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Biomedical subjects

S Stagno

Publications and source records attributed to S Stagno.

At least 109 records · Page 6Linked to original sources
PubMed1978

A search for antigen-antibody complexes in pre-eclampsia: further evidence against immunologic pathogenesis.

Circulating immune (antigen-antibody) complexes have been proposed as possible important in the pathogenesis of pre-eclampsia. Thirty-four serum samples from pre-eclamptic women were examined for the presence of antigen-antibody complexes by the C1q binding and Raji cell assays. Slightly abnormal C1q binding occurred in two serum samples, while all Raji cell determinations were found to be in the normal range for a healthy, nonpregnant population. It is concluded that circulating immune complexes do not occur regularly in pre-eclampsia.

Antigen-Antibody Complex↗
PubMed1978

A longitudinal study of the serological and virological status of 18 women infected with cytomegalovirus.

18 women, of known seropositivity, have been followed for between 18 and 66 months (mean 50.2 months) for viral excretion and serological changes. CMV was isolated from 58/146 (39.7 per cent) cultures from various sites, mostly cervix. A total of 129 sera were obtained and each was titrated in the late antigen, early antigen and anti-complement immunofluorescence assays, as well as the complement fixation and microneutralisation tests. From 3 women virus was consistently re-isolated, from 3 others virus was never re-isolated and the remaining 12 women excreted virus intermittently during the period of study. No significant changes in antibody titres could be detected by any of the 5 serological assays in any woman during periods of viral excretion. This suggests that local reactivation of latent CMV infection is not associated with a demonstrable systemic antibody response. Inter-assay correlations were sought for each of the 10 possible combinations of pairs of tests. Significant correlations were found for most pairs of tests, with the notable exception fo those involving the early antigen test. This confirms that antibodies detected in this assay are distinct from those detected by the other 4 serological assays.

Adult↗
PubMed1978

Antibody response to live virus vaccines in congenital and neonatal cytomegalovirus infections.

When 42 infants with congenitally or neonatally acquired cytomegalovirus infections were one year of age, they were given live attenuated measles-mumps-rubella combined vaccine to determine what effect, if any, the existence of chronic CMV infection has on the antibody response to measles and rubella antigens. When the infected infants were compared with 60 healthy non-CMV-infected control infants, no significant difference in the seroconversion rates or ultimate antibody levels was observed with either measles or rubella antigens. Persistence of antibody, when measured three years after vaccination, was likewise similar in each group; levels had waned only slightly. These results demonstrate the intactness of humoral immunity in children with pre- and perinatal CMV infection.

Antibodies, Viral↗
PubMed1978

Perinatal cytomegalovirus infection: influence of placentally transferred maternal antibody.

The kinetics of the response to passively transferred maternal neutralizing antibody were studied for determination of whether this antibody offered protection against primary cytomegalovirus (CMV) infection in the offspring. Antibody response was determined in 17 infants infected in the immediate perinatal period and in 18 appropriate control subjects. Levels of neutralizing antibody in serum obtained at birth and at one month of age were similar in infected and in exposed, uninfected neonates. In addition, the quantity of neutralizing antibody did not influence the time of onset of viruria. Clearly, passive humoral immunity failed to prevent naturally acquired primary CMV infection in a significant number of young infants exposed to virus during and shortly after delivery.

Antibodies, Viral↗
PubMed1978

Use of isolated nuclei in the indirect fluorescent-antibody test for human cytomegalovirus infection: comparison with microneutralization, anticomplement, and conventional indirect fluorescent-antibody assays.

Use of an antigen consisting of purified isolated nuclei from a mixture of human cytomegalovirus-infected and uninfected fibroblasts in a 2:1 ratio is a simple and reliable method for eliminating nonspecific fluorescence associated with the presence of Fc-immunoglobulin G receptors in the cytoplasm of infected cells. The specificity obtained with this antigen on 100 normal human sera was 99, 100, and 98% when compared with microneutralization, anticomplement immunofluorescence, and conventional indirect fluorescent-antibody assays, respectively. Also, 95% of the antibody titers obtained with the nuclear antigen had a perfect correlation with or were within a fourfold-dilution difference of the antibody levels obtained by anticomplement immunofluorescence and the conventional indirect fluorescent-antibody test.

Antibodies, Viral↗
PubMed1978

Pneumocystis carinii infection: evidence for high prevalence in normal and immunosuppressed children.

