Minal M. Amin

Twist: a regulator of epithelial-mesenchymal transition in lung fibrosis.

Background Several studies have implicated viral infection as an important factor in the pathogenesis of IPF and related fibrotic lung disorders. Viruses are thought to cause epithelial cell injury and promote epithelial-mesenchymal transition (EMT), a process whereby differentiated epithelial cells undergo transition to a mesenchymal phenotype, and considered a source of fibroblasts in the setting of lung injury. We have demonstrated an association between the epithelial injury caused by chronic herpes virus infection with the murine γ-herpes virus, MHV68, and lung fibrosis. We hypothesize that EMT in this model of virus-induced pulmonary fibrosis is driven by the expression of the transcription factor Twist. Methods/Findings In vitro MHV68 infection of murine lung epithelial cells induced expression of Twist, and mesenchymal markers. Stable overexpression of Twist promoted EMT in MLE15 lung epithelial cells. Transient knockdown expression of Twist resulted in preservation of epithelial phenotype after in vitro MHV68 infection. In concordance, high expression of Twist was found in lung epithelial cells of MHV68 infected mice, but not in mock infected mice. Alveolar epithelial cells from lung tissue of idiopathic pulmonary fibrosis (IPF) patients were strongly positive for Twist. These cells demonstrated features of EMT with low expression of E-cadherin and upregulation of the mesenchymal marker N-cadherin. Finally, IPF tissue with high Twist protein levels was also positive for the herpesvirus, EBV. Conclusions/Significance We conclude that Twist contributes to EMT in the model of virus-induced pulmonary fibrosis. We speculate that in some IPF cases, γ-herpes virus infection with EBV might be a source of injury precipitating EMT through the expression of Twist.

National prevalence estimates for cytomegalovirus IgM and IgG avidity and association between high IgM antibody titer and low IgG avidity.

ABSTRACT Primary cytomegalovirus (CMV) infection of the mother during pregnancy presents risk of CMV infection of the fetus with resulting permanent disability. CMV IgM antibody is generated following primary CMV infection but also can appear during nonprimary CMV infection and is thus of limited diagnostic use by itself. In contrast, the presence of low CMV IgG avidity has been shown to be a unique and reliable serologic indicator of primary CMV infection. We measured CMV IgG and IgM antibody levels and IgG avidity in sera from a population sample of 6,067 U.S. women aged 12 to 49 years from NHANES (National Health and Nutrition Examination Survey). The CMV IgG prevalence was 58% overall and increased strongly with age. The CMV IgM prevalence was 3.0% overall and remained relatively flat across age groups. The prevalence of low IgG avidity was 2.0% overall, decreased sharply with age, and was seen mainly among IgM-positive sera. Fourteen to 18% of the CMV IgM-positive sera were low IgG avidity, presumably representing primary CMV infection. High CMV IgM antibody titer was a strong predictor of low IgG avidity. The ability to reliably identify primary CMV infection during pregnancy is important for management of the pregnancy, including possible treatment options for the fetus. Both IgM and IgG avidity measurements provide useful clinical information for evaluating primary CMV infection, although commercial tests for CMV IgG avidity are not yet widely available in the United States.

Use of Screening Dried Blood Spots for Estimation of Prevalence, Risk Factors, and Birth Outcomes of Congenital Cytomegalovirus Infection

OBJECTIVES To determine the birth prevalence of cytomegalovirus (CMV) in a population-based sample of newborns by use of dried blood spots compared with previous studies that used established detection methods, and to evaluate risk factors and birth outcomes for congenital CMV infection. STUDY DESIGN A total of 3972 newborn dried blood spots collected for the California Newborn Screening Program were tested for presence of CMV DNA. Demographic and pregnancy data were obtained from linked newborn screening and live-birth records. RESULTS CMV prevalence among newborns by maternal race and ethnicity was 0.9% for blacks, 0.8% for Hispanics, 0.6% for whites, and 0.6% for Asians. Among Hispanics (n = 2053), infants who were infected had younger mothers (23 vs 26 years, P = .03), and prevalence was higher for children with no father information provided (2.6% vs 0.6%, P = .03). Overall CMV infection was associated with low birth weight (prevalence ratios [95% CI]: 3.4 [1.4-8.5]) and preterm birth (2.7 [1.4-5.1]). CMV viral loads were inversely related to birth weight and gestational age (both P = .03). CONCLUSIONS CMV prevalence measured with dried blood spots was similar to reports using standard viral culture methods. Dried blood spots may be suitable for detection of CMV infection in newborns and warrant further evaluation. Congenital CMV infection may contribute to low birth weight and preterm birth.

