Virus excretion and cell-mediated immunity during cytomegalovirus infection among healthy infants and children

Specific cell-mediated immunity (CMI) and virus isolation were examined longitudinally to clarify the mechanism of the cessation of virus excretion in inapparent cytomegalovirus (CMV) infection among healthy infants and children. We measured leukocyte procoagulant activity (LPCA) responses to CMV antigen and to a purified protein derivative of tuberculin (PPD), with results expressed as a percentage reduction of recalcification (RC) time. Based on the results in seropositive and seronegative adult control subjects, reductions in RC time of more than 10% were considered indicative of a positive LPCA response. The CMV-specific LPCA response was negative in all infants shedding the virus, despite the presence of circulating antibodies, but were converted from negative to positive when the virus excretion ceased. This suggests that cessation of the virus excretion in inapparent CMV infection among healthy infants and children probably results from the specific CMI.     

Salivary kallikrein excretion in hypertension

Summary According to immunohistochemical investigations kallikrein in the majors salivary glands is located predominantly at the apical border of the striated duct cells and as a luminal rim in the main excretory ducts. Comparatively the highest concentrations are observed in the submandibular gland of rats and cats in the cytoplasmic granules of the granular tubules.In normal humans and rats the kallikrein activity of parotid saliva is inversely related to flow rate and sodium concentration. An increased salivary kallikrein concentration is found in human essential hypertension and renoparenchymal hypertension associated with impaired kidney function. Furthermore in rats with various forms of hypertension (genetic hypertension, DOCTMA salt and renovascular hypertension) the salivary kallikrein secretion — as determined by the BAEE-esterase activity — is enhanced. In contrast to the kallikrein secretion the flow dependent sodium concentration of parotid saliva is reduced in human essential and renoparenchymal hypertension as well as in rats with various forms of experimental and genetic hypertension, which indicates an enhanced sodium reabsorption in the glandular duct system. Furthermore in most forms of hypertension, there is a tendency of higher potassium levels in the saliva.The pathogenesis of the enhanced glandular kallikrein secretion in hypertension is discussed with regard to a counterregulatory mechanism in hypertension as well as to a sympathicoadrenergic activation. The enhanced sodium reabsorption in the duct system in the various forms of hypertension could be the cause as well as a consequence of the enhanced kallikrein secretion.Supported by the Deutsche Forschungsgemeinschaft SFB 92, Biomund     

Cytomegalovirus infection and excretion in residents of a nursing home.

Cytomegalovirus (CMV), following primary infection, usually remains latent with the potential for reactivation and excretion in saliva and urine. The prevalence of CMV excretion has not been studied among the elderly. This study followed 54 nursing home residents (mean age 83 years and medically stable, but with a wide spectrum of medical conditions). Over a 6 month period these subjects were serially tested for viral excretion in saliva and urine and for CMV antibody. While approximately 93% of the residents tested were sero-positive, indicating previous CMV infection, there was no evidence of viral excretion in any resident during the study period. Therefore, it is unlikely that the elderly nursing home residents will prove to be a source of CMV to the health care workers or to their family members.     

Salivary antibody responses to oral and parenteral vaccines in children

Salivary IgA antibody to poliovirus and tetanus toxoid was measured in whole salivas of 151 children between 2 and 48 months of age from North America and from Scandinavia. Children from urban and suburban populations in the greater Boston, MA, area receive both oral poliovaccine and a parenteral injection with tetanus toxoid (TT), initially at approximately 2 months of age. Children from Göteborg, Sweden, initially receive parenteral injections of TT at 2 months of age and parenteral injections of killed polio vaccine initially at 9 to 10 months of age. Twenty-six percent of the Boston subjects who were less than 12 months old had detectable salivary IgA antibody to poliovirus after oral immunization. In contrast, within the first year after parenteral immunization with killed poliovirus, the Swedish group had detectable salivary antibody in 9% (1 of 13) of the subjects. Forty to 65% of the children in the older Boston-area age groups had positive salivary IgA antibody levels to this antigen. No differences were seen in salivary IgA antibody to TT among the three populations. By 36 months of age at least 50% of all populations had detectable salivary antibody to TT. The ratio of enzyme-linked immunosorbent assay (ELISA) activity using rabbit anti-human secretory component versus rabbit anti-human alpha chain was significantly higher in subjects less than 12 months of age compared with older groups. This suggested either that free secretory component was binding to tetanus toxoid or that secretory antibody of isotypes other than IgA was present in these youngest subjects.     

