Human bocavirus DNA in paranasal sinus mucosa

Detection of Human Boca Virus in Gastric Adenocarcinoma

Background: Gastric cancer is one of the most common cancers worldwide. Human bocavirus (HBoV), a recently isolated virus, has been investigated for its role in many respiratory and enteric diseases. Few studies have reported its presence in solid tumors, such as lung and colon cancers. The aim of this study was to detect the presence of the HBoV1 genome in gastric adenocarcinoma, which has not yet been evaluated. Methods: Formalin-fixed paraffin-embedded (FFPE) blocks of 189 gastric tumors and 50 blocks of non-tumor gastric tissue products from elective weight reduction operations were collected. DNA extraction and real-time polymerase chain reaction (PCR) were performed for HBoV1 detection. DNA sequencing was performed using ABI Genetic Analyzer series 3500. Results: The mean age of the patients was 60±13.33 years. Tumors were more common in males than females (2.5/1). HBoV1 PCR was positive in 34 (18%) cases of GC and 10 (20%) cases of chronic gastritis (P>0.05). There was no association between age, sex, stage, and histologic subtype of the tumor and HBoV1 positivity (P>0.05) in tumor samples. The rate of intestinal metaplasia and presence of lymphoid stroma were also not more frequent in HBoV1-positive tumors (P>0.05). Conclusion: The HBoV1 can be detected in a relatively high proportion of Iranian patients with gastric cancer (18%) with no predilection for specific subtypes and no association with the degree of lymphocytic infiltration. HBoV1 can also be observed in approximately 20% of chronic gastritis cases. Further comprehensive studies are needed to elucidate the role of HBoV1 in gastric cancer development.

Influenza and Viral Pneumonia

Influenza and other respiratory viruses are commonly identified in patients with community-acquired pneumonia, hospital-acquired pneumonia, and in immunocompromised patients with pneumonia. Clinically, it is difficult to differentiate viral from bacterial pneumonia. Similarly, the radiological findings of viral infection are nonspecific. The advent of polymerase chain reaction testing has enormously facilitated the identification of respiratory viruses, which has important implications for infection control measures and treatment. Currently, treatment options for patients with viral infection are limited, but there is ongoing research on the development and clinical testing of new treatment regimens and strategies.

The Molecular Detection of Human Bocavirus (HBoV) in Colorectal Tissue with Malignant and Non-Malignant Lesions

Background: Colorectal cancer (CRC) as a worldwide human health concern is identified being a multifactorial subject that infection with specific viral particles such as oncogenic viruses is research interest. Human bocavirus (HBoV) as a recent isolated virus has been investigated in many respiratory and enteric diseases but rare studies evaluates it in tissue specimens especially in cancerous sections. The aim of this study was to detect the presence of HBoV genome and its genotyping in CRC patient’s tissue and compare the result with matched healthy control group tissue. Method: in this retrospective case-control study, CRC cases were sporadic and non-familial cancerous while control subjects had healthy or non-malignant lesions in colon tissue. A conventional-PCR performed by specific primers for HBoV VP1 gene. After sequencing of positive PCR products, raw data used for trimming and alignment by bioinformatics software CLC Main Workbench 5 and MEGA5. SPSS v.22 used for statistical calculations. Result: a total of 157 subjects were participated that 66 were diagnosed as CRC cases and 91 were non-CRC colon tissue as control group that matched by the cases. The mean age (y) ± standard deviation of each case and control groups were 59.35±14.48 and 57.21±14.66, respectively. PCR results showed there were 1.3% (2/157) HBoV positive (of each groups one was positive). Sequencing analysis showed all were HBoV-1 genotype. Conclusion: our study showed there are low rate of HBoV genome in Iranian CRC and non-CRC colon tissue. Furthermore, the predominant genotype in our studied subsets were HBoV-1 according to phylogenetic analysis.

