Detection of Malawi polyomavirus sequences in secondary lymphoid tissues from Italian healthy children: a transient site of infection.

BACKGROUND: The novel Malawi polyomavirus (MWPyV) was initially detected in stool specimens from healthy children and children with gastrointestinal symptoms, mostly diarrhea, indicating that MWPyV might play a role in human gastroenteric diseases. Recently, MWPyV sequences were additionally identified in respiratory secretions from both healthy and acutely ill children suggesting that MWPyV may have a tropism for different human tissues. This study was designed to investigate the possible sites of latency/persistence for MWPyV in a cohort of healthy Italian children. METHODS: Specimens (n° 500) of tonsils, adenoids, blood, urines and feces, from 200 healthy and immunocompetent children (age range: 1-15 years) were tested for the amplification of the MWPyV LT antigen sequence by quantitative real-time PCR. Samples (n° 80) of blood and urines from 40 age-matched children with autoimmune diseases, were screened for comparison. Polyomaviruses JC/BK and Epstein-Barr Virus (EBV) were also tested as markers of infection in all samples using the same molecular technique. RESULTS: In our series of healthy children, MWPyV was detected only in the lymphoid tissues showing a prevalence of 6 % in tonsils and 1 % in adenoids, although with a low viral load. No JCPyV or BKPyV co-infection was found in MWPyV positive samples, while EBV showed a similar percentage of both in tonsils and adenoids (38 and 37 %). Conversely, no MWPyV DNA was detected in stool from babies with gastroenteric syndrome. With regards to autoimmune children, neither MWPyV nor BKPyV were detected in blood, while JCPyV viremia was observed in 15 % (6/40) of children treated with Infliximab. Urinary BKPyV shedding was observed in 12.5 % (5/40) while JCPyV in 100 % of the samples. CONCLUSIONS: The detection of MWPyV sequences in tonsils and adenoids of healthy children suggests that secondary lymphoid tissues can harbour MWPyV probably as transient sites of persistence rather than actual sites of latency.

Epidemiological and molecular assessment of a measles outbreak in a highly vaccinated population of northeast Italy.

Two distinct measles outbreaks, unrelated from the epidemiological point of view but caused by genetically related strains, occurred in the Friuli Venezia Giulia region of northeastern Italy. Forty-two cases were reported during the period April-May 2008. In the first outbreak the index case was a teacher who introduced the virus into the Pordenone area, involving eight adolescents and young adults. The other concomitant outbreak occurred in the city of Trieste with 33 cases. The containment of the epidemics can be explained by the high MMR vaccine coverage in an area where the first dose was delivered to 93·4% and the second dose to 88·3% of the target children. Phylogenetic analysis of 14 measles virus strains showed that they belonged to a unique D4 genotype indistinguishable from the MVs/Enfield.GBR/14.07 strain, probably introduced from areas (i.e. Piedmont and Germany) where this genotype was present or had recently caused a large epidemic.

C-C chemokines released by lipopolysaccharide (LPS)-stimulated human macrophages suppress HIV-1 infection in both macrophages and T cells.

Human immunodeficiency virus-1 (HIV-1) expression in monocyte-derived macrophages (MDM) infected in vitro is known to be inhibited by lipopolysaccharide (LPS). However, the mechanisms are incompletely understood. We show here that HIV-1 suppression is mediated by soluble factors released by MDM stimulated with physiologically significant concentrations of LPS. LPS-conditioned supernatants from MDM inhibited HIV-1 replication in both MDM and T cells. Depletion of C-C chemokines (RANTES, MIP-1 alpha, and MIP-1 beta) neutralized the ability of LPS-conditioned supernatants to inhibit HIV-1 replication in MDM. A combination of recombinant C-C chemokines blocked HIV-1 infection as effectively as LPS. Here, we report an inhibitory effect of C-C chemokines on HIV replication in primary macrophages. Our results raise the possibility that monocytes may play a dual role in HIV infection: while representing a reservoir for the virus, they may contribute to the containment of the infection by releasing factors that suppress HIV replication not only in monocytes but also in T lymphocytes.

