Search

Reactivation of BK polyomavirus (BKPyV) can cause significant kidney and bladder disease in immunocompromised patients. There are currently no effective, BKPyV-specific therapies. MAU868 is a novel, human immunoglobulin (Ig) G1 monoclonal antibody that binds the major capsid protein, VP1, of BKPyV with picomolar affinity, neutralizes infection by the 4 major BKPyV genotypes (EC 50 ranging from 0.009-0.093 μg/mL; EC 90 ranging from 0.102-4.160 μg/mL), and has comparable activity against variants with highly prevalent VP1 polymorphisms. No resistance-associated variants were identified in long-term selection studies, indicating a high in vitro barrier-to-resistance. The high-resolution crystal structure of MAU868 in complex with VP1 pentamer identified 3 key contact residues in VP1 (Y169, R170, and K172). A first-in-human study was conducted to assess the safety, tolerability, and pharmacokinetics of MAU868 following intravenous and subcutaneous administration to healthy adults in a randomized, placebo-controlled, double-blinded, single ascending dose design. MAU868 was safe and well-tolerated. All adverse events were grade 1 and resolved. The pharmacokinetics of MAU868 was typical of a human IgG, with dose-proportional systemic exposure and an elimination half-life ranging between 23 and 30 days. These results demonstrate the potential of MAU868 as a first-in-class therapeutic agent for the treatment or prevention of BKPyV disease., Competing Interests: Declaration of competing interest The authors of this manuscript have conflicts of interest to disclose as described by the American Journal of Transplantation. J. R. Abend, A. Sathe, M. B. Wrobel, M. Knapp, L. Xu, L. Zhao, P. Kim, S. Desai, A. Nguyen, X.-C. Leber, A. Hein, M. Scharenberg, J. Shaul, E. Ornelas, K. Wong, T. Pietzonka, P. Pertel, E. Traggiai, and S. J. Kovacs are or were employees of Novartis and shareholders of Novartis stock when the study was performed. L. M. Sterling was an employee of Celerion when the study was performed. MAU868 was discovered at Novartis Institutes for BioMedical Research and was then acquired by Amplyx Pharmaceuticals, Inc, which became a wholly owned subsidiary of Pfizer. MAU868 was most recently acquired and continues to be held by Vera Therapeutics., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

BK polyomavirus (BKPyV) infection causes various diseases in immunocompromised patients. Cells from human lung and kidney were infected with BKPyV and treated with commercially available intravenous immunoglobulin G (IVIG). Its effects on BKPyV replication and spread of infection were investigated, focusing on administration timing. IVIG treatment 3 hours after infection suppressed BKPyV replication assessed by real-time PCR and expression of the viral capsid protein 1 and large T-antigen. IVIG effectively reduced the number of BKPyV-infected cells 2 weeks after infection in an antibody titer-dependent manner. Virus release in the culture supernatants was not influenced by IVIG treatment 6-80 hours and 3-9 days after infection. Collectively, IVIG did not affect viral release from infected cells but inhibited the spread of infection by neutralizing the released virus and blocking the new infected cell formation, indicating greater efficacy in early localized infection. BKPyV replication resumed in IVIG-treated cultures at 7 days after IVIG removal. Early prophylactic administration of IVIG is expected to reduce the growth and spread of BKPyV infection, resulting in the reduction of infected cell lesions and prevention of BKPyV-associated diseases., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The selection of antiviral therapy for BK polyomavirus (BKPyV) infection has been extensively debated. Our study aimed to assess the efficacy and safety of various treatments for BKPyV infection., Methods: We searched PubMed, EMBASE, and Web of Science databases for relevant studies regarding drug treatments for BKPyV viremia/DNAemia published between January 1, 1970 and September 30, 2022. Two independent authors screened the published studies, extracted pertinent data, and evaluated their methodological quality. A meta-analysis was performed using the RevMan software version 4.2.2., Results: A total of 33 published studies involving 986 patients were included in the meta-analysis. Overall, therapeutic interventions comprised immunosuppression reduction alone or in combination with leflunomide, intravenous immunoglobulin (IVIG), cidofovir, or mTOR inhibitor (mTORi) therapy. The meta-analysis revealed that the efficacy of immunosuppression reduction alone for serum BKPyV clearance was 68% (95% confidence interval [CI]: 0.58-0.77; I 2  = 78%). Moreover, the efficacy of immunosuppression reduction in combination with leflunomide, cidofovir, IVIG, or mTORi therapy for serum BKPyV clearance was 61% (95% CI: 0.47-0.74; I 2  = 83%), 71% (95% CI: 0.63-0.78; I 2  = 0), 87% (95% CI: 0.82-0.93; I 2  = 45%), and 80% (95% CI: 0.59-1.00; I 2  = 58%), respectively. Compared to immunosuppression reduction alone, immunosuppression reduction combined with IVIG therapy offered a statistically significant benefit in serum BKPyV clearance (P < 0.01) with minimal adverse reactions, whereas other adjunctive drug treatments did not demonstrate considerable effects., Conclusions: Reducing immunosuppression remains the primary approach for treating BKPyV infection. Although the combination treatment with IVIG proved to be most effective, other agents might offer varied antiviral advantages of high heterogeneity, which should be substantiated in future long-term randomized controlled trials., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Introduction: BK virus associated hemorrhagic cystitis(BKV-AHC) is a serious complication observed after allogeneic stem cell transplantation and the current therapeutic options are scarce with substantial renal side effects. Although the guidelines recommend intravenous cidofovir application with caution to nephrotoxicity, there are few studies which investigated intravesical administration and reported similar therapeutic results with less renal side effects., Methods: We administered low dose, daily and consecutive (75 mg/day, for 5 days) intravesical cidofovir to 25 patients with BKV-AHC that developed after (ASCT)., Results: The response rate in our cohort was 92% and relapse was not encountered in 84% of the patient population during one year of follow-up. The median BK urine viral load significantly decreased from 260,000,000 IU/mL to 53,000,000 IU/mL after a week of treatment (p = 0.0001). Rise in serum creatinine was observed in 5 patients during treatment and post-treatment nephrotoxicity was seen in only 1 patient., Conclusions: Daily low dose intravesical cidofovir might be an effective treatment option for BKV-AHC after ASCT with favorable less systemic side effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

