CD40 ligand-CD40 interaction induces chemokines in cervical carcinoma cells in synergism with IFN-gamma

Cellular immunity plays a major role in controlling human papilloma virus infection and development of cervical carcinoma. Mononuclear cell infiltration possibly due to the action of chemokines becomes prominent in the tumor tissue. In fact, the macrophage chemoattractant protein-1, MCP-1, was detected in cervical squamous cell carcinoma in situ, whereas absent in cultured cells. From this, unknown environmental factors were postulated regulating chemokine expression in vivo. In this study, we show high CD40 expression on cervical carcinoma cells and CD40 ligand (CD40L) staining on attracted T cells in tumor tissue, suggesting a paracrine stimulation mechanism via CD40L-CD40 interactions. We therefore investigated chemokine synthesis in nonmalignant and malignant human papilloma virus-positive cell lines after CD40L exposure. Constitutive expression of MCP-1, MCP-3, RANTES, and IFN-gamma-inducible protein-10 was almost undetectable in all cell lines tested. CD40L was able to induce MCP-1 production; however, despite much higher CD40 expression in malignant cells, MCP-1 induction was significantly lower compared with nontumorigenic cells. After sensitization with IFN-gamma, another T cell-derived cytokine showing minimal effects on CD40 expression levels, CD40 ligation led to a more than 20-fold MCP-1 induction in carcinoma cell lines. An even stronger effect was observed for IFN-gamma-inducible protein-10. Our study highlights the synergism of T cell-derived mediators such as CD40L and IFN-gamma for chemokine responses in cervical carcinoma cells, helping to understand the chemokine expression patterns observed in vivo.

Functional significance of sequence variation in the E2 gene and the long control region of human papillomavirus type 16

The long control region (LCR) and the E2 protein of human papillomaviruses (HPV) are the most important viral factors regulating transcription of the viral oncogenes E6 and E7. Sequence variation within these genomic regions may have an impact on the oncogenic potential of the virus. Sequence variation in the LCR and in the E2 gene of human papillomavirus type 16 (HPV-16) isolates originating from cervical cancer patients from East Hungary was studied. In 30 samples, sequencing and/or single-strand conformation polymorphism analysis revealed variants belonging to the European variant lineage of HPV-16. These variants differed from the reference European clone only slightly in their E2 and LCR sequences. Three samples represented variants belonging to the Asian-American group. These differed from the published reference sequence at several positions in the LCR and E2 regions. Compared to the reference clone, the LCR clones of the European isolates showed very similar transcriptional activities, while that of an Asian-American isolate had approximately 1.7-fold increased activity. Most of the increased activity of the Asian-American isolate could be ascribed to nucleotide changes found at the 3' end of the LCR (nt 7660-7890). The transcriptional transactivation potentials of the HPV-16 E2 isolates differed only slightly from each other, and the differences seemed to be independent of the taxonomic position of the isolates.

[Removal of YY1 binding sites in HPV 16 LCR increases viral transforming activities on mouse fibroblasts]

OBJECTIVE

To study the effect of removal of YY1 binding sites within the LCR region of HPV 16 on viral transforming activity.

METHODS

Previously we had generated new plasmids carrying HPV 16 whole genome, which contained naturally occurred mutated LCR sequences. The viral transforming abilities on mouse fibroblasts were evaluated in anchorage-independent assays, while the expression and activity of YY1 protein in fibroblasts were tested with EMSA and luciferase assays.

RESULTS

YY1 protein was expressed in mouse fibroblasts C127, with ability for DNA binding and repression on P97 activity. Both HPV 16 wild-type DNA and mutated DNAs were transfected into C127 cells and spread to the soft-agarose mediums after selecting with G 418. The growth numbers of the cells transfected with mutated HPV 16 DNAs were 2-10 fold more than that with wild-type HPV 16 DNA.

CONCLUSION

Like in epithelial cells or cell lines, transcription regulator YY1 is widely expressed in rodent fibroblasts. Removal of YY1 binding motifs can elevate in the context of the whole genome, the anchorage independent growth ability and the transforming capacity of HPV 16 on the mouse fibroblasts.