Gut microbiota characterisation in obese patients before and after bariatric surgery.

Intestinal microbiota analysis of obese patients after bariatric surgery showed that Proteobacteria decreased after laparoscopic sleeve gastrectomy (SG), while it increased after laparoscopic gastric bypass (LGB). Comparing to normal weight (NW) patients, obese patients that were selected for SG showed an almost equal amount of Firmicutes and Bacteroidetes and the ratio was not affected by the surgery. Obese patients before LGB showed a predominance of Bacteroidetes, whose amount regained a relative abundance similar to NW patients after surgery. Obese patients before LGB showed the predominance of Bacteroides, which decreased after surgery in favour of Prevotella, a bacterium associated with a healthy diet. The bacteria detected at the highest percentages belonged to biofilm forming species. In conclusion, in this study, we found that the characterization of the gut microbial communities and the modality of mucosal colonisation have a central role as markers for the clinical management of obesity and promote the maintenance of good health and the weight loss.

Dynamics of HIV-1 mRNA expression in patients with long-term nonprogressive HIV-1 infection.

A large number of evidences indicate that progression of HIV disease is driven by an increase in viral burden. It is still unclear, however, to what extent this is contributed by the dysregulation of the molecular mechanisms governing virus gene expression at the transcriptional or posttranscriptional levels. To address this issue, several quantitative virologic parameters (including provirus transcriptional activity and splicing pattern) were analyzed in individuals with nonprogressive HIV infection and compared with those of a matched group of progressor patients. Exact quantification was achieved by a competitive PCR procedure using a multicompetitor template. Nonprogressors were characterized by striking differences in the levels of viremia, provirus copy number, and overall levels of all viral mRNA classes in peripheral blood mononuclear cells. Additionally, the transcriptional activity of the proviral DNA in these patients was mainly engaged in the production of multiprocessed transcripts, with a pattern resembling the early phases of the experimental infection. Taken together, these results show that both viral load and provirus transcription pattern are remarkably different in infected individuals nonprogressing toward overt disease, and further support the notion that disease progression is accompanied by a change in the kinetics of HIV gene expression.

Dynamics of viral replication in infants with vertically acquired human immunodeficiency virus type 1 infection.

About one-third of vertically HIV-1 infected infants develop AIDS within the first months of life; the remainder show slower disease progression. We investigated the relationship between the pattern of HIV-1 replication early in life and disease outcome in eleven infected infants sequentially studied from birth. Viral load in cells and plasma was measured by highly sensitive competitive PCR-based methods. Although all infants showed an increase in the indices of viral replication within their first weeks of life, three distinct patterns emerged: (a) a rapid increase in plasma viral RNA and cell-associated proviral DNA during the first 4-6 wk, reaching high steady state levels (> 1,000 HIV-1 copies/10(5) PBMC and > 1,000,000 RNA copies/ml plasma) within 2-3 mo of age; (b) a similar initial rapid increase in viral load, followed by a 2.5-50-fold decline in viral levels; (c) a significantly lower (> 10-fold) viral increase during the first 4-6 wk of age. All infants displaying the first pattern developed early AIDS, while infants with slower clinical progression exhibited the second or third pattern. These findings demonstrate that the pattern of viral replication and clearance in the first 2-3 mo of life is strictly correlated with, and predictive of disease evolution in vertically infected infants.

Effects of subcutaneous interleukin-2 therapy on CD4 subsets and in vitro cytokine production in HIV+ subjects.