Human polyomavirus and human papillomavirus prevalence and viral load in non-malignant tonsillar tissue and tonsillar carcinoma

Human papillomaviruses (HPVs) are an acknowledged cause of a subset of oropharyngeal cancers, especially of tonsillar cancer. Similar to HPV, some human polyomaviruses (HPyVs), such as Merkel cell polyomavirus (MCPyV), have an oncogenic potential. Recently, several novel HPyVs have been discovered. The aim of our study was to determine viral DNA prevalence and viral DNA load of 13 different HPyVs in benign and malignant tonsillar tissue and to compare the data with those found for HPV. A total of 78 biopsies of palatine tonsils with a histologic diagnosis of non-malignant disease (chronic tonsillitis, tonsillar hyperplasia, n = 40) or tonsillar squamous cell carcinoma (n = 38) were included in the study. HPyV DNA prevalence and viral load were determined by virus-specific quantitative real-time PCRs. JCPyV (1/40, 2.5%) and WUPyV (3/40, 7.5%) were only found in non-malignant tonsillar tissue. HPyV7 and HPyV10 were only detected in one (2.6%) and seven (18.4%) of the 38 cancer biopsies, respectively. Both MCPyV (8/38, 21.1 vs. 4/40, 10.0%) and HPyV6 (2/38, 5.3 vs. 1/40, 2.5%) were found more frequently in cancer samples than in non-malignant tissue, but the differences were not significant. BKPyV, KIPyV, TSPyV, HPyV9, STLPyV, HPyV12 and NJPyV were not discovered in any of the samples. HPyV loads found in HPyV DNA-positive biopsies were very low with no difference between non-malignant and malignant samples (median load <0.0001 HPyV DNA copies per beta-globin gene copy, respectively). In contrast to HPyV, high-risk HPV types (HPV16/HPV18) were found significantly more frequently in tonsillar cancers than in non-malignant tonsillar tissue (17/38, 44.7 vs. 2/40, 5.0%, p < 0.001). Furthermore, high-risk HPV DNA loads were significantly higher in the cancer compared to the non-malignant samples (median load 11.861 vs. 7 × 10^-6 HPV DNA copies per beta-globin gene copy, p = 0.012). While both HPV and HPyV may persist in tonsillar tissue, our data on HPyV DNA prevalence and load do not support a role of HPyV in tonsillar carcinogenesis, neither alone nor as co-infecting agents of HPV.

Human bocavirus: Current knowledge and future challenges

Human bocavirus (HBoV) is a parvovirus isolated about a decade ago and found worldwide in both respiratory samples, mainly from early life and children of 6-24 mo of age with acute respiratory infection, and in stool samples, from patients with gastroenteritis. Since then, other viruses related to the first HBoV isolate (HBoV1), namely HBoV2, HBoV3 and HBoV4, have been detected principally in human faeces. HBoVs are small non-enveloped single-stranded DNA viruses of about 5300 nucleotides, consisting of three open reading frames encoding the first two the non-structural protein 1 (NS1) and nuclear phosphoprotein (NP1) and the third the viral capsid proteins 1 and 2 (VP1 and VP2). HBoV pathogenicity remains to be fully clarified mainly due to the lack of animal models for the difficulties in replicating the virus in in vitro cell cultures, and the fact that HBoV infection is frequently accompanied by at least another viral and/or bacterial respiratory and/or gastroenteric pathogen infection. Current diagnostic methods to support HBoV detection include polymerase chain reaction, real-time PCR, enzyme-linked immunosorbent assay and enzyme immunoassay using recombinant VP2 or virus-like particle capsid proteins, although sequence-independent amplification techniques combined with next-generation sequencing platforms promise rapid and simultaneous detection of the pathogens in the future. This review presents the current knowledge on HBoV genotypes with emphasis on taxonomy, phylogenetic relationship and genomic analysis, biology, epidemiology, pathogenesis and diagnostic methods. The emerging discussion on HBoVs as true pathogen or innocent bystander is also emphasized.

Screening of human bocavirus in surgically excised cancer specimens

Human bocavirus (HBoV) is a prevalent virus worldwide and is mainly associated with respiratory disorders. Recently, it was detected in several disease conditions, including cancers. Colorectal cancer (CRC) is the third main cause of cancers worldwide. Risk factors that initiate cell transformation include nutritional, hereditary and infectious causes. The aim of the current study was to screen for the presence of HBoV in solid tumors of colorectal cancer and to determine the genotypes of the detected strains. Surgically excised and paraffin-embedded colorectal cancer tissue specimens from 101 male and female patients with and without metastasis were collected over the last four years. Pathological analysis and tumor stages were determined. The presence of HBoV was screened by polymerase chain reaction, and the genotype of the detected HBoV was determined by direct gene sequencing. Most of the examined specimens were adenocarcinoma with mucinous activity in many of them. Twenty-four out of 101 (23.8 %) CRC tissue specimens were found to contain HBoV-1. Low sequence diversity was recorded in the detected strains. The virus was detected in both male and female patients with an age range of 30-75 years. It is proposed that HBoV-1 could play a potential role in the induction of CRC.

