Temporal variation in soluble human leukocyte antigen-G (sHLA-G) and pregnancy-associated plasma protein A (PAPP-A) in pregnancies complicated by gestational diabetes mellitus and in controls.

PROBLEM: To target gestational diabetes mellitus (GDM) by means of temporal variation in pregnancy-associated plasma protein A (PAPP-A) and soluble human leukocyte antigen-G (sHLA-G). METHOD OF STUDY: Retrospective analysis of PAPP-A and sHLA-G blood levels in historical samples of 112 GDM and 112 controls, drawn at first trimester, and prospective study in 18 GDM and 105 controls collected in triplicate along the pregnancy. Six hundred and sixty-five samples were analyzed. RESULTS: Gestational diabetes mellitus had significantly lower first-trimester PAPP-A concentrations than controls (2343±1519 versus 2996±1955 mU/mL, in retrospective brunch and 2490.57±1828.52 versus 3240.84±1930.69 mU/L in prospective one, P<0.001). First-trimester sHLA-G level was significantly lower in GDM than in controls (52.88±59.69 versus 66.81±50.14 ng/mL, P<0.001) and increased during gestation in diabetic women showing an opposite trend with respect to the controls. CONCLUSION: PAPP-A and sHLA-G are independent markers of GDM. Quantitative variations during pregnancy help to early unravel the onset of GDM.

The red cell distribution width (RDW): value and role in preterm, IUGR (intrauterine growth restricted), full-term infants.

OBJECTIVE: To measure the red cell distribution width (RDW) ranges at birth and to evaluate potential association with typical neonatal diseases: patent of the ductus arteriousus (PDA), bronchopulmonary dysplasia (BPD), and late-onset sepsis (LOS) mortality. METHODS: Forty-six full-term, 41 preterm, and 35 intrauterine growth restricted (IUGR) infants participated in this retrospective, observational study. RDW was measured before 3 days of life (T0) in all infants, and at first month of life (T1) in preterm/IURG patients. RESULTS: RDW% mean (standard deviation) at T0 was: 15.65 (1.18) in full-term newborns; 17.7 (2.06) in preterm; 17.45 (1.81) in IUGR. A negative correlation (r = -0.51; P < 0.001) between RDW and gestational age was found. RDW at T1 was: 17.25 (2.19) in the preterm group; 17.37 (2.56) in IUGR group. Fourteen preterm infants reported: 12 PDA, 5 LOS, 4 BPD, and 3 died; 10 IUGR infants had: 4 PDA, 6 LOS, 3 BPD, and 1 died. RDW of IUGR infants suffering from those pathologies was not statistically different compared with unaffected infants, while preterm newborns with pathologies reported higher RDW: PDA vs. PDA absent: P = 0.008 at T0; P < 0.002 at T1. BPD vs. BPD absent: P < 0.005 at T1. LOS vs. LOS absent: P < 0.005 at T0. RDW in preterm/IUGR population was associated with early mortality, T0: dead 21.2 (2.7) vs. alive 16.7 (1.7), P < 0.0001. CONCLUSION: RDW and gestational age at birth were negatively correlated. High RDW resulted to be an indication of risk for critical newborns. This parameter can be inexpensively and routinely verified and further studies are required to confirm its prognostic role in neonatal pathologies.

Fetal human cytomegalovirus transmission correlates with delayed maternal antibodies to gH/gL/pUL128-130-131 complex during primary infection.

Primary human cytomegalovirus (HCMV) infections during pregnancy are associated with a high risk of virus transmission to the fetus. To identify correlates of intrauterine HCMV transmission, serial serum samples from HCMV transmitter and non-transmitter pregnant women with primary HCMV infection were analyzed for the presence of neutralizing antibodies against different glycoproteins and glycoprotein complexes, which are known to mediate entry into distinct types of host cells. Neutralizing activity was detected in the sera early after primary infection; absorption with a soluble pentameric complex formed by gH/gL/pUL128-131, but not with gH/gL dimer or with gB, abolished the capacity of sera to neutralize infection of epithelial cells. Importantly, an early, high antibody response to pentamer antigenic sites was associated with a significantly reduced risk of HCMV transmission to the fetus. This association is consistent with the high in vitro inhibition of HCMV infection of epithelial/endothelial cells as well as cell-to-cell spreading and virus transfer to leukocytes by anti-pentamer antibodies. Taken together, these findings indicate that the HCMV pentamer complex is a major target of the antibody-mediated maternal immunity.