HIV infection is characterized by the reduction of the CD4+, CD45RA+, CD26+, and CD28+ lymphocyte subsets and of the in vitro production of IL-2, IL-4, and interferon-gamma; on the contrary, chemokine production is usually increased. These abnormalities are only partially restored by antiretroviral chemotherapy. Therapy with interleukin-2 has been proposed to restore the functions of the immune system, but the mechanisms by which IL-2 exerts its activities are unknown. The aim of this study was to define the effects of rIL-2 administration on CD4+, CD45RA+, CD45R0+, and CD26+ lymphocytes and on the in vitro production of IL-2, IL-4, IL-10, IFN-gamma, RANTES, and sCD30 in HIV+ patients. 10 HIV+ patients with CD4 cell counts between 200 and 500 cells/mm3 were treated with six cycles of subcutaneous recombinant IL-2 administration, in combination with zidovudine and didanosine. This therapeutic regimen resulted in a remarkable increase in the number of CD4+ cells and in the prolonged reduction of the levels of viremia. CD45R01 cells were expanded during the first cycle of therapy, while CD45RA+/CD26+ cells predominated after the third cycle. At this time, the in vitro production of IL-2, IL-4, IFN-gamma, and sCD30 were significantly upregulated. These results demonstrate that rIL-2 in HIV+ patients induces the reconstitution of the CD4/CD45RA lymphocytes subtype. This expanded cell population recovered the ability to produce in vitro IL-2, IL-4, and IFN-gamma. These effects may be beneficial to HIV+ patients by improving their immune response to microorganisms or vaccines.

A Novel Panel of Serum Biomarkers for MPM Diagnosis.

Exposure to asbestos is the main cause of malignant pleural mesothelioma (MPM), a highly aggressive cancer of the pleura. Since the only tools for early detection are based on radiological tests, some authors focused on serum markers (i.e., mesothelin). The aim of this study was the evaluation of new serum biomarkers to be used individually or in combination, in order to improve the outcome of patients whose disease would be diagnosed at an earlier stage. Serum and plasma were available from 43 subjects previously exposed to asbestos and 27 MPM patients, all being epithelioid type. All the new markers found differentially expressed in MPM and healthy subjects, by proteomic and genomic approaches, have been validated in the serum by the use of specific ELISA. The combined approach, using tools of genomics and proteomics, is found to be highly innovative for this type of disease and led to the identification of new serum markers in the diagnosis of MPM. These results, if confirmed in a larger series, may have a strong impact in this area, because early detection of this cancer in people at high risk could significantly improve the course of the disease and the clinical approach to an individualized therapy.

HBV, HCV, and TTV detection by in situ polymerase chain reaction could reveal occult infection in hepatocellular carcinoma: comparison with blood markers.

OBJECTIVE: To report a retrospective analysis on the presence of hepatitis B virus (HBV), hepatitis C virus (HCV), and transfusion transmitted virus (TTV) sequences in formalin fixed, paraffin embedded liver biopsies from eight patients with hepatocellular carcinoma, in comparison with blood markers. METHODS: A direct in situ polymerase chain reaction (PCR) technique was developed for the detection and localisation of genomic signals in the liver tissue. Conventional serological and molecular methods were used for blood evaluation. RESULTS: In situ PCR showed the presence of one of the three viruses (four HCV, two HBV, and one TTV) in seven of the eight patients. In addition, a co-infection with HBV and HCV was detected in one patient. HCV and HBV sequences were located in the cytoplasm and the nucleus, respectively. When compared with blood markers, these findings were compatible with one occult HBV and two occult HCV infections. CONCLUSIONS: These findings provide further evidence for occult HBV and HCV infections in cancerous tissues from patients with hepatocellular carcinomas. In situ PCR could be an additional tool for evaluating the viral aetiology of hepatocellular carcinoma alongside conventional diagnostic procedures.

HPV genotyping and HLA II analysis in a pedigree study of pediatric RRP: preliminary results.

OBJECTIVE: This preliminary pedigree study aims at the evaluation of HPV infection and HLA class II alleles as predictive markers in pediatric RRP. METHODS: We investigated for HPV genotyping and HLA class II polymorphisms all the components of family nucleus where we detected a child born to an HPV infected mother and suffering from RRP. RESULTS: HPV 11 was detected both in the laryngeal biopsies of two of the three affected babies and in the cervical smear of their mothers. The third child was positive for HPV 6 while his mother harboured a double HPV 6-16 infection. In one family, the HLA-DQB1*0501 allele exerted its protective role. The HLA-DQB1*0301 allele, commonly associated to a high grade of cervical neoplasia and HPV infection, was present in homozygous in one mother and her child. The same allele was found, though in a heterozygous form, in the third patient too. CONCLUSION: Our report is the first attempt to use the pedigree study for the evaluation of HLA class II alleles and HPV infection related to pediatric RRP. This approach could identify genetic markers that may influence disease predisposition and the severity of HPV infection.