BK polyomavirus-associated nephropathy is one of serious complications in transplant recipients. Everolimus-a mammalian target of rapamycin inhibitor-has been shown to reduce the incidence of BK polyomavirus infection in transplant recipients. In this study, the effects of everolimus were examined on viral replication and the spread of infection in BK polyomavirus-infected cultures. BK polyomavirus replicated in renal and pulmonary cells, contrary to that in hepatocytes, and spread as diffusely scattered patterns of infected cells, unlike plaque formation through the cell-to-cell mode. BK polyomavirus is stable to heat up to 65 °C with a particle per infectivity ratio of 5000, and the replication cycle was for approximately 34 h. Everolimus administration remarkably reduced the viral replication to 20% in cells treated with 0.1-10 ng/mL, the concentration at which everolimus reached the serum of transplant recipients. In addition, it reduced the amount of viral capsid protein 1 at 5 ng/mL without reducing the ratio of viral capsid protein 1 versus β-actin, and it also retained the pattern of viral capsid protein 1 localization in the nuclei. Everolimus suppressed the number of infected cells to 32.8% during a 14-day treatment, indicating the reduction of BK polyomavirus-infected cell mass to 18.8% of untreated cultures by modifying cellular functions. The reduction in the total number of BK polyomavirus infected cells by everolimus indicates that everolimus alleviates BK polyomavirus infection, including nephropathy in transplant recipients., Competing Interests: Declaration of competing interest The authors of this manuscript have no conflicts of interest to disclose., (Copyright © 2022 Elsevier B.V. All rights reserved.)

5-aza-cytidine (5-aza-C) has been shown to be a potent human immunodeficiency virus type 1 (HIV-1) mutagen that induces G-to-C hypermutagenesis by incorporation of the reduced form (i.e., 5-aza-dC, 5-aza-dCTP). Evidence to date suggests that this lethal mutagenesis is the primary antiretroviral mechanism for 5-aza-C. To investigate the breadth of application of 5-aza-C as an antiretroviral mutagen, we have conducted a comparative, parallel analysis of the antiviral mechanism of 5-aza-C between HIV-1 and gammaretroviruses - i.e., murine leukemia virus (MuLV) and feline leukemia virus (FeLV). Intriguingly, in contrast to the hallmark G-to-C hypermutagenesis observed with HIV-1, MuLV and FeLV did not reveal the presence of a significant increase in mutational burden, particularly that of G-to-C transversion mutations. The effect of 5-aza-dCTP on DNA synthesis revealed that while HIV-1 RT was not inhibited by 5-aza-dCTP even at 100 µM, 5-aza-dCTP was incorporated and significantly inhibited MuLV RT, generating pause sites and reducing the fully extended product. 5-aza-dCTP was found to be incorporated into DNA by MuLV RT or HIV-1 RT, but only acted as a non-obligate chain terminator for MuLV RT. This biochemical data provides an independent line of experimental evidence in support of the conclusion that HIV-1 and MuLV have distinct primary mechanisms of antiretroviral action with 5-aza-C. Taken together, our data provides striking evidence that an antiretroviral mutagen can have strong potency via distinct mechanisms of action among closely related viruses, unlinking antiviral activity from antiviral mechanism of action., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Excessive production of immunoglobulins (Ig) causes endoplasmic reticulum (ER) stress and triggers the unfolded protein response (UPR). Hypergammaglobulinemia and lymphadenopathy are hallmarks of murine AIDS that develops in mice infected with the LP-BM5 murine leukemia retrovirus complex. In these mice, Th2 polarization and aberrant humoral response have been previously correlated to altered intracellular redox homeostasis. Our goal was to understand the role of the cell's redox state in Ig secretion and plasma cell (PC) maturation. To this aim, LP-BM5-infected mice were treated with I-152, an N-acetyl-cysteine and cysteamine supplier. Intraperitoneal I-152 administration (30 μmol/mouse three times a week for 9 weeks) decreased plasma IgG and increased IgG/Syndecan 1 ratio in the lymph nodes where IgG were in part accumulated within the ER. PC containing cytoplasmic inclusions filled with IgG were present in all animals, with fewer mature PC in those treated with I-152. Infection induced up-regulation of signaling molecules involved in the UPR, i.e. CHAC1, BiP, sXBP-1 and PDI, that were generally unaffected by I-152 treatment except for PDI and sXBP-1, which have a key role in protein folding and PC maturation, respectively. Our data suggest that one of the mechanisms through which I-152 can limit hypergammaglobulinemia in LP-BM5-infected mice is by influencing IgG folding/assembly as well as secretion and affecting PC maturation., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The majority of Merkel cell carcinoma, a highly aggressive neuroendocrine cancer of the skin, is associated with Merkel cell polyomavirus infection. Polyomavirus binding, internalization, and infection are mediated by glycosphingolipids. Besides receptor function, bioactive sphingolipids are increasingly recognized as potent regulators of several hallmarks of cancer. Merkel cell polyomavirus + and Merkel cell polyomavirus - cells express serine palmitoyl transferase subunits and sphingosine kinase (SK) 1/2 mRNA. Induced expression of Merkel cell polyomavirus-large tumor antigen in human lung fibroblasts resulted in upregulation of SPTLC1-3 and SK 1/2 expression. Therefore, we exploited pharmacological inhibition of sphingolipid metabolism as an option to interfere with proliferation of Merkel cell polyomavirus + Merkel cell carcinoma cell lines. We used myriocin (a serine palmitoyl transferase antagonist) and two SK inhibitors (SKI-II and ABC294640). In MKL-1 and WaGa cells myriocin decreased cellular ceramide, sphingomyelin, and sphingosine-1-phosphate content. SKI-II increased ceramide species but decreased sphingomyelin and sphingosine-1-phosphate concentrations. Aberrant sphingolipid homeostasis was associated with reduced cell viability, increased necrosis, procaspase-3 and PARP processing, caspase-3 activity, and decreased AKT S473 phosphorylation. Myriocin and SKI-II decreased tumor size and Ki-67 staining of xenografted MKL-1 and WaGa tumors on the chorioallantoic membrane. Our data suggest that pharmacological inhibition of sphingolipid synthesis could represent a potential therapeutic approach in Merkel cell carcinoma., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Recent case series describe detection of BK polyomavirus (BKV) in urinary tract cancers in kidney transplant recipients, suggesting that BKV could contribute to the development of these cancers. We assessed risk for urinary tract cancers in kidney recipients with or without treatment for presumed BKV nephropathy (tBKVN) using data from the United States Transplant Cancer Match Study (2003-2013). Among 55 697 included recipients, 2015 (3.6%) were reported with tBKVN. Relative to the general population, incidence was similarly elevated (approximately 4.5-fold) for kidney cancer in recipients with or without tBKVN, and incidence was not increased in either group for prostate cancer. In contrast, for invasive bladder cancer, incidence was more strongly elevated in recipients with versus without tBKVN (standardized incidence ratios 4.5 vs. 1.7; N = 48 cases), corresponding to an incidence rate ratio (IRR) of 2.9 (95% confidence interval [CI] 1.0-8.2), adjusted for sex, age, transplant year, and use of polyclonal antibody induction. As a result, recipients with tBKVN had borderline increased incidence for all urothelial cancers combined (renal pelvis, ureter, and bladder cancers: adjusted IRR 2.2, 95% CI 0.9-5.4; N = 89 cases). Together with reports describing BKV detection in tumor tissues, these results support an association between BKV and urothelial carcinogenesis among kidney transplant recipients., (© 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.)