A bioassay for interferon type I based on inhibition of Sendai virus growth

The expression of type I interferons (IFNs) in eukaryotic cells represents a first line of defense against viral infection. Cells pretreated by IFNs do not support viral replication and are protected from virus-induced cell destruction. A challenge of IFN-pretreated cells with vesicular stomatitis virus (VSV) is frequently used to quantitate this cytokine because, on the one hand, the replication of VSV is highly sensitive to IFNs and, on the other hand, in unprotected cells this virus induces a rapid cytopathic effect that can readily be quantified. However, as VSV may infect humans and is known to cause severe disease in a variety of animal species, this virus must be considered a biohazard. In this paper, we describe a bioassay for bovine IFN using Sendai virus, a paramyxovirus that grows readily in MDBK cells yet is released from these cells in a non-infectious form. The sensitivity and dynamic range of this assay are similar to those of the popular VSV-based IFN assay. We demonstrate that the Sendai-virus-based IFN assay permits rapid quantitation of recombinant bovine type I IFN, and also of native type I IFNs which are present in the supernatants of monocyte-derived macrophages infected with various pathogens. In view of the possible artifacts induced by viruses in samples to be assayed for IFN activity, we evaluated several methods of virus inactivation. Treatment with beta-propiolactone led to virus inactivation without affecting the bioactivity of IFNs as detected in the Sendai-virus-based assay.

A protein related to p21-activated kinase (PAK) that is involved in neurogenesis in the Drosophila adult central nervous system

Brains are organized by the developmental processes generating them. The embryonic neurogenic phase of Drosophila melanogaster has been studied in detail at the genetic, cellular and molecular level. In contrast, much of what is known of postembryonic brain development has been gathered by neuroanatomical and gene expression studies. The molecular mechanisms underlying cellular diversity and structural organisation in the adult brain, such as the establishment of the correct neuroblast number, the spatial and temporal control of neuroblast proliferation, cell fate determination, and the generation of the precise pattern of neuronal connectivity, are largely unknown. In a screen for viable mutations affecting adult central brain structures, we isolated the mushroom bodies tiny (mbt) gene of Drosophila, which encodes a protein related to p21-activated kinase (PAK). We show that mutations in mbt primarily interfere with the generation or survival of the intrinsic cells (Kenyon cells) of the mushroom body, a paired neuropil structure in the adult brain involved in learning and memory.

Test-retest reliability of the computerized DSM-IV version of the Munich-Composite International Diagnostic Interview (M-CIDI)

The structure and content of the Munich-Composite International Diagnostic Interview (M-CIDI) for the assessment of DSM-IV symptoms, syndromes, and diagnoses is described along with findings from a test-retest reliability study. A sample of 60 community respondents were interviewed twice independently by trained interviewers with an average time interval of 38 days between investigations. Test-retest reliability was good for almost all specific DSM-IV core symptom questions and disorders examined, with kappa values ranging from fair for two diagnoses--bulimia (kappa 0.55) and generalized anxiety disorder (kappa 0.45)--to excellent (kappa above 0.72) for all other anxiety disorders and alcohol use disorders. Test-retest reliability for age of onset and time-related questions was fairly consistently high (intra-class correlation values of 0.79 or above), with one notable exception: the assessment of disorders with onset before puberty. We concluded that the M-CIDI is acceptable for respondents, efficient in terms of time needed for and ease of administration, and reliable in terms of consistency of findings over time periods of at least 1 month.

Prevalence of antibodies against virus-like particles of Epidermodysplasia verruciformis-associated HPV8 in patients at risk of skin cancer

There is increasing evidence for widespread occurrences of infection with Epidermodysplasia verruciformis-related human papillomaviruses, both in the general population and in immunosuppressed patients. In order to test for the prevalence of antibodies directed against the native L1 epitopes exposed on the surface of the virions, we have established an IgG-specific enzyme-linked immunosorbent assay with L1 virus-like particles of the Epidermodysplasia verruciformis-specific human papillomavirus 8 as antigen to screen 567 representative serum samples from the general population and immunosuppressed/dermatologic patients. Among healthy European donors (n = 210), 7.6% were found to be seropositive. In a group of renal transplant recipients (n = 185) the antibody prevalence was elevated to 21.1%, irrespective of the presence or absence of skin cancer. High positivity rates could be detected among (i) immunocompetent patients with nonmelanoma skin tumors (45.6%, n = 79) and (ii) Psoralene/UVA treated psoriasis patients (42.9%, n = 42). In contrast, anti-human papillomavirus 8-virus-like particle antibodies were found in only 6.8% of Hodgkin lymphoma patients (n = 44).