Chemokines involved in the early inflammatory response and in pro-tumoral activity in asbestos-exposed workers from an Italian coastal area with territorial clusters of pleural malignant mesothelioma.

OBJECTIVES: Immune mediators are likely to be relevant for the biological response to asbestos exposure. The aim of this study was to investigate the association between immune mediators involved in inflammation, cell survival and angiogenesis, and asbestos-related diseases in workers from a coastal area of North-East Italy with a high incidence of pleural malignant mesothelioma (PMM). MATERIALS AND METHODS: A selected custom set of 12 soluble mediators was evaluated with a Luminex platform in sera, pleural fluid and mesothelioma biopsies from 123 asbestos-exposed workers (38 free from pleural-pulmonary disorders, 46 with non-malignant asbestos diseases, 39 with PMM) and in sera from 33 healthy controls from the same territorial area. RESULTS: Increased immune mediator concentrations were observed in the sera of the asbestos-exposed workers compared to controls for human fibroblast growth factor (FGF-b), vascular endothelial growth factor (VEGF), CCL5 (RANTES), CXCL10 (IP-10), CLEC11A (SCGF-b), CCL27 (CTACK), CCL11 (EOTAXIN), IL-5 and IL-6 (p<0.001). The chemokines IP-10 and RANTES were associated with the severity of asbestos-related diseases. In the workers with PMM, the immune proteins secreted by mesothelioma biopsies showed detectable levels of RANTES, VEGF, and IP-10. In the same workers with PMM, a significant relationship between serum and pleural fluid concentrations was found for RANTES alone. CONCLUSIONS: Occupational exposure to asbestos seems to drive the production of specific growth factors dually involved in the early inflammatory response and in pro-tumoral activity before clinical evidence of related disorders, suggesting that their over-expression may precede the onset of asbestos-related diseases. These findings suggest that some chemokines may have a prognostic role in the progression of asbestos-related diseases and could be used for the health surveillance of either workers with an occupational history of asbestos exposure or patients affected by non-malignant asbestos-related diseases.

Quantitative dynamics of HIV type 1 expression.

A competitive PCR and RT-PCR procedure was developed for the quantification of HIV-1 nucleic acids in infected biological samples, with particular reference to the study of the kinetics of production of differently processed viral transcripts. The procedure entails the utilization of a competitor plasmid DNA (on DNA samples) or of an in vitro transcription product obtained from this plasmid (on RNA samples) and allows the quantification of proviral DNA, viral genomic RNA, and viral single- and multispliced mRNAs. Furthermore, it permits the direct standardization of these measurements to the amount of a reference cellular gene (for DNA quantification) or of a reference cellular transcript (for RNA quantification). This quantification procedure was used to monitor the dynamics of HIV-1 transcriptional activation in the latently infected U1 monocytic cell line after stimulation with phorbol-12-myristate-13-acetate, and in experimentally infected peripheral blood lymphocytes. Despite the biological differences between the two experimental systems, in both cases production of infectious virus is accompanied by a remarkable increase in the levels of unspliced viral mRNAs (rising up to 20,000 fold in U1 cells) and by a consequent switch in the abundance of the differently spliced transcript classes. These observations reinforce the notion that the control of infection is subjected also to posttranscriptional events and prompts for quantitative evaluation of HIV-1 transcript class abundance in infected individuals to define potential markers for disease progression.

The effects of antineoplastic chemotherapy on HIV disease.