Infections and coinfections by respiratory human bocavirus during eight seasons in hospitalized children

The human bocavirus (hBoV) has been identified in respiratory infections in children in a large number of studies. Despite this, the pathogenic role of the HBoV is under discussion. The main objectives of the study were: to determine the incidence of HBoV in hospitalized children; to describe the main clinical features of the positive children; and to compare the data with those from other viral infections in the same population. A prospective study was performed between 2005 and 2013 including children up to 14‐year old with respiratory infection admitted to the Severo Ochoa Hospital (Spain). Nasopharyngeal aspirates were taken from 3,275 patients and were tested for HBoV and other 15 respiratory viruses by RT‐nested PCR. HBoV was detected in 319 patients (9.9%); 80 cases as a single pathogen, and 239 cases (75%) as coinfections with other viruses. The HBoV was the fourth most common virus detected, behind respiratory syncytial virus (39.8%), rhinovirus (30.6%), and adenovirus (15%). The most common clinical diagnosis, in cases that HBoV was detected as a single pathogen was asthma exacerbation followed by pneumonia. A seasonal distribution was shown, with higher positivity rates in December and January. Children affected by HBoV were older than children infected by other viruses. Differences in terms of clinical diagnosis were found, bronchiolitis diagnosis was lower compared with the other viruses, and HBoV was associated with diagnosis of pneumonia, with increased use of antibiotics (41.8%), and radiographic infiltrates (47%). These findings could suggest a pathogenic role of HBoV in respiratory infections in children under 14 years of age. J. Med. Virol. 88:2052–2058, 2016. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Emerging respiratory viruses other than influenza

Non-influenza respiratory virus infections are common worldwide and contribute to morbidity and mortality in all age groups. The recently identified Middle East respiratory syndrome coronavirus has been associated with rapidly progressive pneumonia and high mortality rate. Adenovirus 14 has been increasingly recognized in severe acute respiratory illness in both military and civilian individuals. Rhinovirus C and human bocavirus type 1 have been commonly detected in infants and young children with respiratory tract infection and studies have shown a positive correlation between respiratory illness and high viral loads, mono-infection, viremia, and/or serologically-confirmed primary infection.

Detection of HBoV DNA in idiopathic lung fibrosis, Cologne, Germany

We report two confirmed cases of usual interstitial pneumonia (UIP) associated with infection of the human bocavirus (HBoV). In one case HBoV was identified in the bronchoalveolar lavage (BAL) during an acute exacerbation as well as post mortem in different tissues giving raise to the hypothesis that HBoV infections trigger UIP or could be a causative agent and be a systemic component in UIP. In the other case, the UIP was confirmed by radiological methods and HBoV was detected in the BAL during an acute exacerbation. Both cases give raise to the hypothesis that HBoV could be a causative agent of UIP or could contribute to its development and/or acute exacerbations.

Human bocavirus: lessons learned to date

Human bocavirus (HBoV) was identified as the second human parvovirus with pathogenic potential in 2005 in respiratory samples from children suffering from viral respiratory infections of unknown etiology. Since its first description, a large number of clinical studies have been performed that address the clinical significance of HBoV detection and the molecular biology of the virus. This review summarizes the most important steps taken in HBoV research to date and addresses open questions that need to be answered in the future to provide a better understanding of the role of a virus that is difficult to grow in cell culture and is suspected to be a pathogen, although it has not yet fulfilled Koch’s postulates.

Genomic features of the human bocaviruses

The human bocavirus (HBoV) was initially discovered in 2005 as the second pathogenic member of the parvovirus family, next to the human parvovirus B19. HBoV has since been shown to be extremely common worldwide and to cause a systemic infection in small children often resulting in respiratory disease. Three more, presumably enteric, human bocaviruses (HBoV2-4) have been identified in stool samples. Parvoviruses are assumed to replicate via their genomic terminal hairpin-like structures in a so-called 'rolling-hairpin model'. These terminal sequences have recently been partially identified in head-to-tail HBoV-PCR amplicons from clinical samples, and are most likely hybrid relics of HBoV's predecessors, namely bovine parvovirus 1 on the left-hand side and minute virus of canines on the right, shown for the first time in this article. Thereby, the replication model postulated for HBoV remains questionable as the occurrence of head-to-tail sequences is not a typical feature of the rolling-hairpin replication model. However, such episomes can also be persistent storage forms of the genome.