[YY1 and its repressive effect on human papillomavirus 16 early promoter P97 existed widely among human epithelial cell lines]

Cellular transcription factor YY1 represses the activity of early promoter P97 of HPV 16. Removal of the specific binding sites for YY1 in HPV 16 LCR can increase the P97 activity. To analyse the expression of YY1 and the existence of the activation effect on P97 due to removing YY1 binding sites in the LCR region, we extracted nuclear proteins from four cervical cancer cell lines and two human keratinocytes. EMSA assays were carried out in vitro. At the same time, we transiently transfected the luciferase reporter plasmids, which contain HPV 16 reference and mutated LCR sequences, respectively, into the different cells and determined the luciferase expressions. The results showed that all the analysed cell lines contained biologically functional YY1 proteins. No remarkable difference in the concentration of native YY1 proteins could be detected among the tested cells. Removal of YY1 binding sites in HPV 16 LCR could elevate P97 activity in several analysed cell lines, including normal human primary kerationcytes from foreskin. It suggests that YY1 regulatory system exists widely in human epithelial cell lines. We also found that the transcription activator NF1 was more highly expressed in C33a cell than in HT3 cell, indicating an unevenly distribution of functional proteins in various cell lines.

Point mutations in SP1 motifs in the upstream regulatory region of human papillomavirus type 18 isolates from cervical cancers increase promoter activity

Evidence of the functional significance of two naturally occurring mutations at nt 40 or 41 in the Sp1 motif in the promoter proximal segment of the upstream regulatory region (URR) of human papillomavirus (HPV) type 18 is presented. In electrophoretic mobility shift assays, Sp1 protein bound more efficiently to the Sp1 mutant motifs than to the prototype; while in both HeLa and HT3 cells, luciferase activity controlled by the mutant URRs was upregulated 2- and 3-fold, or 4- and 6-fold, in comparison with the prototype URR or HeLa cell-derived URR respectively. The HeLa URR represents a more appropriate baseline for promoter activity, containing a series of point mutations representative of most HPV-18 cancer isolates, including one in the Yin Yang 1 (YY1) site at the P105 promoter. The effect of the Sp1 mutations was found to be largely maintained in the context of the HeLa URR containing the prototype YY1 site.

Novel human papillomavirus (HPV) DNA sequences from recurrent cutaneous and mucosal lesions of a stoma-carrier

Recent studies have demonstrated a high prevalence of human papillomavirus (HPV) types originally believed to be restricted to patients with epidermodysplasia verruciformis (EV) in benign and malignant skin tumors of the general population. Other groups detected typical mucosal HPV in skin tumors. We have investigated recurrent leukoplakial cutaneous and mucosal lesions located around the ileostoma of a woman with ulcerative colitis for the presence of HPV. Cutaneous, mucocutaneous, and mucosal ileostoma-biopsies were analyzed by three different polymerase chain reaction protocols for genital, cutaneous, and cutaneous EV-associated HPV types. Polymerase chain reaction products were cloned, sequenced, and submitted to phylogenetic analyses. HPV-DNA sequences of the EV-HPV group could be detected in all biopsies, whereas genital/mucosal or cutaneous HPV types were not found. HPV types detected comprised HPV20, HPV23, HPV38, and four putatively novel HPV types that belong to different clusters of the EV-HPV group B1. Different HPV types prevailed in cutaneous, mucocutaneous, and mucosal lesions and the number of HPV sequences found per lesion varied between one and three. Our data show the association of recurrent lesions around a stoma and at the ileum with known and novel EV-HPV types. These results emphasize the plurality of HPV and yield data for the possible transmission of cutaneous HPV to mucosal areas of the intestine.