Serum antibody response to the gH/gL/pUL128-131 five-protein complex of human cytomegalovirus (HCMV) in primary and reactivated HCMV infections.

BACKGROUND: Recently, a new human cytomegalovirus (HCMV) glycoprotein complex has been identified and potentially proposed as a vaccine. OBJECTIVE: The aim of this study was to determine whether the HCMV gH/gL/pUL128-pUL130-pUL131 (gH/gL/pUL128-131) 5-protein (pentameric) complex (which has been recently found to be indispensable for the infection of endothelial and epithelial cells) is able to elicit a consistent antibody response in both primary and reactivated HCMV infections. STUDY DESIGN: The antibody response was determined by both indirect immunofluorescence (IFA) and ELISA, using fixed (IFA) or lysed (ELISA) epithelial (ARPE-19) cells infected with one or more adenoviral vectors, each carrying one HCMV gene and, in parallel, with a control adenovirus vector. RESULTS: The specificity of results was determined by the reactivity of human neutralizing mAbs recognizing two, three, or four proteins of the complex. In 14 cases of primary infection, an IgG antibody seroconversion to the UL128-131 gene products was consistently detected within 2-4 weeks after onset of infection, while antibodies persisted for at least 12 months. The IgG antibody response to UL128-131 gene products was generally superior to the response to gH and appeared to follow the neutralizing antibody response (as determined in epithelial cells). In reactivated infections, the antibody response showed a trend reminiscent of a booster response. IgG antibodies were detected in HCMV-seropositive healthy adult controls, but not in HCMV-seronegative individuals. CONCLUSIONS: The IgG antibody response to the pentameric complex could be a major target for the evaluation of the antibody response to a pentamer-based vaccine.

Comparative evaluation of eight commercial human cytomegalovirus IgG avidity assays.

BACKGROUND: The interpretation of a positive IgM antibody result to human cytomegalovirus (HCMV) in a pregnant woman is of major importance for the correct management of the pregnancy. Determination of HCMV-specific IgG avidity is considered an useful approach for distinguishing IgM antibody due to primary HCMV infection from IgM antibody elicited during non-primary infection. OBJECTIVE: Comparative evaluation of eight commercial HCMV IgG avidity assays currently available in Europe. STUDY DESIGN: A panel of 198 sequential samples collected from 65 pregnant women at 0-90, 91-180, and >180 days after the onset of primary HCMV infection was retrospectively tested by Abbott, BioMérieux, Bio-Rad, DiaSorin, Diesse, Euroimmun, Radim, and Technogenetics HCMV IgG avidity assays according to the manufacturer's instructions. RESULTS: None of the 198 samples tested yielded identical scores by the kits under evaluation. The Euroimmun and Radim assays showed the best correlation with expected results in terms of low (0-90 days), intermediate (90-180 days) and high (>180 days) avidity results, respectively. The best accuracy in diagnosing a recent (<90 days after the onset) or non-recent (>180 days after the onset) primary HCMV infection was shown by Radim followed by Euroimmun and Diesse. The best correlation with a well established in-house developed HCMV IgG avidity assay was shown by Radim. CONCLUSIONS: HCMV IgG avidity kits need to be improved and standardized. In the meantime, highly specific IgM assays are preferable for screening purposes in pregnant women.

Comparison of a new Light Diagnostics and the CMV Brite to an in-house developed human cytomegalovirus antigenemia assay.