BK polyomavirus (BKPyV) replication causes nephropathy and premature kidney transplant failure. Insufficient BKPyV-specific T cell control is regarded as a key mechanism, but direct effects of immunosuppressive drugs on BKPyV replication might play an additional role. We compared the effects of mammalian target of rapamycin (mTOR)- and calcineurin-inhibitors on BKPyV replication in primary human renal tubular epithelial cells. Sirolimus impaired BKPyV replication with a 90% inhibitory concentration of 4 ng/mL by interfering with mTOR-SP6-kinase activation. Sirolimus inhibition was rapid and effective up to 24 h postinfection during viral early gene expression, but not thereafter, during viral late gene expression. The mTORC-1 kinase inhibitor torin-1 showed a similar inhibition profile, supporting the notion that early steps of BKPyV replication depend on mTOR activity. Cyclosporine A also inhibited BKPyV replication, while tacrolimus activated BKPyV replication and reversed sirolimus inhibition. FK binding protein 12kda (FKBP-12) siRNA knockdown abrogated sirolimus inhibition and increased BKPyV replication similar to adding tacrolimus. Thus, sirolimus and tacrolimus exert opposite effects on BKPyV replication in renal tubular epithelial cells by a mechanism involving FKBP-12 as common target. Immunosuppressive drugs may therefore contribute directly to the risk of BKPyV replication and nephropathy besides suppressing T cell functions. The data provide rationales for clinical trials aiming at reducing the risk of BKPyV replication and disease in kidney transplantation., (© Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Intravenous immune-globulin (IVIG) use in renal transplantation has increased, with common uses including desensitization, treatment of antibody mediated rejection and adjunctive therapy for BK virus nephropathy. Although considered generally safe, potential side effects can occur in up to 23% of patients including acute kidney injury. We present a case of an unexpected cause of acute kidney injury in a renal transplant recipient following IVIG infusion. A 48-year-old nonsensitized female with end stage renal disease secondary to polycystic kidney disease received a deceased donor kidney transplant. The initial post-transplant period was unremarkable however at three years post-transplant the patient develops BK virus nephropathy. Despite a reduction in immunosuppression, graft function worsened and IVIG infusion was commenced. Immediately following the IVIG infusion, the patient develops anuric acute kidney injury necessitating hemodialysis. Renal transplant biopsy performed before and after the IVIG infusion revealed the de novo development of acute antibody mediated rejection and donor specific antibodies in the serum. Anti-HLA and donor-specific antibodies were also confirmed in a diluted sample of the IVIG preparation. We argue that the anti-HLA antibodies present in the IVIG caused an acute antibody mediated rejection in this previously nonsensitized female., (Copyright © 2013 Elsevier B.V. All rights reserved.)

BK virus, a member of the polyomavirus family, is a well-recognized cause of irreversible graft failure after kidney transplantation. Awareness of the relationship between BK infection and immunosuppression along with better understanding of its pathogenesis has contributed to increasing rates of its diagnosis. Current therapies are aimed at early diagnosis, limiting inflammation caused by the virus and elimination of the virus through different strategies. The epidemiology, pathogenesis and the different modalities of therapy available are discussed in this review along with the approach to retransplantation in the setting of graft failure from BK infection.

BK-virus is a very common polyomavirus in the global population, similar to the JC-virus responsible for Progressive Multifocal Leukoencephalopathy. BK-virus infections are an important diagnostic and therapeutic challenge in immuno-compromised patients, including: bone marrow transplant pediatric recipients in whom it may cause hemorrhagic cystitis, renal transplant recipients in whom it may cause interstitial nephropathy leading to graft loss, and in HIV infected patients in whom it may cause some types of encephalitis. Indeed, this poorly documented virus is responsible for infections with various clinical profiles, probably under-diagnosed, but could also be involved in the genesis of some cancers, especially cervix and prostate cancer. We reviewed the latest published data on this virus focusing on its possible pro-oncogenic properties. We also listed the diseases in which it is involved, with an emphasis on rare and insufficiently investigated entities. Finally, we studied the new tools available for diagnosis and treatment, and their importance in current practice., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

We have isolated a substance with anti-retroviral activity from the freshly prepared crude extract of Chelidonium majus L. (greater celandine) by 9-aminoacridine precipitation method and ion exchange chromatography using Dowex-50W/H+ resin followed by the gel filtration on Sephadex-75 column. Elemental and phenol/sulfuric acid method analyses as well as the mass spectrometry of the purified substance indicated that it may represent a low-sulfated poly-glycosaminoglycan moiety with molecular weight of approximately 3800 Da. The substance prevented infection of human CD4+ T-cell lines AA2 and H9 with HIV-1 at concentration of 25 microg/mL as well as the cell-to-cell virus spread in H9 cells continuously infected with HIV-1, as determined by the measurement of reverse transcriptase activity and p24 content in cell cultures. Furthermore, we have shown in a murine AIDS model that the treatment with purified substance significantly prevented splenomegaly and the enlargement of cervical lymph nodes in C57Bl/6 mice chronically infected with the pool of murine leukemia retroviruses. The mechanism(s) of anti-retroviral activity of this substance have to be elucidated.

BK viremia and nephritis are increasing problems in renal transplant recipients. The exact cause of the increasing prevalence of this condition remains poorly understood. Increasing prevalence has been correlated with newer immunosuppressive agents and the decline in acute rejection rates in recent years. The clinical manifestation varies from the asymptomatic state of viremia and nephritis to clinical renal dysfunction. The diagnosis of this infection is based on the combination of the presence of urinary decoy cells, virus in the urine/blood, and typical renal histological findings of interstitial nephritis. Routine post-transplant screening for BK viremia and viruria prior to the occurrence of nephritis and the reduction in immunosuppressive therapy for subjects with viremia appear to be attractive approaches. The treatment of BKV nephritis (BKVN) consists of reduction in immunosuppressive therapy and antiviral therapy with cidofovir or leflunomide or a combination of both. Approximately 30-60% of subjects with BKVN experienced irreversible graft failure. However, in recent years, the combinations of early detection, prompt diagnosis, and appropriate reduction in immunosuppressive therapy have been associated with better outcome. The pathogenesis of BK virus infection in renal transplant recipients needs to be explored. The source of BKV infection (donor as opposed to recipient), the role of host humoral, and cellular immunity to BKV, and the role of alloimmune activation in renal graft to the occurrence of nephritis are discussed in this review.