Prevalence and patterns of polyomavirus urinary excretion in immunocompetent adults and children

BK and JC polyomavirus infections are acquired commonly during childhood, mainly asymptomatically. These viruses are thought to remain latent in renal tissue after the primary infection and to reactivate under certain conditions. This reactivation leads to urinary excretion of virus particles, which can be detected by a range of methods. However, while this reactivation has been studied in depth in immunocompromised patients, little information is available about healthy individuals. The present study used PCR-based methods to examine urine samples from healthy individuals (51 adults and 15 children), and found that 62.7% of adults and 13.2% of children excreted polyomaviruses in the urine, mostly JC virus (41.2%). JC virus excretion was continuous, while BK virus excretion was mostly occasional.     

Detection of cytomegalovirus antigen and antibodies in the urine of small infants and children

The diagnostic efficacy of an enzyme immune assay to detect cytomegalovirus (CMV) antigen in the urine of infected infants and children was determined, and the effect that CMV-specific antibodies present in the urine have on the sensitivity of the test was ascertained. The antigen was detected in 84.4% of the CMV-culture-positive samples, while CMV-specific IgA was detected in 24% of CMV-culture-positive specimens. The absence of CMV-specific IgA correlated with detection of CMV antigen in the CMV-culture-positive urine specimens (p less than 0.05).     

Prospective study on maternal, intrauterine, and perinatal infections with cytomegalovirus in Japan during 1976-1990.

Since 1976, sera obtained serially from 10,218 pregnant women during the first, second, and third trimesters of gestation and cord sera were tested for CMV complement-fixing (CF) and immunofluorescent (IF) antibodies. CMV IgG-IF antibody was positive in 9,735/10,218 (95%) in the first trimester, and a significant rise of CF antibodies during pregnancy was found in 70/9,206 (0.76%) of the seropositive group and in 5/438 (1.14%) of the seronegative group. IgM antibody was found in 6/9,206 (0.06%) of seropositive women during the first trimester and in 7/70 (10.0%) of seropositive mothers with CF antibody rise and in 4/5 of seroconverted mothers of the seronegative group, suggesting that the incidence of primary infection with CMV during pregnancy was approximately 1% of susceptible women. All the mothers with immune response had infants with neither viruria nor IgM antibody in the cord blood, whereas seropositive mothers without an immune response had infants with viruria (7/1,826; 0.4%) or with IgM antibody in the cord blood (6/9,136; 0.06%). None of these 13 babies, shedding CMV or with IgM IF antibody, had physical or mental retardation. CMV IgG-IF antibody was present in almost 80% of infants between 7 and 12 months of age in 1988, suggesting that perinatal or postnatal CMV infection may occur in infants born to seropositive mothers in 70-80% of pregnancies.     

The cost-effectiveness of maternal and neonatal screening for congenital cytomegalovirus infection in Japan

Congenital cytomegalovirus infection is the most common congenital infection. Using a decision tree model, cost-effectiveness of maternal screening with subsequent prenatal valacyclovir treatment and newborn screening with neonatal valganciclovir treatment was evaluated. The incremental cost-effectiveness ratio (ICER) was calculated for (1) universal maternal antibody screening with prenatal valacyclovir treatment compared to targeted newborn screening, and (2) universal newborn screening with postnatal valganciclovir treatment compared to targeted newborn screening. We performed a one-way sensitivity analysis. Compared to targeted newborn screening, the ICERs for universal newborn screening and maternal screening were 2 966 296 Japanese Yen (JPY) (21 188 USD) and 1 026 984 JPY (7336 USD), respectively. In all scenarios in the one-way sensitivity analysis, the ICERs of the maternal screening and the universal newborn screening strategies were less than three gross domestic product per capita compared with the targeted newborn screening strategy. Both maternal and universal newborn screening strategies may be cost-effective than a targeted newborn screening program. The potential utility of the maternal screening with valacyclovir treatment strategy, while potentially cost effective in regions with lower baseline seroprevalence rates, requires further study as the modeling was based on limited evidence.     