Detection of new human papillomavirus sequences in skin lesions of a renal transplant recipient and characterization of one complete genome related to epidermodysplasia verruciformis-associated types

Human papillomavirus (HPV) DNA, originally isolated from patients suffering from the skin disease epidermodysplasia verruciformis (EV), and a growing number of related sequences have recently been detected in a high percentage of benign and malignant skin lesions of both immunosuppressed and immunocompetent people. HPV L1 DNA fragments (374-389 bp long) from a solar keratosis and a squamous cell carcinoma (SCC) of a renal transplant recipient were amplified, cloned and sequenced. In 54 clones, six different HPV sequences were identified. One of these six corresponded to the known type HPV-8 and two (RTRX3 and RTRX7) have been described previously in cutaneous lesions of immunosuppressed patients. The remaining three sequences were different from all known HPV types: an HPV-9-related sequence (77.4% identity), an RTRX2-related sequence (82.6% identity), and an HPV-22-related sequence (83.7% identity). These three sequences, representing putatively new HPV types, were named RTRX8, RTRX9 and RTRX10, respectively. RTRX7 was found in the majority of clones from both lesions. The complete genome of RTRX7 (7731 bp) was cloned as six overlapping subgenomic fragments, generated by nested PCR with DNA extracts from the SCC. RTRX7 showed a genome organization typical of HPVs associated with EV. The L1 DNA sequence differed by 15% from the corresponding region of its closest known relative, HPV-12; thus, RTRX7 can be regarded as a new HPV type. RTRX7 DNA could not be detected by Southern blot hybridization with the homologous probe, indicating that the DNA concentration was below one copy per 10 cells in the investigated SCC.

Structure, content and reliability of the Munich-Composite International Diagnostic Interview (M-CIDI) substance use sections

After reviewing currently available diagnostic assessment instruments for substance use disorders this paper describes the format and structure of the Munich-Composite International Diagnostic Interview (M-CIDI) substance disorder section. In addition, the test-retest reliability of diagnoses and criteria for nicotine, alcohol, illegal and prescription drugs, is reported. Findings obtained in community sample of adolescents and young adults indicate that the substance section is acceptable for almost all types of respondents, efficient in terms of time and ease of administration as well as reliable in terms of consistency of findings over time. The test-retest reliability over a period of an average of 1 month, as examined by two independent interviewers indicates good-to-excellent kappa values for all substance disorders assessed, with significant kappa values ranging between 0.55 for drug abuse and 0.83 for alcohol abuse. There was also fairly consistently high agreement for the assessment of single DSM-IV diagnostic criteria for abuse and dependence as well as the M-CIDI quantity-frequency and time-related questions. To conclude, although - unlike previous studies - this study was conducted in a community sample and not in patients and used considerably longer time intervals of more than a month between investigations, our M-CIDI reliability findings are at least as high as those from previous studies.

Use, abuse and dependence of prescription drugs in adolescents and young adults

Lifetime prevalence estimates of psychotropic medicine use as well as prevalence of DSM-IV prescription drug use disorders from the baseline investigation of the Early Developmental Stages of Psychopathology (EDSP) Study are presented. Use of prescription medication at some time in their life was reported by 27.4% of the respondents. Illicit use of prescription drugs, which means an intake without medical legitimation, was reported by 4.5% of the sample. The findings suggest that abuse of and dependence on prescription drugs, with most cases reporting polysubstance use, is quite rare in the 14- to 24-year-olds. DSM-IV abuse was more prevalent than dependence (0.5 vs. 0.3%). In general, women reported higher prevalence rates of prescription drug use, whereas men reported higher prevalence rates of prescription drug disorders. This result suggests that men have a higher risk to develop a substance-use-related disorder.