Repeated measures study of weekly and daily cytomegalovirus shedding patterns in saliva and urine of healthy cytomegalovirus-seropositive children

BackgroundTo better understand potential transmission risks from contact with the body fluids of children, we monitored the presence and amount of CMV shedding over time in healthy CMV-seropositive children.MethodsThrough screening we identified 36 children from the Atlanta, Georgia area who were CMV-seropositive, including 23 who were shedding CMV at the time of screening. Each child received 12 weekly in-home visits at which field workers collected saliva and urine. During the final two weeks, parents also collected saliva and urine daily.ResultsPrevalence of shedding was highly correlated with initial shedding status: children shedding at the screening visit had CMV DNA in 84% of follow-up saliva specimens (455/543) and 28% of follow-up urine specimens (151/539); those not shedding at the screening visit had CMV DNA in 16% of follow-up saliva specimens (47/303) and 5% of follow-up urine specimens (16/305). Among positive specimens we found median viral loads of 82,900 copies/mL in saliva and 34,730 copies/mL in urine (P = 0.01), while the viral load for the 75th percentile was nearly 1.5 million copies/mL for saliva compared to 86,800 copies/mL for urine. Younger age was significantly associated with higher viral loads, especially for saliva (P < 0.001). Shedding prevalence and viral loads were relatively stable over time. All children who were shedding at the screening visit were still shedding at least some days during weeks 11 and 12, and median and mean viral loads did not change substantially over time.ConclusionsHealthy CMV-seropositive children can shed CMV for months at high, relatively stable levels. These data suggest that behavioral prevention messages need to address transmission via both saliva and urine, but also need to be informed by the potentially higher risks posed by saliva and by exposures to younger children.

Cohort study on maternal cytomegalovirus seroprevalence and prevalence and clinical manifestations of congenital infection in China

Abstract Congenital cytomegalovirus (CMV) infection is the leading viral cause of birth defects and developmental disabilities in developed countries. However, CMV seroprevalence and burden of congenital CMV infection are not well defined in China. Cohort of newborns from 5 birthing hospitals in 2 counties of Shandong Province, China, were enrolled from March 2011 to August 2013. Dried blood spots (DBS) and saliva were collected within 4 days after birth for IgG testing for maternal seroprevalence and real-time PCR testing for congenital CMV infection, respectively. Among 5020 newborns tested for CMV IgG, 4827 were seropositive, resulting in CMV maternal seroprevalence of 96.2% (95% confidence interval [CI]:95.6%–96.7%). Of the 10,933 newborns screened for congenital CMV infection, 75 had CMV detected, resulting in an overall prevalence of 0.7% (95% CI: 0.5%–0.9%), with prevalences of 0.4% (14/3995), 0.6% (66/10,857), and 0.7% (52/7761) for DBS, wet saliva, and dried saliva specimens screened, respectively. Prevalence of congenital CMV infection decreased with increasing maternal age (0.9%, 0.6%, and 0.3% among newborns delivered from mothers aged 16–25, 26–35, and >35 years, respectively; P = 0.03), and was higher among preterm infants than full term infants (1.3% vs 0.6%, P = 0.04), infants with intrauterine growth restriction (IUGR) than those without (1.8% vs 0.7%, P = 0.03), and twins or triplets than singleton pregnancies (2.8% vs 0.7%, P = 0.04). None of the 75 newborns exhibited symptomatic congenital CMV infection, and there was no difference in clinical characteristics and newborn hearing screening results between infants with and without congenital CMV infection at birth. Congenital CMV infection prevalence was lower and the clinical manifestations were milder in this relatively developed region of China compared to populations from other countries with similarly high maternal seroprevalence. Follow-up on children with congenital CMV infection will clarify the burden of disabilities from congenital CMV infection in China.