巨细胞病毒感染与儿童免疫性血小板减少性紫癜的关系探讨

目的探讨人巨细胞病毒（HCMV）感染与儿童免疫性血小板减少性紫癜（ITP）的关系。方法采集154例ITP患儿（ITP组）和50例健康儿童（对照组）的血清样本,用Real-time PCR检测HCMV DNA,ELISA方法检测HCMV IgM、IgG抗体;其中105例ITP患儿和50例健康对照儿童采集了尿液标本,用Real-time PCR检测HCMV DNA,并比较ITP组HCMV DNA阳性患儿与阴性患儿的血小板数量的差异。结果 ITP患儿血清HCMV DNA、HCMV IgM及IgG抗体和尿HCMV DNA阳性率均明显高于健康对照儿童,两组比较差异均有统计学意义（P〈0.01）;ITP组HCMV DNA阳性患儿的血小板数量（29.72±14.54）×109/L与阴性患儿（41.28±18.35）×109/L比较差异有统计学意义（P〈0.05）。结论儿童感染HCMV可能是发生ITP的重要致病因素之一,这对指导临床有效治疗及预防ITP的发生有着积极的意义。     

Prevalence of antibodies to human cytomegalovirus in urban, kibbutz, and Bedouin children in southern Israel

Prevalence of antibody to human cytomegalovirus (CMV) was determined in a sample of 860 healthy children aged 1-13 years in Beer Sheva, in the Negev region of Israel. Three groups of children were tested: (1) urban Jewish children of low, middle, and high socioeconomic levels; (2) 8 rural communes (kibbutz) in which children live in close contact with each other from the 6th week of life under good hygienic conditions and a high standard of living; (3) Bedouin, seminomadic Arabs living in relatively poor hygienic conditions in the desert. Kibbutz children showed a significantly higher rate of CMV seropositivity by the second year of life than urban Jewish and Bedouin children (76% versus 44% and 54% respectively) with a gradual increase to 94% in the 10-13-year age group. Among children living in urban populations a significantly higher prevalence of CMV seropositivity was associated with crowding, but not with other socioeconomic indicators (place of residence, country of origin, or education level of parents). A marked rise of CMV seropositivity with age was found in urban Jewish children in the 2-5-year age group during which time they attend nurseries (44% to 67%) and in the Bedouin children in the 6-9-year age group (59% to 86%) when they first attend school. The data suggest that close contact is of major importance in CMV infection in childhood. The clinical implications of early acquisition and high prevalence of CMV antibodies in the kibbutz setting are discussed.     

儿童巨细胞病毒感染与甘露聚糖结合凝集素表达相关性研究

目的探讨甘露聚糖结合凝集素（MBL）基因多态性及血浆蛋白水平与儿童巨细胞病毒（HCMV）感染的相关性。方法收集2007年3～11月在浙江大学医学院附属儿童医院诊断为HCMV感染的患儿作为HCMV感染组,选择同期行健康体检的儿童作为对照组。对两组行MBL基因检测和分型,并对HCMV感染组进行随访,分别测定其急性期和恢复期血浆MBL蛋白水平。分别比较两组基因变异频率和血浆MBL蛋白水平。结果HCMV感染组纳入104例,对照组纳入105例;HCMV感染组有50例患儿进行随访,HCMV感染组MBL基因启动子区-550位点的L型变异频率明显高于对照组（56.7%vs34.3%,P=0.001）,野生单体基因型HYPA的频率明显低于对照组（47.6%vs62.8%,P=0.002）,完整基因型中高水平表达基因型（YA/YA）的频率低于对照组（41.3%vs60.0%,P=0.007）,而低水平表达基因型（YA/XA,YA/YB,XA/XA）的频率高于对照组（52.9%vs29.5%,P=0.001）。HCMV感染组急性期和恢复期血浆MBL蛋白水平均低于对照组（P=0.019和0.000）。HCMV感染组急性期血浆MBL蛋白水平高于恢复期（P=0.000）。结论MBL基因多态性导致的血浆MBL蛋白水平低下与儿童HCMV感染相关,提示MBL可能对儿童HCMV感染具有保护作用。     

Humoral immune responses and cytomegalovirus excretion in children with asymptomatic infection