BK virus interstitial nephritis (BKVIN) is a serious complication after kidney grafting, necessitating drastic reduction of immunosuppressive therapy in order to enable viral clearance. Despite these measures, progressive graft dysfunction and graft loss occur in the majority of recipients. We diagnosed BKVIN in 21 recipients grafted between 1998 and 2004. Eight of 21 patients were treated with weekly, adjuvant low-dose cidofovir in addition to reduction of immunosuppressive therapy. BKVIN caused irreversible deterioration of graft function in all patients but renal function stabilized after antiviral treatment (creatinine clearance: 51.8-32 mL/min; p=0.001) and no graft loss occurred in cidofovir-treated recipients during 24.8 (8-41) months follow-up. Peak serum cidofovir concentrations were dose-dependent and attained approximately one-tenth of thein vitroEC50 for cidofovir against BK-virus, while pre-treatment with probenecid did not alter peak serum concentrations nor affected the incidence of nephrotoxicity. In fact, no cidofovir-related renal toxicity occurred; few patients had minor transient side effects (nausea, skin rash). In contrast, 9 of 13 patient who received no adjuvant cidofovir therapy lost their graft after median 8 (4-40) months. In this selected group of recipients with BKVIN, the use of adjuvant low-dose cidofovir therapy resulted in prolonged graft survival and stabilized graft function.

The ribonucleotide reductase inhibitor hydroxyurea (HU) has demonstrated some benefit as a component of drug cocktails for the treatment of HIV-1 infection. However, HU is notoriously myelosuppressive and often administered only as salvage therapy to patients with late-stage disease, potentially exacerbating the bone marrow toxicity of HU. In this report we have compared the antiviral effects of HU and two novel RR inhibitors trimidox (3,4,5-trihydroxybenzamidoxime) and didox (3,4-dihydroxybenzohydroxamic acid) in combination with didanosine (2,3-didoxyinosine; ddI) in the LPBM5 MuLV retrovirus model (murine AIDS). We also evaluated the effects of these drug combinations on the hematopoietic tissues of LPBM5 MuLV-infected animals. The combination of RR inhibitors and ddI was extremely effective (DX>TX>HU) in inhibiting development of retrovirus-induced disease (splenomegaly, hypergammaglobulinemia, activated B-splenocytes and loss of splenic architecture). In addition, relative levels of proviral DNA were significantly lower in combination drug-treated animals compared to infected controls. Evaluation of femur cellularity, numbers of marrow-derived myeloid progenitor cells (CFU-GM and BFU-E) and peripheral blood indices revealed that TX and DX in combination with ddI were well-tolerated. However, treatment with HU and ddI induced moderate myelosuppression. These data demonstrate that RR inhibitors in combination with ddI provide significant protection against retroviral disease in murine AIDS. Moreover, the novel RR inhibitors TX and DX appear to be more effective and less myelosuppressive than HU when administered with ddI in this model.

Human papillomavirus E6 forms a complex with p53 tumor suppressor and E6-associated protein, leading to the degradation of p53 via the ubiquitination pathway, resulting in the oncogenesis of cervical carcinomas. Several viral and cellular gene promoters were shown to be transactivated by E6 oncogene. In this study, to understand the role of transcription activity of E6 related to cervical carcinogenesis, the effect of cervical cancer drugs on E6 induced transcription activity has been elucidated. Several viral promoter (RSV, CMV, SV40, and HIV)-luciferase reporter gene constructs, and eukaryotic E6 expression vector were prepared as an E6 transcription analysis system and an exogenous E6 protein source, respectively. It was shown that the promoters of RSV, SV40, and HIV, but not CMV, were transactivated by HPV 16 E6 in cervical cancer cell line. Several known cervical cancer drugs were investigated for their effects on transcription activity of E6 in SiHa stably transfected with E6-responsive promoters. Cervical cancer drugs consistently reduced luciferase activity, in transfectants with RSV-luc (SiHa/pRSV-luc, KCTC 0427BP) E6 mRNA also. Thus, in this study, we have demonstrated that the promoters of RSV, HIV, and SV40 were transactivated by E6 in cervical cancer cells. Three cervical cancer drugs downregulated RSV-luc transcription and E6 expression by a p53 independent pathway. RSV-luc promoter analysis system could be useful for understanding the role of transcription activity of E6 related to cervical cancer and also for screening drugs against cervical cancers caused by HPV infection.

BK virus-associated nephropathy (BKVN) has become recognized as an important cause of allograft dysfunction in renal transplant recipients and despite reduction in immunosuppression, 30-40% of recipients ultimately progress to allograft loss. Cidofovir is an antiviral agent that demonstrates in vitro activity against murine polyomavirus and has been proposed for treatment of BKVN in renal allograft recipients. We describe the clinical course, renal function, serial renal histology and urine and blood viral load measurements in two consecutive patients with refractory BKVN who were treated with low-dose cidofovir (0.25 mg/kg IV). In each case, renal dysfunction and BK viral load progressed despite reduced immunosuppression, and persistent BK virus infection was documented in serial renal allograft biopsy specimens. Administration of low-dose cidofovir was associated with clearance of BK virus DNA from blood and allograft, and stabilization of renal function in both patients, without significant toxicity. These preliminary data suggest that low-dose cidofovir may be tolerated, even among renal transplant recipients with significant renal dysfunction due to BKVN. Prospective, controlled trials are warranted to further define the optimal dose, toxicity and potential role of cidofovir in renal transplant recipients with BK virus nephropathy.

Previous studies have shown inhibition of cervical cancer cell growth by treatment with high concentrations of IL-2. In the present study, we evaluated the in vitro and in vivo effects of recombinant human IL-2 on HPV-associated tumor cells (3T3-16). Treatment of 3T3-16 cells with rhIL-2 for 72 h inhibited cell growth in a dose-dependent manner and this effect was evidenced at nanomolar concentrations. These tumor cells expressed mRNA for beta and gamma subunits of the IL-2 receptor, which are required for signal transduction. In experiments to explore the effect of IL-2 on the growth of the HPV-associated tumor, mice received rhIL-2 through different routes: (i) intraperitoneal; (ii) subcutaneous, at the tumor inoculation site; or (iii) subcutaneous, distant from the tumor inoculation site. An effective antitumor response was observed only in those animals that received IL-2 at the tumor site (P<0.01). These results indicate the potential adequacy of therapeutic strategies based on local administration of rhIL-2 for cervical carcinoma, not only based on the ability of this cytokine to stimulate cellular-mediated immunity but also because of its direct effects on tumor cells.