Immunohistology of the early course of lentivirus-induced arthritis

Caprine arthritis encephalitis (CAE) is a lentiviral infection of goats characterized by mononuclear cell infiltration of various tissues, most prominently the joints, mammary glands and, in young animals, the brain. We have investigated the early stages of arthritis induced by intracarpal and intravenous infection with molecularly cloned CAE virus. Analysis of the synovial membranes by immunohistological methods showed that the proportion of CD8+ T cells peaked around day 12 post-infection. CD4+ T cells increased to a lesser degree. The relative proportion of B cells rose steadily post-infection. At 33 days post-infection, plasma cells accounted for over one third of all inflammatory cells in the inflamed synovium. Histopathologically, the arthritic lesions in the synovial membranes closely resembled those in membranes of animals with a 2-year history of chronic arthritis. Our observations indicate that this type of short-term experimental infection is particularly suitable for studying the pathogenesis of goat lentiviral infection. In addition, our observations support the view that a predominantly humoral (type 2) immune response may contribute to the pathogenesis of CAE.

Comparison of inducible nitric oxide synthase expression in the brains of Listeria monocytogenes-infected cattle, sheep, and goats and in macrophages stimulated in vitro

The expression of inducible nitric oxide synthase (iNOS) was studied in the brains of cattle, sheep, and goat that succumbed to a natural infection with Listeria monocytogenes. The lesions in infected brains are characterized by microabscesses, perivascular cuffs, gliosis, glial nodules, and large areas of malacia. Using immunocytochemistry, we detected bacteria in microabscesses, particularly in sheep and goats, and in areas without signs of inflammation, but not in perivascular infiltrates. iNOS was expressed by macrophage (Mphi)-type cells of microabscesses and glial nodules but rarely by Mphi in areas of malacia, as determined by immunohistochemistry with iNOS-specific antibodies. iNOS was not detected in perivascular cuffs. Major histocompatibility complex class II molecules (MHC-II), another marker of cell activation, showed a different pattern of distribution. Perivascular cuffs contained high numbers of MHC-II-positive cells, including some with Mphi characteristics. Microabscesses in sheep and goats showed low expression of MHC-II, particularly in iNOS-expressing cells. In cattle, the expression of markers for activated or recruited phagocytes, the calcium-binding proteins S100A8 and S100A9 (formerly called MRP-8 and MRP-14, respectively), was largely restricted to cells showing weak or undetectable iNOS expression; iNOS-positive Mphi showed a low expression of S100A8 and S100A9. Thus, iNOS is expressed by a restricted subset of Mphi in listeric encephalitis. In cultured sheep and goat Mphi, a low proportion of cells expressed iNOS upon activation by L. monocytogenes and gamma interferon, resulting in nitrite generation at least 1 order of magnitude lower than that in similarly treated cattle Mphi. Since these species differences were much less obvious in vivo, it appears that the well-known species variation in iNOS expression by Mphi could reflect an in vitro phenomenon.

Regulatory interactions of transcription factor YY1 with control sequences of the E6 promoter of human papillomavirus type 8

Human papillomavirus type 8 (HPV-8) is a strictly cutaneous oncogenic virus known to induce malignant skin lesions in epidermodysplasia verruciformis patients. Our study shows that sequences surrounding transcription start sites of the HPV-8 oncogene E6 (nt 175-179) and comprising the presumable CCAAC and TATA boxes of the E6 promoter P175 contain a cluster of four motifs similar to the DNA recognition site of the multifunctional cellular transcription factor yin-yang 1 (YY1). Using DNase I footprinting and gel retardation tests it could be demonstrated that three of these motifs indeed act as YY1 binding sites. To test their functional relevance for P175 activity, engineered YY1 binding site mutants were analysed in the context of a P175 test vector using transient expression assays with human keratinocytes. YY1 turned out to exert both positive and negative effects upon the activity of the HPV-8 E6 promoter; binding of YY1 to a site upstream of the promoter's cap-position (BS1) activated transcription, whereas the downstream site (BS2) mediated repression. The second downstream YY1 binding site (BS3) seemed to play an auxiliary role, enhancing the negative effect of YY1 BS2. These observations define YY1 as an important cellular protein involved in the control of E6 oncogene expression of the skin-specific 'high risk' HPV-8 and emphasize the potential regulatory role of sequences located downstream of the transcription start site.

