Polyoma virus

Merkel cell carcinoma (MCC) is a high-grade skin cancer, but spontaneous regression is observed at a markedly higher frequency than in other carcinomas. Although spontaneous regression is a phenomenon that greatly impacts treatment planning, we still cannot predict it. We previously reported on the prognostic impact of the presence or absence of tertiary lymphoid structures (TLS) and of Merkel cell polyomavirus (MCPyV) infection. To learn more about the spontaneous regression of MCC, detailed analyses were performed focusing on spontaneous regression cases...

OBJECTIVES: We investigated the efficacy of a predetermined protocol that consisted of immunosuppressive drug reduction/withdrawal and intravenous immunoglobulin administration for the treatment of polyoma BK virus nephropathy. MATERIALS AND METHODS: Patients with biopsy-proven polyoma BK virus nephropathy received a treatment regimen based on discontinuation of both calcineurin inhibitors and antiproliferative agents and switching to mTOR inhibitors accompanied by intravenous immunoglobulin administration...

OBJECTIVE: Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine neoplasm that predominantly affects elderly and immunocompromised patients. Merkel cell polyoma virus (MCPyV) is clonally integrated into the majority of MCCs and has been linked to patient outcomes, playing a central role in the pathogenesis of the disease. We aimed to assess the utility of MCPyV immunohistochemistry (IHC) in the diagnosis of MCC in cytology cell block specimens and correlating with clinicopathologic features...

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system (CNS) caused by reactivation of dormant JC polyomavirus (JCPyV). PML was mainly observed in immunocompromised individuals, such as HIV-positive patients, autoimmune disease patients, and cancer patients. Given that the presence of anti-JCPyV antibodies in serum is a risk indicator for PML development, it is essential to monitor anti-JCPyV antibody levels. In the present study, we established reporter-based single-infection neutralization assays for JCPyV and the genetically similar BK polyoma virus (BKPyV)...

OBJECTIVES: The current study aimed to examine the incidence of perioperative infections and graft viability in ABO-compatible and ABO-incompatible renal transplant recipients. METHODS: We included 643 living donor renal transplant recipients registered in the Michinoku Renal Transplant Network from 1998 to 2021. Patients were divided into the ABO-compatible and ABO-incompatible kidney transplantation groups. We compared the characteristics of the two groups and evaluated the incidence of postoperative viral infections (cytomegalovirus and BK virus), graft loss-free survival, and overall survival between the two groups...

The focal adhesion protein, Hic-5 plays a key role in promoting extracellular matrix deposition and remodeling by cancer associated fibroblasts within the tumor stroma to promote breast tumor cell invasion. However, whether stromal matrix gene expression is regulated by Hic-5 is still unknown. Utilizing a constitutive Hic-5 knockout, Mouse Mammary Tumor Virus-Polyoma Middle T-Antigen spontaneous breast tumor mouse model, bulk RNAseq analysis was performed on cancer associated fibroblasts isolated from Hic-5 knockout mammary tumors...

Infectious agents contribute significantly to the global burden of diseases through both acute infection and their chronic sequelae. We leveraged the UK Biobank to identify genetic loci that influence humoral immune response to multiple infections. From 45 genome-wide association studies in 9,611 participants from UK Biobank, we identified NFKB1 as a locus associated with quantitative antibody responses to multiple pathogens, including those from the herpes, retro-, and polyoma-virus families. An insertion-deletion variant thought to affect NFKB1 expression (rs28362491), was mapped as the likely causal variant and could play a key role in regulation of the immune response...

BACKGROUND: BKPyV virus nephropathy (BKPyVAN) is diagnosed in 5%-16% of pediatric renal transplant recipients (PRTR) and preceded by BKPyV-viruria and DNAemia. Despite the risk of irreversible transplant damage associated with BKPyVAN, evidence-based consensus guidelines for BKPyVAN prevention are still lacking. In this retrospective study, we examined the safety and efficacy of high-dose intravenous immunoglobulin (HD-IVIG) therapy for prevention of BKPyVAN in PRTR with significant BKPyV-viruria/DNAemia...

Metastasis of breast cancer cells to distant tissue sites is responsible for the majority of deaths associated with breast cancer. Previously we have examined the role of class I myosin motor protein, myosin 1e (myo1e), in cancer metastasis using the Mouse Mammary Tumor Virus-Polyoma Middle T Antigen (MMTV-PyMT) mouse model. Mice deficient in myo1e formed tumors with a more differentiated phenotype relative to the wild-type mice and formed no detectable lung metastases. In the current study, we investigated how the absence of myo1e affects cell migration and invasion in vitro, using the highly invasive and migratory breast cancer cell line, 4T1...

Polyomaviruses are widespread, with BK viruses being most common in humans who require immunosuppression due to allotransplantation. Infection with BK polyomavirus (BKV) may manifest as BK virus-associated nephropathy and hemorrhagic cystitis. Established diagnostic methods include the detection of polyomavirus in urine and blood by PCR and in tissue biopsies via immunohistochemistry. In this study, 79 patients with pathological renal retention parameters and acute kidney injury (AKI) were screened for BK polyomavirus replication by RNA extraction, reverse transcription, and virus-specific qPCR in urine sediment cells...