BACKGROUND: Antigenemia, i.e. detection and quantification of human cytomegalovirus (HCMV) peripheral blood pp65-positive leukocytes, is still one of the two major assays available for diagnosis and monitoring of HCMV infections. OBJECTIVES: To evaluate the performance of a new commercial assay under development (Light Diagnostics). STUDY DESIGN: To compare the performance of the new assay with a commercial assay (CMV Brite) already available on 300 blood samples from immunocompromised patients using as a reference the original in-house developed assay. RESULTS: Although 30 blood samples gave discrepant results among the 3 antigenemia assays, the Light Diagnostics detected an overall number of antigenemia-positive blood samples (sensitivity 84%) identical to that detected by CMV Brite (sensitivity 88%) and in-house assay (91/300, 30.3%). Problems of non-specific cytoplasmic staining were encountered with the CMV Brite assay in 219/300 (73%) blood samples. CONCLUSIONS: The Light Diagnostics assay provides results comparable to those of the reference assay both in terms of specificity and sensitivity (number of pp65-positive leukocytes).

Human respiratory coronavirus HKU1 versus other coronavirus infections in Italian hospitalised patients.

BACKGROUND: Human respiratory coronavirus (hCoV) HKU1 infections were reported for the first time in 2005 in Hong Kong. OBJECTIVE: To investigate epidemiological, clinical, and diagnostic features of HKU1 infections. STUDY DESIGN: Longitudinal, prospective study from November 2005 through May 2006 in a hospitalised patient population. RESULTS: Overall, 48/426 (11.3%) patients were found to be infected by hCoV acute respiratory tract infections (ARTI). Of these, 10 (19.2%) were caused by HKU1 (6 single infections and 4 coinfections) during the period January-May 2006. Diagnosis was made by using RT-PCR for all four hCoVs, and in parallel, in-house developed group-specific monoclonal antibodies (MAbs) for HKU1 and 229E. HKU1-specific MAb was able to retrospectively identify 8 of 10 HKU1 strains detected by RT-PCR. Phylogenetic analysis showed that four HKU1 strains were genotype A and six genotype B. In HKU1-infected patients, the predominant clinical symptom was rhinorrhea (nine patients). Within group II hCoV, HKU1-infected patients had a significantly lower rate of lower ARTI compared to OC43-infected patients. CONCLUSION: HKU1 hCoV strains circulated in northern Italy during the winter-spring season 2005-2006. Both HKU1 genotypes were detected. HKU1-specific MAb may contribute to the rapid diagnosis of HKU1 infections currently performed by RT-PCR.

Detection and pathogenicity of human metapneumovirus respiratory infection in pediatric Italian patients during a winter--spring season.

BACKGROUND: Some diagnostic, epidemiological and clinical features of the recently discovered human metapneumovirus remain to be investigated. OBJECTIVES: To study the best approach for the diagnosis of human metapneumovirus infections by both conventional and molecular methods, along with the human metapneumovirus circulation rate in northern Italy and the severity of human metapneumovirus respiratory infections in a pediatric patient population. STUDY DESIGN: Nasopharyngeal aspirates (NPA) were taken from 306 pediatric patients during the winter-spring season 2003-2004, and examined for conventional respiratory viruses by direct fluorescent staining and cell culture, while human coronavirus and human metapneumovirus were sought by RT-PCR. RESULTS: RT-PCR detected human metapneumovirus in 40/306 (13.1%) children positive for respiratory viruses, with an incidence intermediate between that of respiratory syncytial virus (58 patients, 18.9%) and that of influenzavirus infections (29 patients, 9.5%). Phylogenetic analysis showed cocirculation of both human metapneumovirus types (A and B) as well as their relevant subtypes (A1-A2 and B1-B2). Clinically, human metapneumovirus was found to be second to human respiratory syncytial virus alone, as a cause of respiratory tract infections, while duration of virus excretion appeared to correlate with severity of infection, and virus load in NPA with the stage of respiratory infection. CONCLUSION: (i) Human metapneumovirus is a major viral pathogen in the Italian pediatric patient population; (ii) the severity of lower respiratory tract infections approaches that of human respiratory syncytial virus; (iii) there are preliminary indications that the duration of virus excretion may reach 2-3 weeks and that the level of viral load in NPA correlates with the clinical stage of human metapneumovirus infection.

Lymphoproliferative response in primary human cytomegalovirus (HCMV) infection is delayed in HCMV transmitter mothers.