Recently, the use of the ribonucleotide reductase (RR) inhibitor hydroxyurea (HU) in combination with nucleoside analogs has gained attention as a potential strategy for anti-HIV-1 therapy. However, appeal for the long-term use of HU in HIV-1 infection may be limited by its propensity to induce hematopoietic toxicity. We report a comparison of the efficacy and bone marrow toxicity of HU (400 and 200 mg/kg/day) with the novel RR inhibitors and free radical-scavenging compounds didox (DX; 3,4-dihydroxybenzohydroxamic acid; 350 mg/kg/day) and trimidox (TX; 3,4,5-trihydroxybenzamidoxime; 175 mg/kg/day) in the murine AIDS (LPBM5 MuLV) model of retrovirus infection. Infected mice received daily drug treatment for 8 weeks. Efficacy was determined by measuring drug effects on retroviral-induced disease progression (i.e. development of splenomegaly and hypergammaglobulinemia) and by evaluating splenic levels of proviral DNA. Bone marrow toxicity was evaluated by measuring peripheral blood indices (WBC, hematocrit and reticulocyte counts), femoral cellularity and by determining the numbers of hematopoietic progenitor cells (CFU-GM, BFU-E) per femur and spleen. Compared to infected controls receiving no drug treatment, disease progression was significantly suppressed by TX, DX and HU. However, HU was associated with mortality and induced significant hematopoietic toxicity in a time- and dose-dependent manner. Conversely, TX and DX effectively inhibited retrovirus-induced disease but did not induce hematopoietic toxicity. These results suggest that due to their reduced hematopoietic toxicity and ability to inhibit disease progression in murine AIDS, TX and DX may offer effective alternatives to HU therapy in HIV-1 infection., (Copyright 2002 Elsevier Science B.V.)

A series of nucleoside analogues were tested for in vivo anti-papillomavirus activity using the cottontail rabbit papillomavirus (CRPV) domestic rabbit model. Compounds were delivered either topically, injected into growing papillomas, or delivered subcutaneously at a site remote from the papillomas. Compounds tested included cidofovir [(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine] (HPMPC); cyclic HPMPC (cHPMPC); cyclopentenylcytosine (CPE-C); lobucavir [1R(1alpha,2beta,3alpha)]-9-[2, 3-bis(hydroxymethyl)cyclobutyl]guanine; 9-((2-phosphonylmethoxy)propyl)adenine (PMPA); adefovir 9-((2-phosphonylmethoxy)ethyl)adenine(PMEA) and cyclopropyl 9-(2-phosphonylmethoxyethyl)-2,6-diaminopurine (cyclopropylPMEDAP). Dose response curves and time-course treatments were included for most compounds tested. Strong anti-viral activity was detected using cidofovir and cHPMPC when delivered either topically or by the intralesional route. Complete cures were obtained using 1% (w/v) topical cidofovir at dosing schedules of twice daily for 8 weeks beginning at 4 weeks after CRPV infection, which represents a time when papillomas were clearly visible. Complete cures of large established papillomas were obtained by intralesional injection of 1% cidofovir three times per week for 8 weeks. Topical treatments with adefovir had strong anti-viral activity, cyclopropyl PMEDAP had moderate anti-viral activity, and CPE-C, PMPA and lobucavir showed no effects. These data indicate that certain nucleoside analogues have strong in vivo anti-papillomavirus activity and that the CRPV/rabbit model is a good model for assessing clinical responses of anti-viral treatments for patients with HPV disease.

Cidofovir, a nucleoside analog antiviral agent, has been used with moderate success in the treatment of juvenile laryngeal papillomatosis (JLP) by direct intralesional injection. We report the first case where IV cidofovir was used successfully to treat a rare but lethal multicystic lung disease complicating JLP. A 35-year-old woman with a history of JLP requiring multiple laser ablations of laryngeal papillomata each year presented with hemoptysis and was found on CT scan to have bilateral, multiple pulmonary nodules and cysts. The results of BAL fluid analysis demonstrated no evidence of malignancy, and cultures were negative for fungi and mycobacteria. Molecular DNA typing of a biopsy specimen obtained from a laryngeal papilloma confirmed infection with human papilloma virus type 11. She received 12 months of treatment with IV cidofovir followed by 9 months of combined treatmentwith IV cidofovir and subcutaneous interferon-alpha-2A. This therapeutic regime resulted in a markedly decreased requirement for surgical removal of laryngeal papillomata, and CT scanning documented the regression of the lesions in the lung parenchyma that persisted after the discontinuation of therapy. The results of this case demonstrate that cidofovir may be used successfully to treat JLP-related lung disease and suggest that further studies are warranted.

Epidermodysplasia verruciformis-associated human papillomaviruses and in particular human papillomavirus type 5 were recently shown to be highly prevalent in psoriatic skin. We have analyzed lesional skin from 54 psoriasis patients for infections with genital-specific and epidermodysplasia verruciformis-specific human papillomaviruses to define the spectrum of involved human papillomavirus types and to test if it is influenced by psoralen ultraviolet A therapy. Using polymerase chain reaction analysis we could detect human papillomavirus sequences in skin lesions of 83% of the tested patients. In contrast, human papillomavirus-DNA was only demonstrated in 19% of skin samples from 42 dermatologically healthy, immunocompetent individuals. Sequence analysis of the polymerase chain reaction amplimers revealed 14 human papillomavirus types, all belonging to the epidermodysplasia verruciformis or epidermodysplasia verruciformis-related papillomaviruses. Only in one case we identified sequences related to those of genital viruses, which, however, represented a putatively new human papillomavirus type. The most prevalent human papillomavirus type in our patient series was human papillomavirus type 36, found in 62% of the patients positive for human papillomavirus-DNA, followed by human papillomavirus type 5 (38%) and human papillomavirus type 38 (24%). Multiple infections with two to five different human papillomavirus types could be detected in skin samples of 63% of the analyzed patients. The overall human papillomavirus detection rate did not differ significantly between patients which have been subjected to psoralen ultraviolet A photochemotherapy or solely treated with topical preparations (77 vs 89%). Human papillomavirus type 5, however, could be detected significantly more frequent in lesions of psoralen ultraviolet A-treated patients (p < 0.001). Our data strongly argue for infections with epidermodysplasia verruciformis-specific papillomaviruses being an almost consistent feature of the lesional psoriatic skin and substantiate the importance of further studies to elucidate a possible involvement of human papillomaviruses in psoriasis pathology.