Using Pneumocystis carinii organisms propagated through three passages in embryonic chick epithelial lung cultures, specific antigens and antisera were prepared for use in counterimmunoelectrophoresis and indirect immunofluorescent antibody techniques. These methods proved to be specific and sensitive for the detection of P. carinii antigen and antibody, respectively, in sera, and were applied to the study of cancer patients with P. carinii pneumonitis (PCP), cancer patients without pneumonitis, and normal children. Antigenemia was detected in 95% of patients with PCP, in 15% of cancer patients without pneumonitis, and in none of the normal children tested. In cross-sectional and longitudinal studies of normal infants and children, acquisition of serum antibody to P. carinii was demonstrated to occur progressively with increase in age. By 4 years of age two thirds of the normal children were found to have antibody to P. carinii in titers of 1:16 or greater. These studies indicate that subclinical P. carinii infection is highly prevalent in normal children, analogous to other opportunistic infections where active disease is manifest predominantly in the compromised host.

Antigens, Protozoan↗
PubMed1977

Congenital cytomegalovirus infection.

The overall prevalence of congenital cytomegalovirus infection among the offspring of a highly immune young female population was 2.4 per cent (23 of 939). To ascertain whether the presence of anticytomegalovirus antibodies protects the developing fetus, we examined the offspring of 239 prospectively studied women. Despite substantial levels of preconceptional antibodies, intrauterine cytomegalovirus infection occured in seven of 208 (3.4 per cent) seroimmune women. Three neonates with congenital infection were born to 31 initially seronegative women. All the congenitally infected infants had subclinical involvement. Maternal humoral immunity may not protect the fetus against congenital cytomegalovirus infection. Neutralization kinetics and restriction enzyme analysis with endonucleases (EcoR-1 and HinD 111) demonstrated antigenic and genetic homology between viral strains isolated from two siblings consecutively infected in utero, indicating that repeat maternal infection with the same virus is transmissible to sequential products of conception.

Adolescent↗
PubMed1977

Specific impairment of cell-mediated immunity in mothers of infants with congenital infection due to cytomegalovirus.

Specific lymphocyte-mediated cytotoxicity to cytomegalovirus (CMV) in eight infants (six to 27 months old) with congenital CMV infection and in the mothers of six of these infants was evaluated with use of a 51chromium (51Cr)-release microassay. The control population consisted of 25 normal newborns, children, and adults. The titers of indirect hemagglutinating (IHA) antibody to CMV in the infected infants ranged from 1:16 to 1:1,024. All of these infants had detectable specific immune release of 51Cr that ranged from 3.3% to 48.9% (mean +/-SE, 21.0%+/-5.6%). The mothers of these infants demonstrated significantly elevated titers of IHA antibody to CMV (geometric mean titer, 1:410) as compared with a mean titer of 1:22 in controls (t = 5.71; P less than 0.001) but showed significantly depressed specific immune release (9.2% +/- 3.2%) compared with that of normal seropositive controls (24.8% +/- 2.8%; t = 3.31; P less than 0.001). In addition, two adult nulliparous women with persistent CMV viruria were also found to have depressed specific immune release to CMV (10.8% and 16.2%). These data suggest that a specific impairment in cell-mediated immunity to CMV occurs in mothers of infants with congenital CMV infection and in some persons who persistently excrete CMV.

Adult↗
PubMed1977

Immune complexes in congenital and natal cytomegalovirus infections of man.

The occurrence of circulating immune complexes was investigated in 31 patients with cytomegalovirus infection (29 infected in utero and 2 with natal infection) and 34 uninfected controls. Anti-complementary activity above 1:20 occurred in 34% (29/86) of the sera tested from the infected group in contrast to 7.5% (3/40) in the controls (P < 0.005). When assayed by means of a lymphoblastoid cell line (Raji cell test), the reactivity in these groups was 45 (39/86) and 2.7% (1/36), respectively (P < 0.001). Correlation of results between these two complement-dependent assays occurred in 75% of samples collected from the infected group. Frequency of reactivity was higher in severe intrauterine infection and during the 1st yr of life paralleling the patterns of viral excretion and humoral immune responses. Physicochemical characterization demonstrated that reactive substances in sera were acid-dissociable and, in one sample tested, contained 7S IgG antibodies with cytomegalovirus (CMV) specificity. Circulating immune complexes were heavier (18-22S) in sick, as opposed to subclinically CMV-infected patients, in whom intermediate size complexes (12-16S) were found. In three of four symptomatic patients whose demise was due to severe congenital infection, granular deposits of immunoglobulins and C3 were detected in a pattern typical of immune complexes along the glomerular basal membrane of the glomeruli. Whether or not circulation and deposition of heavier immune complexes contributed to the adverse clinical outcome is unresolved. Because of the high incidence of both congenital and natal CMV infections, definition of the pathogenetic potentials of both heavy and intermediate size immune complexes is required to design more effective therapeutic measures.