Forty-two seropositive children aged 3 to 5 years attending a kindergarten were followed up for 1 year in order to examine the relationship between humoral immunity and cytomegalovirus (CMV) excretion status. Anti-CMV antibodies were measured at the beginning and end of the study by enzyme-linked immunosorbent assay, neutralizing antibody test, and immunoblot techniques. Among these children, 32 persistently shed virus in urine, 2 intermittently shed CMV, and 4 experienced reactivation during the study. Virus was never isolated from 4 seropositive children. The level of anti-CMV IgG antibody in seropositive children who remained nonshedders was significantly higher than in children who shed virus during follow-up. On immunoblots, all seropositive nonshedders reacted to a CMV-specific 65 kD antigen, whereas most shedders (80%) did not. These findings suggest that humoral immunity plays a role in controlling persistent CMV infection in children with asymptomatic infection. However, the humoral immunity measured by the neutralizing test and the presence of antibodies against CMV-specific envelope antigens (116 kD/55 kD) apparently play a limited role in modifying persistent excretion and regulating reactivation of latent CMV. Immune evasion by CMV to block these antigens may explain these results. © 1994 Wiley-Liss, Inc.     

Evaluation of antigen and antibody detection in urine specimens from children with congenital human cytomegalovirus infection

Fetal infection with human cytomegalovirus (HCMV) is the leading viral cause of brain dam age among newborns at birth or later in life. Efforts to screen newborns routinely for shedding of the virus by immunoassay have been ham pered by inhibitors in urine, reportedly the host protein beta2-microglobulin (β2m). An enzyme-linked immunosorbent assay (ELISA) was devel oped for the detection of HCMV antigen in which the reactivity was not affected by the presence of β2m, but nevertheless inhibition was observed when urine samples with high levels of virus were tested. The presence of antibodies to HCMV was demonstrated in these urine samples by antibody ELISA and immunoblot using the major antigenic protein of HCMV (pp150) expressed in Escherichia coli; this offers an alterna tive explanation for the inhibition in ELISA. The presence of HCMV antibodies correlated significantly with congenital HCMV infection (as detected by tissue culture isolation of virus from urine samples of newborns), especially with as ymptomatic cases (sensitivity 70%; specificity 94%). The data indicate a local (renal) immune response to HCMV in congenitally infected children, which may have future diagnostic applica tions. © 1995 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Salivary and serum IgA levels in a geriatric outpatient population

In two separate studies, specimens of saliva from 57 individuals over the age of 65 years (mean age, 76.7 years) and 37 persons under the age of 40 years (mean age, 28.8 years) were examined for concentrations of IgA as functions of volume, total protein, and electrolyte conductivity; some were also tested for IgG and IgM content. The results show that older persons have higher concentrations of these solutes in their saliva than do younger controls. This suggests that the ability to secrete IgA into saliva does not diminish significantly with aging.     

Cytomegalovirus infection in day care centers in Rome, Italy: viral excretion in children and occupational risk among workers

From nine day care centers in Rome, Italy, 253 children of middle to low socioeconomic classes were examined for cytomegalovirus (CMV) excretion in saliva. The overall excretion rate was 13%, with no marked differences between centers. Socioeconomic level, age of enrollment, chronological age, length of attendance, and number of siblings did not have any discernible influence on viral shedding. The most notable result is that during the second year of age, 100% of the excretors had been breast fed, but only 60% in the third year, indicating that maternal transmission is the most likely source of children's infection early in life. Serologic survey of 82 female workers in day care centers, 82 matched housewives, and 229 female students aged 14 to 18 years who were in training to care for children showed that at 14 years of age the CMV seropositivity rate is 85, which suggests that primary infection during childbearing age is an uncommon event in Rome.     

Viral load in children with congenital cytomegalovirus infection identified on newborn hearing screening

BackgroundCongenital cytomegalovirus (CMV) infection is the most common non-genetic cause of sensorineural hearing loss (SNHL) in children. However, congenital SNHL without other clinical abnormalities is rarely diagnosed as CMV-related in early infancy.ObjectivesThe aim of this study was to identify and treat patients with congenital CMV-related SNHL or CMV-related clinical abnormalities other than SNHL. The association between CMV load and SNHL was also evaluated.Study designNewborns who had abnormal hearing screening results or other clinical abnormalities were screened for congenital CMV infection by PCR of saliva or urine specimens, and identified infected patients were treated with valganciclovir (VGCV) for 6 weeks. The CMV load of patients with or without SNHL was compared at regular intervals during as well as after VGCV treatment.ResultsOf 127 infants with abnormal hearing screening results, and 31 infants with other clinical abnormalities, CMV infection was identified in 6 and 3 infants, respectively. After VGCV treatment, 1 case had improved hearing but the other 5 SNHL cases had little or no improvement. Among these 9 patients with or without SNHL at 1 year of age, there was no significant difference in CMV blood or urine load at diagnosis, but both were significantly higher in patients with SNHL during VGCV treatment.ConclusionsSelective CMV screening of newborns having an abnormal hearing screening result would be a reasonable strategy for identification of symptomatic congenital CMV infection. Prolonged detection of CMV in blood could be a risk factor for SNHL.     

