Scanning electron microscopic appearance of viral-antigen-coated polystyrene balls.

A radioimmunoassay (RIA) was recently developed for the detection of antiviral IgG and IgM class-specific antibodies using antigen-coated polystyrene balls as the RIA solid-phase. In this communication the attachment and distribution of herpes simplex virus (HSV) capsid and envelope antigens and rubella viruses on the surface of the balls was examined by scanning electron microscopy (SEM). In SEM the surface of the untreated 'clear frosted' polystyrene balls appeared very uneven with innumerable pits and grooves. The viral particles were haphazardly distributed both in the grooves and on the exposed surface of the balls. The strength of adsorption of the viral antigens onto the balls seemed to be remarkably resistant to outside mechanical forces. HSV antigens frequently appeared in clusters, whereas rubella viruses were mostly found as single particles.

IgM-class rheumatoid factor interference in the solid-phase radioimmunoassay of rubella-specific IgM antibodies.

The interference of IgM-class rheumatoid factor (RF) in the solid-phase radioimmunoassay (RIA) of rubella virus IgM antibodies was studied. Acute rubella infections did not significantly activate RF. False-positive rubella antibody results were obtained, however, when patients with raised RF levels were tested. If a low rubella IgG antibody titre was present, a high level of RF was required to cause a false-positive IgM result; conversely, in sera with high IgG titres, only a low level of RF was required for interference. Although the false-positive IgM titres obtained were generally low, thet did show a positive correlation to both RF levels and rubella IgG titres. False-positive results were successfully avoided by removing the RF by absorption with heat-aggregated human gamma globulin. The absorption procedure did not affect true rubella IgM antibody titres.

Avidity of IgG antibodies against mumps, parainfluenza 2 and Newcastle disease viruses after mumps infection.

Paired serum samples from 39 patients with recent mumps infection were assayed for IgG antibodies against mumps, parainfluenza 2 and Newcastle disease virus (NDV). A modified enzyme immunoassay was used, giving separate estimates of high avidity antibodies (EHAA) and total specific antibodies (ETSA). A marked cross-reaction was seen between mumps and parainfluenza 2 virus, with changes of ETSA between paired samples of about the same magnitude against both these viruses. The mean change of EHAA against mumps was, however, significantly greater than that against parainfluenza 2. There were 16 patients who had a change of ETSA greater against parainfluenza 2 than against mumps. When the EHAA responses were compared, there were only 8 such patients. The responses against NDV were negligible. Estimation of antibody avidity, even by the arbitrary method used, can distinguish between homotypic and cross-reactive heterotypic antibodies after mumps infection. The implications for expressing the results of enzyme immunoassay are discussed.

An ELISA for the estimation of high-avidity and total specific IgG and IgM antibodies to rubella virus.

High-avidity and total specific IgG and IgM antibodies to rubella virus were measured by using a curve-fitting analysis for the dose-response curves of enzyme-linked immunosorbent assay (ELISA). The analysis of follow-up samples from 14 patients with primary rubella infection revealed that these two antibody categories had different kinetics during the time after rash. The high-avidity IgG antibodies increased more slowly than total specific IgG antibodies. In the IgM response, high-avidity antibodies reached their maximum slightly earlier than total specific antibodies. After reinfection with rubella, 14-30 days after the illness, convalescent patients had higher amounts of high-avidity IgG antibodies when compared to the patients who suffered from primary rubella infection. These findings are in agreement with the results obtained by measuring antibody affinity in experimental animals after immunization.

Solid-phase enzyme-immunoassay for the detection of herpes simplex virus antigens in clinical specimens.

An indirect solid-phase enzyme-immunoassay (EIA) for the detection of herpes simplex virus (HSV) antigens in clinical specimens was developed. Rabbits and guinea pigs were hyperimmunized with highly purified nucleocapsids of HSV type 1. Microtitre plates were coated with 0.25 microgram of guinea pig anti-herpes simplex type 1 immunoglobulins per well. Clinical specimens, diluted in phosphate buffered saline containing fetal calf serum and detergents, were sonicated and incubated in the test wells overnight at 37 degrees C. Rabbit anti-HSV immunoglobulins were added as a secondary antibody at a concentration of 3.2 micrograms per well, and peroxidase conjugated swine antibodies against rabbit immunoglobulins, diluted 1:1,000, were used as a fourth layer. Clinical specimens which were sent for virus isolation or for isolation of Chlamydia trachomatis were tested by the developed assay and 20 out of 27 isolation positive specimens were found positive by EIA. Five out of 67 specimens negative by isolation gave positive results by EIA. The specificity of the results was confirmed by a control test using wells coated with normal guinea pig immunoglobulins. The test detected antigens from both serotypes of HSV. Cross reactions with varicella-zoster- or with cytomegalovirus were not found, and antigens from uninfected cells did not result in false positive results.