Antibodies, Viral↗
PubMed1977

Auditory and visual defects resulting from symptomatic and subclinical congenital cytomegaloviral and toxoplasma infections.

Sensorineural hearing loss was present in ten of 59 (17%) patients with congenital cytomegalovirus (CMV) infection (three of eight born with symptomatic and seven of 51 born with subclinical infection). The defect was bilateral in eight, moderate to profound in eight, and of progressive nature in two. Hearing loss did not occur in 21 patients with natal CMV infection nor in seven of 12 patients with congenital toxoplasmosis. Histopathologic and immunofluorescent studies of the inner ear in two of three neonates who died with severe infection revealed that viral antigens were widely distributed in cochlear structures. Eye pathology was associated only with congenital Toxoplasma (nine of 12) and CMV (seven of 43) infections. Visual impairments were more prominent and severe in those born with symptomatic infections, exclusively so with CMV. However, ocular defects, in particular chorioretinitis, developed after birth in five of eight patients born with asymptomatic congenital toxoplasmosis. These data firmly establish clinically inapparent congenital CMV infection as a major public health problem and confirm the fact that congenital toxoplasmosis may be associated with late-appearing, debilitating chorioretinitis.

Audiometry↗
PubMed1976

Protracted pneumonitis in young infants associated with perinatally acquired cytomegaloviral infection.

Two infants developed a protracted pneumonitis with lower respiratory obstruction beginning at one month of age. Lung biopsy in one suggested a viral etiology which prompted an extensive investigation of each infant for specific etiology. Virologic, serologic, immunologic, and electronmicroscopic studies indicated that cytomegalovirus was a major causative factor. The infections were apparently acquired at birth from infected maternal genital tracts and have persisted for prolonged periods of time. Evidence for gross immunologic defect as a precipitating cause was lacking. These infants serve to emphasize the possible pathologic potential of CMV when acquired in early life even in the absence of iatrogenic immunosuppression.

B-Lymphocytes↗
PubMed1975

Cervical cytomegalovirus excretion in pregnant and nonpregnant women: suppression in early gestation.

Comparison of 659 pregnant and 202 nonpregnant women with similar demographic characteristics showed overall rates of cervical cytomegalovirus excretion that were identical (9.5% vs. 9.4%) and were surprisingly high, especially since 89% of the pregnant group possessed antibody to cytomegalovirus when admitted to the study. Prevalence of cytomegalovirus among gravidas was significantly lower during the first (1.6%) than during the third (11.3%) trimester. Thus, early pregnancy appeared to exert a suppressive effect on viral excretion that waned with advancing gestation. A similar but less significant occurrence was observed in the two groups with respect to viuria. Increasing age also appeared to suppress the virologic expression of cervical and urinary tract infection, whereas multiparity seemingly produced such an effect only in the cervix. Among both cervical and urinary excreters, a few shed virus thoughout pregnancy, and others shed virus intermittently; however, viral shedding most commonly began in late gestation and frequently continued into the postpartum period. Primary infection was not documented, and antibody status remained unchanged with the advent of viral excretion in most cases. Thus, reactivation of endogenous virus seems the most likely explanation for viral shedding in our population. Similar rates of isolation of Neisseria gonorrhoeae in excreters and nonexcreters further argue against the other major possibility, venereal reinfection.

Amniotic Fluid↗
PubMed1975

Comparative serial virologic and serologic studies of symptomatic and subclinical congenitally and natally acquired cytomegalovirus infections.

Infants with congenitally (38) and natally (17) acquired cytomegalovirus infection were prospectively studied by means of virologic and multiple serologic assays. These infections were characterized by chronic viral excretion (measured in years). The quantity of virus excreted in the urine during early infancy was significantly greater in infants who acquired infection in utero, particularly amon those born with overt disease; thereafter, all three groups (congenital symptomatic, congenital asymptomatic, and natal) excreted similar amounts of virus. The patterns of antibody responses, particularly the fluorescent antibody response to the early antigen and the complement-fixing antibody response, further indicated that congenitally infected infants (especially symptomatic ones) bear a greater antigenic burden than do natally infected infants. From a diagnostic standpoint, the test for fluorescent antibody to the late antigen was the most sensitive assay, whereas the test for complement-fixing antibody proved to be the least useful, The indirect hemagglutination assay, although performed only in infants with natal infection, was only slightly less sensitive than the fluorescent antibody procedure; by the former technique, diagnostic rises were detected in all but one infant after the onset of viruria.

Antibodies↗