amplification based on biotinylated tyramine deposition.

Aim-To describe a method for amplifying human papilloma virus (HPV) in situ hybridisation (ISH) signals.Methods-Three human cervical cell lines, namely CaSKi, HeLa and SiHa, containing different copy numbers of integrated HPV DNA were studied. Following ISH, catalysed reporter deposition (CARD), based on the deposition of biotinylated tyramine at the location of the DNA probe, was used to amplify the ISH signal.Results-Using CARD-ISH, one to three HPV type 16 copies were detected in situ both in cell suspensions and paraffin wax sections of SiHa cells. CARD-ISH can also be used to detect oncogenic HPV DNA sequences, such as HPV types 16 and 18, in routinely processed formalin fixed, paraffin wax embedded cervical specimens.Conclusions-CARD-ISH is a fast and highly sensitive ISH method for the routine detection of low copy number HPV DNA sequences in cervical cell lines and routinely processed tissue sections. Application of this technology also enables the routine detection and cellular localisation of other viral DNA sequences present at copy numbers below the detection limit of conventional ISH methods.

Persistent gestational trophoblastic disease: DNA image cytometry and interphase cytogenetics have limited predictive value.

DNA flow cytometry has shown a wider spectrum of DNA content in the complete hydatidiform mole (CM) than the originally reported diploidy. Conflicting results have been published about the relationship of DNA content and the occurrence of persistent gestational trophoblastic disease (PGTD). In the present study, 71 cases of CM and 4 cases of partial mole accompanied by PGTD and 100 cases of CM without PGTD were evaluated with DNA image cytometry for differences in DNA-ploidy pattern, expressed as the 2.5c and 5c exceeding rates. A pilot study of 20 cases of each group was performed using interphase cytogenetics to detect differences in the frequency of numerical chromosomal aberrations and in sex chromosome composition. For this purpose, DNA probes specific for the pericentromeric regions of chromosomes 1 and X and for the long arm of chromosome Y were incubated on 6-micron paraffin tissue sections. The results showed no differences between CMs with or without PGTD; DNA polyploidy occurred in 99% and 98% of cases, respectively; the 2.5c exceeding rate and 5c exceeding rate were 62.6 and 62.4, and 6.5 and 6.0, respectively. The frequency of numerical chromosomal aberrations as detected by interphase cytogenetics was 23.4 and 22.8%. An XY pattern was found in 3 of 20 cases of CM with PGTD and in 4 of 20 cases of CM without PGTD. The four cases of partial mole showed a DNA-ploidy pattern identical to that of a CM. For this reason, they would be better reclassified as CMs, despite the presence of nucleated red blood cells or amnion. Although nuclear atypia and corresponding increased DNA content is pronounced but variable in CMs, the occurrence of PGTD is not related to variations in quantitative DNA content nor to gross heterology or homology in sex chromosomes.

Complete hydatidiform mole in twin pregnancy: differentiation from partial mole with interphase cytogenetic and DNA cytometric analyses on paraffin embedded tissues.

Six cases of hydatidiform mole associated with normal chorionic villi and a normal embryo/fetus (in five cases) were investigated with interphase cytogenetic and DNA cytometric analyses for diagnostic purposes. DNA probes specific for the pericentromeric regions of chromosomes 1 and X and for the long arm of chromosome Y were used. In four cases a dizygotic twin pregnancy could be proven. In these cases, the histologically normal chorionic villi showed an XY DNA-diploid pattern, consistent with a normal male conceptus, and the molar chorionic villi a XX pattern. In the other two cases an identical sex chromosomal pattern was found in the normal and in the molar villi (XX/XX and XY/XY respectively). In all six cases the molar placental tissues showed prominent trophoblastic hyperplasia with DNA-polyploidy, consistent with a complete hydatidiform mole. In two cases persistent gestational trophoblastic disease developed. It is emphasized that twin pregnancies composed of a normal conceptus and a complete mole have a relatively high risk for the development of persistent trophoblastic disease and therefore, should be carefully differentiated from triploid partial moles with a relatively low risk of persistent gestational trophoblastic disease. These case reports indicate that additional interphase cytogenetic and DNA cytometric analyses are useful in this differential diagnosis.

Antiglomerular basement membrane nephritis in beige mice. Deficiency of leukocytic neutral proteinases prevents the induction of albuminuria in the heterologous phase.

Antiglomerular basement membrane (GBM) nephritis with massive albuminuria can be induced in mice by injection of heterologous antibodies against mouse GBM. The albuminuria and the glomerular lesions in this model are not mediated by complement, but are dependent on the presence of polymorphonuclear granulocytes (PMN) in the glomeruli. Neutral serine proteinases and reactive oxygen metabolites produced by activated PMN have been implicated as agents contributing to tissue damage. We examined the role of leukocytic neutral proteinases by comparing the glomerular damage and albuminuria after injection of rabbit anti-mouse GBM antibodies in normal control mice (C57BL/6J, +/+) and in beige mice (C57BL/6J,bg/bg) in which PMN are deficient of the neutral proteinases elastase and cathepsin G. The dose-dependent albuminuria that occurred in control mice after injection of 1.4-22 mg of anti-GBM antibodies was not observed in beige mice, despite a comparable influx of PMNs in the glomeruli. By electron microscopy both strains showed a similar attachment of PMN to the denuded GBM together with swelling and necrosis of endothelial cells. Elastase activity of extracts from PMN of beige mice was only 10-15% of the activity of control mice. In vitro, GBM degradation by PMN extracts of beige mice was 70% lower than that seen in control experiments. PMNs of beige and control mice showed no differences in superoxide production. In addition, administration of scavengers of reactive oxygen metabolites, such as catalase and desferrioxamine, did not prevent the albuminuria in this model. These findings support the important contribution of leukocytic neutral proteinases to the induction of albuminuria in the acute phase of anti-GBM nephritis in the mouse.

Antiglomerular basement membrane nephritis in the mouse. Study on the role of complement in the heterologous phase.

The role of complement was examined in a model of antiglomerular basement membrane nephritis in the mouse, induced by intravenous injection of goat anti-mouse glomerular basement membrane serum, and characterized by early glomerular lesions and a dose-dependent albuminuria. We compared the reaction after injection of the antiserum in complement-normal B10.D2 new mice with that in congenic, congenitally C5-deficient B10.D2 old mice, and in both strains after C3 depletion by treatment with cobra venom factor. The dose-dependent albuminuria was not affected by the absence of complement activation. Also, deficiency of C3 and/or C5 had no inhibitory effect on the histologic glomerular lesions: it did not reduce the influx of polymorphonuclear granulocytes in the glomerular capillary vessels, nor prevented the eventual intravascular coagulation. We conclude that complement-independent mechanisms are involved in the development of the heterologous phase of antiglomerular basement membrane nephritis in the mouse.