The synthesis, structure and spectroscopic properties on complexes with the formula [Cu(Lm)2] (1) and Cu(NO3)2(HLm)2 (2), where HLm = thiophene-2-carbaldehyde thiosemicarbazone, have been developed. The molecular structure of compound 1 consists of monomeric entities. The copper(II) ions exhibit distorted square-planar geometry with both bidentate thiosemicarbazone ligands placed in a centrosymmetric way. Metal to ligand pi-backdonation is proposed to explain several structural and spectroscopic features in these complexes. The EPR spectra of compound 1 show an orthorhombic g tensor indicating the presence of weak magnetic exchange interactions. The reaction of compound 1 with glutathione causes the reduction of the metal ion and the substitution of the thiosemicarbazone ligand by the thiol ligand. This mechanism seems to be related to the cytotoxicity of this complex against Friend Erithroleukemia cells (FLC) and melanome B16F10 cells.

The aim of this study was to treat patients for ectocervical dysplasia [cervical intraepithelial neoplasia (CIN) grades 1 and 2] and associated human papilloma virus (HPV) infections with photodynamic therapy (PDT). In 20 patients, 5-aminolevulinic acid (5-ALA, 12% w/v) was applied topically with a cervical cap 8 h prior to illumination. A thermal light source (150 W halogen lamp) emitting a broadband red light (total energy: 100 J/cm2, fluence rate: 90 mW/cm2) was used for superficial illumination of the portio. In addition, an Nd:YAG pumped dye laser (652 nm) was used to illuminate the cervical canal (total energy: 50 J/cm2, fluence rate: 300 mW/cm2). Preliminary results of follow-ups at 1, 3, 6, and 9 months posttherapy showed a cytological improvement in the grading of the PAP smears in 19 patients and the eradication of cervical HPV in 80%. These results demonstrate that ectocervical dysplasia and associated HPV infections can be treated by PDT.

A previous study by Kreider (Kreider et al., 1979) indicated that rabbit skin, which had been transplanted to immunodeficient nude mice, could be successfully infected with cottontail rabbit papillomavirus (CRPV). We have extended this observation in developing a rodent model for evaluation of compounds for activity against the papillomaviruses. In this model (called the SCID-Ra model), rabbit ear skin is transplanted to the dorsum of SCID mice and allowed to heal for 3 weeks. Infection with CRPV by scarification leads to the growth of warty lesions within 2 3 weeks in >95% of the animals. Topical and/or systemic therapy can be initiated at various times post infection (PI). Weekly lesion scores are recorded and compounds are evaluated for their ability to suppress wart growth when compared to untreated control mice. Ribavirin, which has had a suppressive effect both in the clinic for the treatment of respiratory papillomatosis and on the growth of warts in the rabbit back model, was evaluated and showed significant anti-proliferative activity with oral dosing. Both antiviral and antiproliferative compounds including podophyllin and 5-fluorouracil, which have been used clinically for the treatment of human papillomavirus (HPV) infections, were evaluated in this model. The anti-mitotic compound, Navelbine (vinorelbine tartrate), which is used for the treatment of non-small cell lung carcinoma was evaluated in this system and showed significant inhibition of wart growth with somewhat less topical cytotoxicity when compared to podophyllotoxin.

Posttransplantation lymphoproliferative disorders (PT-LPDs) represent a heterogeneous group of Epstein-Barr virus-associated lymphoid proliferations that arise in immunosuppressed transplant recipients. Some of these lesions regress after a reduction in immunosuppressive therapy, whereas some progress despite aggressive therapy. Morphological, immunophenotypic, and immunogenotypic criteria have not been useful in predicting clinical outcome. Although structural alterations in oncogenes and/or tumor suppressor genes identified in some PT-LPDs correlate with a poor clinical outcome, the presence of these alterations has not been a consistently useful predictor of lesion regression after reduction of immunosuppression. We examined 57 PT-LPD lesions obtained from 36 solid organ transplant recipients for the presence of mutations in the BCL-6 proto-oncogene using single-strand conformation polymorphism and sequence analysis, followed by correlation with histopathologic classification and clinical outcome, which was known in 33 patients. BCL-6 gene mutations were identified in 44% of the specimens and in 44% of the patients; none were identified in the cases classified as plasmacytic hyperplasia. However, mutations were present in 43% of the polymorphic lesions and 90% of the PT-LPDs diagnosed as non-Hodgkin's lymphoma or multiple myeloma. BCL-6 gene mutations predicted shorter survival and refractoriness to reduced immunosuppression and/or surgical excision. Our results suggest that the BCL-6 gene structure is a reliable indicator for the division of PT-LPDs into the biological categories of hyperplasia and malignant lymphoma, of which only the former can regress on immune reconstitution. The presence of BCL-6 gene mutations may be a useful clinical marker to determine whether reduction in immunosuppression should be attempted or more aggressive therapy should be instituted.

Background/aims: Post-transplant lymphoproliferative disorder is a well-documented complication with an incidence ranging from 2 to 10%, depending on the organ transplanted. Yet despite our increased understanding of the pathophysiology of this disease and the various treatments available, the mortality remains high at 60-80%. We present the clinical and histological features of ten adult liver transplant recipients with post-transplant lymphoproliferative disorder presenting over a 15-year period and review the therapeutic options., Methods: CD20/CD45RO immunostaining was used for T/B-cell markers; polymerase chain reaction and in-situ hybridisation for Epstein-Barr virus genome detection; kappa/lambda immunostaining and gene rearrangement analysis for clonality., Results: There were six females and four males (age range 24-56) with onset of post-transplant lymphoproliferative disorder-symptoms ranging from 3 to 72 months post transplant. Sites of post-transplant lymphoproliferative disorder included liver (n=4), lymph nodes (n=5), bone marrow (n=2), lungs (n=2), kidneys (n=2), brain, ovaries,: and pancreas (n=1). All lesions were classified as high-grade lymphoma, of B-cell lineage (9 tested); Epstein-Barr virus genome was detected in 7/10 cases. Three tumours were monoclonal; four were polyclonal and three undetermined. Treatment included immunosuppression reduction, antiviral therapy with acyclovir and/or chemotherapy (CHOP or VAPEC-B). Survival times for those patients not treated with chemotherapy were from 9 days to 30 months, whereas those receiving chemotherapy had remission times of 4 to 48 months., Conclusions: Longer-term remissions can be achieved in patients treated with systemic chemotherapy, although not without morbidity. Clonality assessment is important but treatment decisions should be based primarily on clinical features of progression, as polyclonal tumours can behave as aggressively as monoclonal tumours.