BACKGROUND: The T cell-mediated immune response to human cytomegalovirus (HCMV) after primary infection, as well as the determinants of intrauterine transmission, are poorly understood. METHODS: Sequential peripheral blood leukocyte samples from 74 pregnant women and 29 nonpregnant individuals with primary infection were examined for HCMV-specific CD4+ T cells by cytokine flow cytometry (CFC) and lymphoproliferative response (LPR) analysis. Immunological results for 19 transmitter and 21 nontransmitter mothers were compared. RESULTS: Comparison of CFC and LPR analysis results showed that (1) there was no difference between pregnant and nonpregnant individuals; (2) HCMV-specific CD4+ T cells were detected by CFC, in the absence of an LPR to HCMV, in the great majority or the totality (according to different intervals) of samples collected from both pregnant and nonpregnant individuals during follow-up; and (3) LPR to HCMV was significantly (P<.001) lowered or delayed in transmitter mothers, compared with that in nontransmitter mothers. CONCLUSIONS: Pregnancy does not influence the HCMV-specific immune response. A dissociation between CFC response and LPR is commonly observed in patients with primary infections, and ad hoc studies aimed at understanding the mechanism(s) of the reduced LPR in transmitter mothers are warranted.

Monitoring of human cytomegalovirus (HCMV)-specific CD4+ T cell frequency by cytokine flow cytometry as a possible indicator for discontinuation of HCMV secondary prophylaxis in HAART-treated AIDS patients.

OBJECTIVE: Absolute CD4+ T cell count and human cytomegalovirus (HCMV)-specific CD4+ T cell frequency (as determined by cytokine flow cytometry, CFC) were compared for their ability to predict HCMV disease and safe discontinuation of HCMV secondary prophylaxis. STUDY DESIGN: Three groups of AIDS patients with previous nadir CD4+ T cell count <100/microl were studied. Group A included 48 HAART-treated patients with no HCMV disease. Group B included 11 HAART-treated patients with previous HCMV disease who discontinued HCMV prophylaxis. Group C included 23 HAART-treated (n = 16) or -naive (n = 7) patients with previous HCMV disease either continuing or starting HCMV prophylaxis. Patients underwent follow-up for detection of HCMV viremia or disease (groups A and B) and for discontinuation of HCMV secondary prophylaxis on the basis of either HCMV-specific or absolute CD4+ T cell count (group C). RESULTS: During follow-up, while some patients showed a stable HCMV-specific CD4+ T cell response, others had a fluctuating response (unstable responders) or showed no response at all. In detail, 13/48 group A patients were either HCMV non-responders or unstable responders and 2 of them developed HCMV viremia; 3/11 group B patients were unstable responders, none developing either HCMV viremia or disease; finally, 9 group C patients discontinued HCMV prophylaxis based on absolute CD4+ T cell count > 150 cells/microl, but in 2 of them lacking HCMV-specific response HCMV retinitis relapsed. None of the seven group C patients discontinuing HCMV prophylaxis on the basis of CFC showed HCMV disease relapse. CONCLUSIONS: CFC may support absolute CD4+ T cell count for both guiding HCMV prophylaxis discontinuation and better monitoring HCMV infection in AIDS patients with no previous HCMV disease or having discontinued HCMV prophylaxis.

In vitro selection of human cytomegalovirus variants unable to transfer virus and virus products from infected cells to polymorphonuclear leukocytes and to grow in endothelial cells.

Four human cytomegalovirus (HCMV) isolates from different clinical sources were extensively propagated in human embryonic lung fibroblasts (HELF). Plaque isolates from each of the four virus strains were evaluated for their ability to be transferred to polymorphonuclear leukocytes (PMNL) and to grow in endothelial cells (EC). While all four of the clinical strains were found to be both PMNL- and EC-tropic, variants were identified from each of the four strains that lacked both biological properties, while three of the four parental strains lost their transfer capacity before passage 50 in HELF. It was demonstrated that one of the four field isolates (VR6110) and its transfer-deficient variant were genetically related, but showed different curves of virus yield in HELF. In addition, neither the immediate-early (IE) mRNA nor the IE protein p72 were found to be transferred to PMNL before 72 h post-infection (late in infection) or in the presence of viral DNA replication inhibitors. These findings link EC and PMNL tropism and suggest that PMNL tropism is a late HCMV function.