Six patients with human immunodeficiency virus (HIV)-associated non-Hodgkin lymphoma receiving chemotherapy (CT) with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) plus granulocyte colony-stimulating factor were sequentially monitored to study the effects of these treatments on their immunologic status (CD4 and CD8 cell counts) and on HIV plasma viremia. We show that mean CD4 cell counts declined significantly after the third cycle of CT (187 +/- 117/microliters before CT versus 92.4 +/- 60/microliters; p = 0.04) and remained significantly reduced 4 months after completion of CT. Modifications of CD8 cell counts were not statistically significant. The effects of CT on plasma viremia, as measured by a competitive polymerase chain reaction technique, were delayed until the fourth cycle, when an increase of viral load ranging from 0.6 to 2 logs (p = 0.027) was observed. After this point, viremia returned to baseline levels, with the exception of two patients who later developed opportunistic infections and one who underwent disease progression. These results suggest that, contrary to CD4 cell counts, plasma viremia could be a faithful surrogate marker for monitoring of HIV disease progression in patients undergoing CT.

Dynamics of provirus load and lymphocyte subsets after interleukin 2 treatment in HIV-infected patients.

The association of antiretroviral agents plus interleukin 2 (IL-2) represents an efficient approach to the treatment of HIV+ subjects. While the effects of IL-2 on the immune system have been investigated, little is known concerning its impact on HIV dynamics. Two antiretroviral drugs control HIV viremia, but have minimal effects on the proviral load, a predictor of disease progression and response to therapy. The aim of this study was to define the effect of rIL-2 on HIV proviral copy numbers and its relationship to changes in CD4+ and CD8+ subsets. Twelve HIV+ patients with CD4 cell counts between 200 and 500 cells/mm3 were treated with six cycles of subcutaneous rIL-2, in combination with zidovudine and didanosine. This regimen resulted in a rapid and durable decrease in proviral load in the peripheral blood, in an increase in CD8+ lymphocytes, and in the emergence of a CD4+CD45RA+ T subset. These results demonstrate that the rationale for IL-2 administration to HIV+ patients may depend not only on its effects on the immune system, but also on the reduction of the number of infected cells, reinforcing the notion that IL-2 can have a favorable impact on the natural history of HIV infection.

Direct in situ PCR allows rapid and sensitive detection of high risk human papillomavirus in cytologic specimens and formalin-fixed paraffin tissues by fluorescent labelling.

We developed a rapid, sensitive and robust high risk human papillomavirus (HR HPV) detection protocol based on direct in situ PCR technology and fluorochrome-modified nucleotides on cytologic specimens (cell smears) and on HPV infected tissues (CIN III). Reproducible results on both cytologic specimens and paraffin-embedded tissues were obtained, providing a powerful tool for clinical investigation on HR HPV infection. Quantitative PCR performed on the same tissue sections adjacent to those used for in situ techniques allowed us to establish the sensitivity of our methods, able to detect rare copies (about 15 in our paraffin-embedded tissues) of HPV.

[Typification of HPV in clinical practice]. / Tipizzazione dell'HPV nella pratica clinica.

OBJECTIVE: To improve the sensitivity of cervical carcinoma screening and to determine the optimal management with an ASCUS Pap result we evaluated the effectiveness of combining thin layer cytologic slides (ThinPrep) and HPV DNA testing. METHODS: A total of 170 women were studied with conventional Pap smears, liquid based cytology, HPV testing and colposcopy with eventual histologic evaluation. RESULTS: The ThinPrep method yielded 12.5% more high grade lesions than did the conventional smears (and more severe diagnoses as compared to the conventional smears). HPV prevalence was significantly associated with disease status. Of 30 patients with ASCUS, HPV testing detected 100% of high grade lesions and 67% of low grade. If colposcopy had been limited to HPV+ women, 47% of case would have been spared. CONCLUSIONS: Liquid based cell collection improves sensitivity for the detection of disease. For women with ASCUS cytology, HPV DNA testing of residual specimen can identify the majority of high risk cases using a single sample.

[Maternal-fetal transmission of human papillomavirus]. / Trasmissione materno-fetale del papillomavirus umano.