Posttransplantation lymphoproliferative disorders (PTLDs) represent an important complication of solid organ transplantation. The main causative factor of PTLDs seems to be the intensity and type of immunosuppressive therapy and the frequent occurrence of Epstein-Barr virus infection. PTLDs that are disseminated at diagnosis or present late after transplantation generally share an unfavorable prognosis and are unlikely to regress in response to reduction in immunosuppressive therapy. We describe a case of cutaneous B-cell lymphoma occurring 4 years after heart transplantation in which molecular analysis revealed a monoclonal pattern of Epstein-Barr virus infection and immunoglobulin gene rearrangement. In spite of its monoclonal nature and late occurrence, the lymphomatous lesions regressed completely after antiviral treatment and a reduction in immunosuppressive therapy.

Human herpesvirus-6 (HHV-6), human herpesvirus-7 (HHV-7), Epstein-Barr virus (EBV), and human cytomegalovirus (CMV) DNA were repeatedly assayed in peripheral blood leukocytes from 37 allogeneic bone marrow transplant (BMT) patients by polymerase chain reaction. Before BMT, HHV-6 DNA was detected in 8 (22%) patients. HHV-7, EBV, and CMV DNA were detected in 21 (57%), 10 (27%), and 1 (3%) patient, respectively. After BMT, HHV-6 DNA was detected in 26 (70%), HHV-7 in 21 (57%), EBV in 28 (76%), and CMV in 21 (57%) patients. Thirty-two (87%) patients were positive with more than one virus. HHV-6, HHV-7, and EBV DNA were found earlier than CMV DNA in most patients after BMT. The proportions of HHV-6-positive samples during the first 3 months after BMT were higher in the patients with either delayed granulocyte engraftment (P = .04, Fisher's exact test) or delayed platelet engraftment (P = .001, Fisher's exact test). The HHV-6 DNA in samples from the patients with delayed engraftment was confirmed to be variant B. The detection of any lymphotropic herpesvirus was not related to the development of acute graft-versus-host disease (aGVHD). High-dose acyclovir (ACV) prophylaxis significantly (P < .01) reduced the proportion of HHV-6-positive samples and tended to lower HHV-6 DNA levels (P = .06). Our data indicate that HHV-6 variant B can inhibit marrow engraftment and that high-dose ACV may be beneficial to engraftment after BMT by preventing HHV-6 reactivation. No relation between the proportions of HHV-7-, EBV-, and CMV-positive samples in the first 3 months and engraftment or aGVHD was found.

Rationally designed synthetic inhibitors of retroviral proteases inhibit the processing of viral polypeptides in cultures of human T lymphocytes infected with human immunodeficiency virus type 1 (HIV-1) and therefore suppress the infectivity of HIV-1 in vitro. We have previously reported the antiviral activity in vitro of HIV-1 protease inhibitors against the C-type retrovirus Rauscher murine leukemia virus (RMuLV) and the lentivirus simian immunodeficiency virus (SIV). The same compounds which blocked the infectivity of HIV-1 also inhibited the infectivity of RMuLV and SIV in vitro. This report extends these findings by testing the antiviral activity of HIV-1 protease inhibitors in vivo in the RMuLV model. RMuLV-infected mice were treated twice a day (bid) with either an active (SKF 108922) or inactive (SKF 109273) compound for fourteen days by the intraperitoneal (i.p.) route. Compared with excipient control, SKF 108922, formulated with hydroxypropyl-beta-cyclodextrin (HPB), reduced virus-induced splenomegaly, viremia, and serum reverse transcriptase (RT) levels, while SKF 109273 was inactive. The HPB vehicle by itself enhanced replication of RMuLV. The effects of changing the formulation and the route of administration were examined. SKF 108922, formulated in HPB, had similar antiviral activity when administered by the i.p. or subcutaneous (SC) routes. However, SKF 108922 administered as a colloidal suspension in cholesterol sulfate (CS) had no detectable antiviral effect. Measurements of the circulating levels of the protease inhibitor in plasma explained this result. Plasma concentrations of SKF 108922 exceeded 1000 nM within 10 min after SC administration of the compound solubilized in HPB, but SKF 108922 was not detected in plasma after SC administration of the same dose formulated with CS. Information on optimal conditions for administering these agents should prove useful in guiding their clinical application Therefore, RMuLV should provide a good model for the preclinical evaluation and development of this class of agents for the treatment of HIV.

We report a new Japanese family of sialidosis type I. The sialidase activity was deficient in the lymphocytes of 2 patients (6.8% (sister) and 12.5% (brother) of control mean). However, surprisingly, using the transformed lymphocytes by EB virus, this activity was activated to 51.7% (sister) and 49.5% (brother) of control mean, respectively. Although the mechanism for this activation was not known, we discussed the possible mechanisms for this phenomenon.

Interferons exert antiviral, antiproliferative, and immunomodulatory effects on target cells. The effectiveness of interferon treatment can be followed by measuring parameters involved in interferon action. The clinical effectiveness of interferons has been proved in the human papillomavirus (HPV)-associated disease condyloma acuminatum. Because one of the most important goals in the treatment of this condition is the elimination of recurrences, it was asked whether clinically effective interferon therapy was associated with elimination of HPV DNA. The authors used a polymerase chain reaction-based method to detect the HPV from minute amounts of clinical biopsies. Human papillomavirus-transformed cell lines or cloned HPV genomes served as different copy number controls. The intensity ratio of L1 HPV and the human beta-globin (which served as an internal control) fragments was determined and used for estimation of HPV copy number in different biopsies. A direct effect of interferon treatment on HPV viral genome copies was observed in a group of responder patients, but not in the clinically resistant group. With these data, a correlation was found between virologic data and clinical findings. This method also can be used in other lesions to determine the HPV copy number and HPV type and may have value in determining the antiviral activities of other agents used in the treatment of HPV-related lesions.

Ribavirin has been reported to enhance the activity of ddI against HIV. We explored this enhancement of antiviral activity in Rauscher murine leukemia virus (RMuLV) models in vitro and in vivo. The significant finding in these studies was that combinations of the drugs exhibited virus titer reductions that were greater than would be expected if the drug interactions were simply additive. These effects were designated synergistic by the method of Prichard and Shipman (Prichard, M.N. and Shipman, C., Jr. (1990). A three-dimensional model to analyze drug-drug interaction, Antiviral Res. 14, 181-206). In addition to the antiviral synergy, we also observed some synergistic toxicity in the animal model.

The studies summarized have shown that therapy of condylomata acuminata with interferon is effective. The route of administration does not appear to influence the results; the intralesional, intramuscular, and subcutaneous routes were effective. Additional research is required to determine whether the natural interferon or recombinant product is superior. The appropriate administration schedule may also not have been attained.