Surveillance of the renal allograft recipient is essential when monitoring renal function to detect the early onset of rejection and alter therapeutic treatments to treat acute rejection or other causes and improve long-term graft function. If renal function begins to deteriorate, a renal biopsy is often indicated to assess the Banff grade of potential rejection or other causes, especially in the setting of polyoma BK viral load elevation. Although BK infection in the allograft is asymptomatic, reactivation of the virus is known to be associated with the acceleration of pathologic change and a poor outcome in the allograft...

In triple-negative breast cancer (TNBC), stromal restriction of CD8+ T cells associates with poor clinical outcomes and lack of responsiveness to immune-checkpoint blockade (ICB). To identify mediators of T cell stromal restriction, we profiled murine breast tumors lacking the transcription factor Stat3, which is commonly hyperactive in breast cancers and promotes an immunosuppressive tumor microenvironment. Expression of the cytokine Chi3l1 was decreased in Stat3-/- tumors. CHI3L1 expression was elevated in human TNBCs and other solid tumors exhibiting T cell stromal restriction...

BACKGROUND: The incidence of progressive multifocal leukoencephalopathy (PML) in people living with HIV (PLWH) is 2%-4%. Currently, there is no effective therapeutic strategy for the treatment of PML in PLWH, resulting in a mortality of up to 50%. This study aimed to identify risk factors of death and prognostic markers in people living with HIV with PML. METHODS: A retrospective cohort study of AIDS-related PML individuals was conducted from January 1, 2015, to October 1, 2022, in Shanghai, China...

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease due to a lytic infection of oligodendrocytes caused by John Cunningham polyoma virus (JCV) infection. Idiopathic CD4+ T-cell lymphocytopenia (ICL) is a very rare cause of PML. METHODS: We present an individual with PML secondary to ICL treated with 3 doses of pembrolizumab, a Programmed-Death-1 Immune Checkpoint Inhibitor following with complete resolution of symptoms and conduct a review of the literature...

Human Leukocyte Antigen (HLA) is involved in both multiple sclerosis (MS) and immune response to viruses. Here we investigated the virus-HLA immunogenicity (V-HLA) of 12 viruses implicated in MS with respect to 17 HLA Class I alleles positively associated to MS prevalence in 14 European countries. Overall, higher V-HLA immunogenicity was associated with smaller MS-HLA effect, with human herpes virus 3 (HHV3), JC human polyoma virus (JCV), HHV1, HHV4, HHV7, HHV5 showing the strongest association, followed by HHV8, HHV6A, and HHV6B (moderate association), and human endogenous retrovirus (HERV-W), HHV2, and human papilloma virus (HPV) (weakest association)...

PURPOSE/OBJECTIVE(S): Post-lumpectomy radiotherapy (RT) reduces in-breast tumor recurrence by eradicating residual, occult breast cancer (BC) that may be in the mm size scale. The ability of FLASH-RT to eradicate BC relative to conventional dose rate (CONV) RT is unknown. ∼ 20Gy RT is currently used clinically for single-fraction breast IORT. Determine the effectiveness of FLASH compared to CONV in eradicating small tumors in an orthotopic, syngeneic model of BC using single-fraction 20 or 30Gy RT...

INTRODUCTION: Kidney transplant recipients (KTR) have a three-to-four-fold increased risk of developing urothelial carcinoma (UC) compared to the general population. BK polyoma virus (BKV) infection is known to affect approximately 15% of KTR. In vitro models support a potential pathogenic role for BKV in the development of UC. We describe a series of UC in kidney transplant recipients. METHODS: Electronic patient records were searched to identify KTR with UC who had undergone kidney only or simultaneous kidney and pancreas transplantation in a single UK center between 2009 and 2015...

BACKGROUND: There is no robust evidence-based data for ABO-incompatible kidney transplantation (ABOiKT) from emerging countries. METHODS: Data from 1759 living donor ABOiKT and 33 157 ABO-compatible kidney transplantations (ABOcKT) performed in India between March 5, 2011, and July 2, 2022, were included in this retrospective, multicenter (n = 25) study. The primary outcomes included management protocols, mortality, graft loss, and biopsy-proven acute rejection (BPAR)...

We report a case of a 68-year-old woman with a background of primary cerebral vasculitis, which was diagnosed two years ago. She appeared to have had a recurrence of her symptoms with new onset history of expressive dysphasia, right-sided upper limb weakness, and right-sided facial weakness during a rheumatology clinic visit. The patient was on maintenance azathioprine for her cerebral vasculitis at the time of presentation. She had received a total of 2 g of rituximab through intravenous infusion, with a two-week interval between doses...

Decoy cells that can be detected in the urine sediment of immunosuppressed patients are often caused by the uncontrolled replication of polyomaviruses, such as BK-Virus (BKV) and John Cunningham (JC)-Virus (JCV), within the upper urinary tract. Due to the wide availability of highly sensitive BKV and JCV PCR, the diagnostic utility of screening for decoy cells in urine as an indicator of polyomavirus-associated nephropathy (PyVAN) has been questioned by some institutions. We hypothesize that specific staining of different infection time-dependent BKV-specific antigens in urine sediment could allow cell-specific mapping of antigen expression during decoy cell development...