Quantitation of human herpesvirus 8 (HHV-8) antibody in patients transfused with HHV-8-seropositive blood.

BACKGROUND: Human herpesvirus 8 (HHV‐8) is endemic in Uganda where seroprevalence is approximately 40%. In a previous study, Ugandan patients receiving blood transfusions had multiple serum specimens collected for 6 months after transfusion to monitor for HHV‐8 infection. It was observed that several HHV‐8–seronegative patients were unexpectedly HHV‐8 seropositive after blood transfusion.

Urinary Cytomegalovirus Shedding in the United States: the National Health and Nutrition Examination Surveys, 1999–2004

Background There are no data on the prevalence of cytomegalovirus (CMV) shedding from a representative sample of the US population. This information is critical for understanding and preventing CMV. Methods We tested urine specimens from CMV immunoglobulin (Ig) G-positive participants aged 6-49 years in 3 racial/ethnic groups from the National Health and Nutrition Examination Surveys 1999-2004 for the presence of CMV DNA using real-time polymerase chain reaction assay. We examined the association of sociodemographic characteristics with shedding prevalence and viral loads. Results Among 6828 CMV IgG-positive participants tested, 537 had CMV DNA detected in urine-a shedding prevalence of 9.70%. Among persons aged 6-49 years, shedding prevalence was 3.83%. The prevalence of urinary shedding was inversely associated with increasing age (26.60%, 6.50%, and 3.45% in CMV IgG-positive participants aged 6-11, 12-19, and 20-49 years, respectively; P < .001 for trend test and pairwise comparisons). Urinary viral load also decreased significantly with age (mean, 2.97, 2.69, and 2.43 log10 copies/mL in those age groups, respectively; P < .001 for trend test and pairwise comparisons). Conclusions Urinary CMV shedding and viral loads decreased dramatically with age, likely reflecting higher rates of primary CMV infection and longer duration of shedding in younger individuals. The findings demonstrate that children aged 6-11 years continue to shed CMV at higher rates and viral loads than adolescents and adults and thus may still be an important source for CMV transmission.

Using theory-based messages to motivate U.S. pregnant women to prevent cytomegalovirus infection: results from formative research

BackgroundAn estimated 1 in 150 infants is born each year with congenital cytomegalovirus (CMV); nearly 1 in 750 suffers permanent disabilities. Congenital CMV is the result of a pregnant woman becoming infected with CMV. Educating pregnant women about CMV is currently the best approach to prevention. Limited research is available on how to effectively communicate with women about CMV. We conducted formative research on fear appeals theory-based messages about CMV and prevention with U.S. women. Fear appeal theories suggest that message recipients will take action if they feel fear.MethodsFirst, we conducted in-depth interviews (N = 32) with women who had young children who tested positive for CMV. Second, we conducted eight focus groups (N = 70) in two phases and two cities (Phase 2: Atlanta, GA; Phase 3: San Diego, CA) with pregnant women and non-pregnant women who had young children. Few participants knew about CMV before the focus groups.Participants reviewed and gave feedback on messages created around fear appeals theory-based communication concepts. The following concepts were tested in one or more of the three phases of research: CMV is severe, CMV is common, CMV is preventable, CMV preventive strategies are similar to other behavior changes women make during pregnancy, CMV preventive strategies can be incorporated in moderation to reduce exposure, and CMV is severe but preventable.ResultsParticipants recommended communicating that CMV is common by using prevalence ratios (e.g., 1 in 150) or comparing CMV to other well-known disabilities. To convey the severity of CMV, participants preferred stories about CMV along with prevention strategies. Participants also welcomed prevention strategies when it included a message about risk reduction. In general, participants said messages were motivating, even if they felt that it could be difficult to make certain behavior changes.ConclusionsFindings from this research can contribute to future efforts to educate pregnant women about CMV, especially regarding use of fear appeals-based messages. Pregnant women may face certain challenges to practicing prevention strategies but, overall, are motivated make changes to increase their chances of having a healthy baby.