Human papillomavirus (HPV) infections usually present as benign warts (e.g., condyloma acuminatum, CA) but can also be responsible for dysplasia and carcinoma. Therapeutic options include chemotherapeutic agents, cryotherapy and surgery, but all these treatments are anti-tumor, not anti-viral. Interferons (IFNs) are the only anti-viral drugs approved for the therapy of benign HPV-related lesions. While IFN-alpha, IFN-beta and IFN-gamma have all been tested against CA, most information is available on IFN-alpha which appears efficacious via a number of routes of administration, schedules and dosages with an acceptable safety profile. The highest rate of success with IFN-alpha therapy, in terms of reduced recurrence rates of CA was reported from studies in which all visible lesions were surgically removed with subsequent administration of subcutaneous local IFN-alpha. Less data is available on the efficacy of IFNs in the treatment of HPV-related dysplasia and carcinoma, but combination therapy (e.g., IFN-alpha plus retinoids for cervical carcinoma) appears promising. Future advances in control of HPV-related lesions are expected to continue to involve IFN combined with non-antiviral therapies as well as the use of exogenous inducers of IFNs and other cytokines.

Preclinical evaluation of the effectiveness of interferon (IFN) therapy on human papillomaviruses (HPV) has been hampered by the inability to propagate these viruses in cell culture. Nonetheless, interferon is used extensively in the treatment of HPV infections. Alpha interferons in particular have found a place in the treatment of anogenital disease, plantar warts, and laryngeal papillomas. While their is significant clinical evidence to suggest that interferon is useful in therapy of disease, the cellular mechanism(s) (i.e., antiviral, antiproliferative, immunomodulatory) by which IFN is able to control HPV-induced pathology is not well understood. This review focuses on experimental animal and cell culture models which are currently being used to help identify the antiviral, antiproliferative and immunomodulatory effects of IFN on HPV infection.

CTC-96, a cobalt containing complex, was tested as a putative topical therapeutic agent for the treatment of papillomavirus-induced tumors in our cottontail rabbit papillomavirus (CRPV)-rabbit model system. Following experimental infection of domestic rabbits with CRPV, CTC-96 was applied to infection sites twice daily, 5 days a week for a total of 8 weeks. Two levels of concentrations of aqueous CTC-96 were compared to placebo control-treated animals. With increasing dose of CTC-96 we observed tumors earlier, larger, and more often across eight infected sites on each animal.

The antiretroviral activity of two new lipophilic derivatives of azidothymidine (AZT), N4-hexadecyl-2'-deoxyribocytidylyl-(3',5')-3'-azido-2',3'-deoxythy midine (N4-hexadecyldC-AZT) and N4-palmitoyl-2'-deoxyribocytidylyl-(3',5')-3'-azido-2',3'-deoxythy midine (N4-palmitoyldC-AZT) was evaluated in comparison to AZT. In vitro the drugs were tested in human immunodeficiency virus 1 (HIV-1) infected CD4+ HeLa and H9 cells. The in vivo antiviral effect of these derivatives was analysed in Rauscher leukemia virus (RLV) infected mice. The derivatives were incorporated into small liposomes. In vitro both derivatives inhibited virus proliferation in both HIV-1 infected cell lines in a similar dose-responsive manner as AZT. In a plaque reduction assay, using HeLa cells, the IC50 values were 0.035 microM for AZT, 0.5 microM for N4-hexadecyldC-AZT and 4.5 microM for N4-palmitoyldC-AZT, whereas p24 antigen analysis on H9 cells gave IC50 values of 0.005 microM, 0.05 microM and 0.05 microM, respectively. RLV infected mice were treated with intermittent schedules i.p. or i.v. on days 1, 6, 11, and days 16 or 0, 3, 7, and 11 after infection. Regimens with further delayed drug application were on days 3, 7, and 11 and 7 and 11 only. While i.p. treatment with total doses of 380-1140 mg/kg free AZT resulted in 10-30% inhibition of RLV induced splenomegaly, the derivatives gave inhibitions of 37-94%. Late onset of treatment with the derivatives was significantly more effective as compared to free AZT. Intravenous treatment with N4-hexadecyldC-AZT was effective, but with AZT was inactive. The discrepancy in antiviral activity of the AZT derivatives found between the in vitro and in vivo test systems emphasizes the importance of investigating the activity of drug derivatives in vivo.

We tested the hypothesis that infiltrating leukocytes might contribute to papilloma destruction following podofilox treatment. New Zealand White (NZW) rabbits were inoculated with cottontail rabbit papillomavirus (CRPV) onto abraded areas of the dorsal skin. At 21 d after viral inoculation, 5.0% podofilox solution was applied to some papillomas, whereas others were used as controls. Three rabbits were sacrificed at each of three different periods after treatment initiation (1, 4, and 7 d). Four monoclonal antibodies (MoAbs), RG-16 (for B cells), L11/135 (specific for T cells), 2C4 (specific for class II antigen), and Ki67 (specific for proliferating cells), were used in an immunohistochemical study. All positive cells and total cells in the field were counted with an ocular grid. After 1 d of treatment, proliferation of papilloma cells was strongly suppressed in treated papillomas, but leukocytic infiltration was not altered. At 4 d and 7 d of treatment, there were substantial increases (about two to three times) in the numbers of B and T cells and class II-expressing leukocytes. The upper layers of the papillomas were highly necrotic and cell proliferation was absent in all layers. These data support the view that podofilox has a direct toxic effect on papilloma tissue. Leukocyte infiltration is not strongly associated with papilloma tissue and may not contribute to papilloma destruction.

Vulvar vestibulitis syndrome is a constellation of symptoms and findings involving and limited to the vulvar vestibule that consists of: (1) severe pain on vestibular touch to attempted vaginal entry, (2) tenderness to pressure localized within the vulvar vestibule, and (3) physical findings confined to vulvar erythema of various degrees. Histopathologic findings are consistent with a chronic, nonspecific inflammatory response that is occasionally associated with metaplasia of the minor vestibular glands. The cause is likely multifactorial, and to date the syndrome has been seen in association with subclinical human papillomavirus, chronic recurrent candidiasis, chronic recurrent bacterial vaginosis, chronic alteration of vaginal pH, and the use of chemical and destructive therapeutic agents. Therapy is directed at elimination of these symptoms. When symptoms are unrelieved, a surgical approach consisting of vestibulectomy with vaginal advancement has a high rate of success.

The past 2 decades have witnessed an alarming increase in the incidence of human papillomavirus infections. Clinically evident cases represent only a small portion of the infected population, because millions of people have subclinical or latent infection. Human papillomavirus infection is recognized as a precursor to malignancy. Thus it is important to treat clinically evident infection. Treatment is complicated by the ability of the virus to establish latent infection and the lack of an effective antiviral agent. At present treatment is limited to the destruction of obvious and intraepithelial lesions.