Virological treatment failure of protease inhibitor therapy in an unselected cohort of HIV-infected patients

OBJECTIVE

To determine the rate of virological treatment failure with protease inhibitor therapy in unselected patients and to assess underlying risk factors.

DESIGN AND SETTING

Retrospective study in two German tertiary care treatment centres.

PATIENTS

A total of 198 HIV-infected patients treated with protease inhibitors in 1996.

MAIN OUTCOME MEASURES

Levels of HIV RNA 1-6 months after start of treatment; definition of treatment failure of < 1 log10 reduction in plasma HIV RNA within 6 months after starting protease inhibitor therapy; multivariate analysis of risk factors for treatment failures.

RESULTS

A total of 226 treatment episodes with protease inhibitors were evaluable (saquinavir, 83; ritonavir, 47; indinavir, 96). The rate of virological treatment failure was 44% (saquinavir, 64%; ritonavir, 38%; indinavir, 30%). In a multivariate analysis, the following independent risk factors for virological failure were found: CD4 cell count, pretreatment with antiretroviral drugs (number), and protease inhibitor (compound). The relative risk reduction for each CD4 cell count increase was 0.997 (P = 0.012), 2.64 for pretreatment with one or two drugs versus no drug (P = 0.05), 2.97 for pretreatment with more than two drugs versus no drug (P = 0.05), and 4.62 for treatment with saquinavir versus indinavir (P = 0.001).

CONCLUSION

An unexpectedly high rate of virological treatment failure of protease inhibitor therapy was found in an unselected cohort of HIV-infected patients. Response to antiretroviral combination therapy in normal clinical practice may considerably differ from results of randomized clinical trials. Further studies are warranted to find optimal treatment strategies for both initial and salvage therapy.

Competitive binding of viral E2 protein and mammalian core-binding factor to transcriptional control sequences of human papillomavirus type 8 and bovine papillomavirus type 1

The promoter P7535 of human papillomavirus type 8 and the promoter P7185 of bovine papillomavirus type 1 are negatively regulated by viral E2 proteins via the promoter proximal binding sites P2 and BS1, respectively. Mutations of these E2 binding sites can reduce basal promoter activity. This suggests binding of a transcription-stimulating factor and may indicate that repression by E2 is due to competitive binding of viral and cellular proteins. A computer search revealed putative binding sites for core-binding factor (CBF; also referred to as PEA2, PEBP2, or AML), overlapping with P2 and BS1. Binding of recombinant CBF proteins to these sites was confirmed by band shift analysis. Competition of CBF and E2 protein for DNA binding was shown for both human papillomavirus type 8 and bovine papillomavirus type 1. The importance of CBF-E2 competition in E2-mediated repression could be demonstrated by comparing the E2 effect on P7185 activity in two cell lines containing different amounts of endogenous CBF. In cells with large amounts of CBF, E2 repressed P7185 wild-type constructs to the basal promoter activity of a mutant (50%) that could not bind this protein any more. In contrast, in a cell line containing small amounts of CBF, the promoter activities of constructs with wild-type and mutated CBF binding sites hardly differed and specific repression by E2 was not detectable.

Serum factors, cell membrane CD14, and beta2 integrins are not required for activation of bovine macrophages by lipopolysaccharide

The role of serum factors such as lipopolysaccharide (LPS)-binding protein (LBP) and of macrophage-expressed CD14 and beta2 integrins in the activation of bovine macrophages by LPS was investigated. Macrophage activation was determined by measuring tumor necrosis factor production, NO generation, and upregulation of procoagulant activity by LPS (Escherichia coli O55:B5) at concentrations of 100 pg/ml to 100 ng/ml. The 50% effective dose for LPS was 1 order of magnitude higher than that for activating human macrophages. Macrophages were activated by LPS in the presence of serum or in the presence of albumin demonstrated to be free of LBP. The capacity to react to LPS in the absence of LBP was not due to the acquisition of LBP during a previous culture in serum. It was then established which CD14-specific antibodies block LPS binding to monocytes. Among the CD14-specific antibodies recognizing bovine mononuclear phagocytes (60bca, 3C10, My4, CAM36, VPM65, CMRF31, and TUK4), the first four blocked the binding of LPS-fluorescein isothiocyanate to bovine monocytes at low concentrations. Anti-CD14 antibodies did not block LPS-mediated activation of bovine bone marrow-derived macrophages, monocyte-derived macrophages, and alveolar macrophages. This was observed in experiments in which anti-CD14 concentrations exceeded the 50% inhibitory dose by >30-fold (3C10 and My4) or >300-fold (60bca), as defined in the binding assay described above. Monocyte-derived macrophages from an animal deficient in beta2 integrins and control macrophages were activated by similar concentrations of LPS, suggesting that beta2 integrins are not important bovine LPS receptors. Thus, in bovine macrophages, LPS recognition pathways which are independent of exogenous LBP, of membrane-expressed CD14, and of beta2 integrins may exist.