AIM: Human papilloma virus (HPV) infection is one of the most frequently observed sexually-transmitted diseases (10-60% of the general population). In pregnant women, as well as accelerating the evolution of dysplasia to cervical cancer, the infection may be transmitted to the fetus during gestation or at the time of birth. Children who have been infected at birth may develop laryngeal papillomatosis during the first 5 years of life that may, in some cases, spread to the point of causing aphonia or severe respiratory obstruction. There is also the risk, although it is very low, of a carcinomatous degeneration of the larynx in these subjects during adulthood. The hypothesis of the present study was to verify the prevalence of HPV infection in a population of pregnant women and the prevalence of maternal-fetal transmission. EXPERIMENTAL DESIGN: A prospective longitudinal design lasting 11 months was used for the study. It included the collection of an endocervical biopsy from population of pregnant women using a swab that was diluted in 3 cc of physiological solution, and the collection of oropharyngeal secretions from their respective neonates using a cottonwool bud. PARTICIPANTS AND METHODS: A total of 170 pregnant women attending the Obstetric Centre of the Obstetric and Gynecological Clinic of Trieste University were recruited in the study. An endocervical biopsy was taken during the 1st and/or 2nd trimester of gestation and/or at the start of labour. Of these subjects, 23 completed all the planned biopsies and a sample of oropharyngeal secretion was collected from their neonates. TESTS: From the material obtained the presence of HPV-DNA was analysed using a PCR (protein chain reaction) technique consisting of the following steps: 1) culture of human cells expressing sequences of HPV 16 and 18 used as positive controls; 2) preservation of tissue material washed in watery 4% formalin solution; 3) amplification and viral characterization in types 6-11-16-18-31-33-52. RESULTS: Positive HPV-DNA results in at least one of the three samples collected during the various periods of gestation was 31.2%, whilst in the population in which all the planned samples were performed the frequency of positive cases was 30.4%. Positive results for HPV-DNA in oropharyngeal secretions from neonates was 21.7%. The concordance of positivity for HPV-DNA in mothers at the time of labour and in their respective neonates was 57.14%. CONCLUSIONS: The trend of infection did not reveal substantial changes during the various gestational periods in which tests were performed. The possibility of HPV-DNA transmission from mother to fetus is high, above all when the maternal PCR test is positive at the time of birth, or in the presence of a high viral load. This justifies the need to monitor this infection in pregnancy in those affected by florid genital condylomatosis or with koilocytosis on cervical cytology. It is also appropriate to check all HPV-DNA positive neonates one year after birth.

[Vertical transmission of HGV and outcome of the infected babies]. / Trasmissione verticale di HGV e storia naturale dell'infezione nei neonati.

To assess the risk of HGV mother-to-infant transmission and the clinical outcome of infected babies, we investigated 103 mother-infant couples and followed-up the infected children for 4-72 months. Twenty (19.4%) mothers were HGV-RNA positive and transmission occurred in ten (50%) babies; only one child acquired HGV and HCV infection. Maternal factors, such as history of intravenous drug use, HCV-RNA positivity, HIV coinfection, type of delivery and type of feeding were not related to HGV transmission. One HGV infected baby showed a mild hepatitis when he was also infected by Cytomegalovirus. Two babies cleared HGV within the first year of life. The HGV transmission rate is elevated but HGV infection seems to be benign, at least in a short-term follow-up.

[HHV-6, new perspectives]. / HHV-6: nuovi ruoli per un patogeno antico.

HHV-6 is the etiological agent of Exanthema subitum, and its role in human infection is well known. Recently, molecular diagnostics tools showed for HHV-6 new pathogenetic features and new clinical implication. The present paper highlights recent knowledge on HHV-6 infection and presents a number of results concerning HHV-6 infection in children who had undergone BMT and concerning the roles of endothelial cells as viral reservoir.

[Intravenous immunoglobulins in bone marrow transplantation]. / Le immunoglobuline endovena nel trapianto di midollo.

Intravenous immunoglobulins have a role also in the prevention of infections after a bone marrow transplantation. Even if a reduction of CMV pneumonia is reported it is not clear whether such an effect is due to a direct antiviral activity or it is mediated through an immune modulation that reduces GVHD and then the immune suppression. We are currently using i.v.Ig at a dose of 100 mg/kg/day within a protocol for GVHD prophylaxis after a mismatched BMT.