Virus excretion and strain specific antibody responses after oral poliovaccine in previously immunised children

A nation-wide campaign with trivalent oral poliovirus vaccine was organized in Finland in February-March 1985 in order to stop the unexpected outbreak of poliomyelitis. Excretion time of the vaccine viruses and antibody responses due to vaccination were studied in a group of healthy 6-year-old children who were classmates to one of the patients during the outbreak and who also had been screened for excretion of the epidemic poliovirus type 3 strain. While faecal excretion of at least one of the three vaccine virus serotypes was documented in all 19 children, only one throat specimen out of 106 studied was positive in the virus isolation test. The mean excretion times for types 1, 2, and 3 were 13, 21, and 21 days, respectively, and five children were still excreting a vaccine virus strain at 5 wk. Faecal excretion of the type 3 vaccine virus was not seen in children who had been excreting the epidemic type 3 strain 4 mo earlier. Excretion of a respective vaccine virus strain was usually well correlated to a booster response in serum neutralising antibodies to types 2 and 3 but not to type 1 poliovirus. A relatively high prevaccination antibody level did not always prevent the take of the corresponding vaccine virus strain. An increase in the level of neutralising serum antibodies towards at least one poliovirus serotype was observed in all but one of the 17 children studied. Antibody responses to the live vaccine strains were similar to those towards the corresponding nonattenuated strains while the absolute antibody titres against the epidemic P3/Finland/23127/84 strain remained relatively low in most sera studied.(ABSTRACT TRUNCATED AT 250 WORDS)     

Patterns of divergence in the vCXCL and vGPCR gene clusters in primate cytomegalovirus genomes

Primate cytomegalovirus (CMV) genomes contain tandemly repeated gene clusters putatively encoding divergent CXC chemokine ligand-like proteins (vCXCLs) and G protein-coupled receptor-like proteins (vGPCRs). In human, chimpanzee and rhesus CMVs, respectively, the vCXCL cluster contains two, three and six genes, and the vGPCR cluster contains two, two and five genes. We report that (i) green monkey CMV strains fall into two groups, containing either eight and five genes or seven and six genes in the respective clusters, and (ii) owl monkey CMV has two and zero genes. Phylogenetic analysis suggested that the vCXCL cluster evolved from a CXCL chemokine gene (probably GRO-α) that was captured in an incompletely spliced form by an ancestor of Old and New World primate CMVs, and that the vGPCR cluster evolved from a GPCR gene captured by an Old World primate CMV. Both clusters appear to have evolved via complex duplication and deletion events.     

Correlation between sodium and potassium excretion in 24- and 12-h urine samples

Low-sodium and high-potassium diets have been recommended as an adjunct to prevention and treatment of hypertension. Analysis of these nutrients in 24-h urine has been considered the reference method to estimate daily intake of these minerals. However, 24-h urine collection is difficult in epidemiological studies, since urine must be collected and stored in job environments. Therefore, strategies for shorter durations of urine collection at home have been proposed. We have previously reported that collecting urine during a 12-h period (overnight) is more feasible and that creatinine clearance correlated strongly with that detected in 24-h samples. In the present study, we collected urine for 24 h divided into two 12-h periods (from 7:00 am to 7:00 pm and from 7:00 pm to 7:00 am next day). A sample of 109 apparently healthy volunteers aged 30 to 74 years of both genders working in a University institution was investigated. Subjects with previous myocardial infarction, stroke, renal insufficiency, and pregnant women were not included. Significant (P < 0.001) Spearman correlation coefficients (r_s) were found between the total amount of sodium and potassium excreted in the urine collected at night and in the 24-h period (r_s = 0.76 and 0.74, respectively). Additionally, the 12-h sodium and potassium excretions (means ± SD, 95% confidence interval) corresponded to 47.3 ± 11.2%, 95%CI = 45.3-49.3, and 39.3 ± 4.6%, 95%CI = 37.3-41.3, respectively, of the 24-h excretion of these ions. Therefore, these findings support the assumption that 12-h urine collected at night can be used as a reliable tool to estimate 24-h intake/excretion of sodium and potassium.