Sequence variation in the upstream regulatory region of HPV 18 isolates from cervical cancers

This study describes sequence variation in both the enhancer and promoter segments of the upstream regulatory region (URR) of 28 human papillomavirus (HPV) type 18 isolates from cervical cancers, 25 from women treated at an Australian center and three from overseas included for comparison. No large-scale changes were found in either region. Fourteen substitutions were identified in the enhancer region with the number in individual isolates ranging from one to eight. Four substitutions impacted cellular transcription factor binding sites but there were no obvious associations with clinicopathological variables. The promoter segment was found to be more highly conserved than the enhancer, but four of the five point mutations identified involved cellular transcription factor binding motifs including a substitution of C for T at nt 104 which affected 21 samples. This change was found to impact upon a previously unrecognized Yin Yang (YY1) binding site. Electrophoretic mobility shift assays (EMSA) showed that this substitution significantly reduced protein-DNA binding and evidence was sought for its possible clinical implications. Of the 24 women with less than Stage III disease and known clinical outcome, tumor recurrence was observed in all of the 6 women whose isolates had the "prototype" T at nt 104, whereas only 8 of the 18 cancers with the mutation at this YY1 site recurred. This is the first report on URR variation in HPV 18 isolates from the South Pacific region. The study also provides initial data on diversity in the promoter region and preliminary evidence suggesting that a specific point mutation in this region may be clinically significant.

Macrophages infected with cytopathic bovine viral diarrhea virus release a factor(s) capable of priming uninfected macrophages for activation-induced apoptosis

Bovine bone marrow-derived macrophages infected with the cytopathic biotype of bovine viral diarrhea virus released an antiviral activity into the supernatant which was tentatively characterized as type I interferon because of its physicochemical properties. Such supernatants primed both infected and uninfected macrophages for decreased nitric oxide production and apoptosis in response to lipopolysaccharide. This finding strongly suggests a role of this pathway in the pathogenesis of mucosal disease, a lethal form of infection with cytopathic bovine viral diarrhea virus in which the principal lesions are located in the oral cavity and the gastrointestinal tract, which are known to contain a high concentration of endotoxin.

Human papillomavirus DNA in non-melanoma skin cancers of a renal transplant recipient: detection of a new sequence related to epidermodysplasia verruciformis associated types

The detection of human papillomavirus (HPV) types originally isolated from patients with epidermodysplasia verruciformis (EV) in skin tumors of transplant recipients may point to a role of this HPV subgroup in non-melanoma skin cancer in immunosuppressed people. We analyzed 17 formalin-fixed, paraffin-embedded biopsies of benign or malignant skin tumors of a renal transplant patient with unusually widespread cutaneous carcinomas. Using a nested polymerase chain reaction (PCR), HPV-specific DNA was demonstrated in 11 specimens (65%). Analysis of nine PCR amplification products revealed four different sequences related to EV-associated HPVs. Three sequences occurred only in one lesion. In six samples identical sequences were found that differed from all HPV sequences published to date and may therefore represent a novel EV-HPV type, preliminarily labeled RTRX7. RTRX7 was found in benign, premalignant, and malignant skin lesions. Alignments identified HPV12 as the closest relative of RTRX7, both in the DNA (81% homology) and in the amino acid sequence (84% homology).