Local IgA-class antibodies against respiratory viruses in middle ear and nasopharyngeal secretions of children with secretory otitis media.

The presence of antibodies against some important respiratory viruses in the middle ear and nasopharyngeal secretions of 52 children with secretory otitis media (SOM) was investigated in order to find out about the role of these viruses in the development of SOM. The method employed was a sensitive radioimmunoassay test. Antibodies to adeno, syncytial, and parainfluenza 3 viruses were detected in about 50%, 50% and 20% of the patients, respectively. In eight patients the middle ear secretion/nasopharyngeal secretion titer ratio of antibodies to one virus was selectively increased in comparison with the other viruses tested, indicating an active local production of specific antibodies in the middle ear. Further studies are required to determine the cause of such an active antibody synthesis and its possible role in the etiopathogenesis of SOM.

A new method for the identification of cerebrospinal fluid leakage.

Apart from the use of anamnestic data the most common techniques for the diagnosis of CSF leakage have included X-ray studies, and chemical analysis of glucose, protein, and electrolytes of the fluid obtained from the nose or ear, intrathecal staining, and radioactive cisternography. These studies, although useful, have not always succeeded in demonstrating the CSF leakage, especially when the leak is delayed, small, or contaminated. A new immunochemical technique for the identification of the CSF leakage is described. It is based on demonstration of an extra band of transferrin located in the beta 2-fraction of protein electrophoresis of CSF. This beta 2-transferrin is pathognomonic for liquor and could not be demonstrated in serum, nasal secretions, saliva, tears, or peri- and endolymph. After routine protein electrophoresis on cellulose acetate membranes, the transferrins are identified by application of anti-transferrin on beta-regions. Stained precipitates in both beta-regions demonstrate clearly the presence of CSF. Compared with other methods, the new technique offers many advantages. The amount of sample needed for the procedure is small, moderate contamination does not invalidate it, it makes it possible to localize the leak by differential suction, and it is absolutely safe for the patient.

Prevalence of secretory otitis media in seven to eight year old school children.

One thousand two hundred and seven school children aged seven to eight years were examined in the spring of 1978 in order to determine the frequence of undiagnosed secretory otitis media (SOM). All children were without any subjective ear symptoms. Two and eight tenths percent of the children were found to have SOM. The relation between SOM and the appearance of allergy, the occurrence of earlier otitis media, the occurrence of repeated upper respiratory tract infections and the treatment of earlier middle ear infections are discussed.

[Otosclerosis in children (author's transl.)]. / Otosklerose im Kindesalter

11 children (13 ears) have been operated upon for otosclerosis. In ten cases the stapes footplate was found totally fixed, with histological verification of the diagnosis of otosclerosis. Conservative surgery of the oval window was possible in only four cases. All other patients required total removal of staples or footplate. Findings indicate that clinical otosclerosis occurring in childhood results in an otosclerotic process in the oval window region with total fixation of the footplate. Thus, correction usually requires removal of at least the entire footplate.

Persistence of immunoglobulin G and immunoglobulin M antibodies after postnatal rubella infection determined by solid-phase radioimmunoassay.

The appearance and persistence of immunoglobulin M (IgM) and IgG antibodies in postnatal rubella infections were studied by employing a solid-phase radioimmunoassay test. Altogether, 222 serial serum specimens from 51 patients with acute rubella infection were tested. Both IgG and IgM antibodies developed rapidly and appeared in all patients within 4 days after the onset of rash. In some patients, the IgM antibodies clearly preceded the IgG antibodies; however, the reverse situation was also noticed in a few cases. The IgG antibodies showed only minor changes after 8 to 10 days from the onset of rash. The IgM titers also reached a maximum level at approximately 8 to 10 days after the onset of rash, after which time a rapid decrease was normally seen. The mean half-life of IgM antibodies after 15 days from the onset of rash was 4.5 days, giving for IgM antibodies persistence times from 43 to approximately 80 days. Two patients with a prolonged IgM antibody response were detected. One of these patients had bilateral arthritis of the knee as a complication, whereas in the other patient no complication caused by rubella virus was detected. The IgM antibody response and its value in diagnosis are discussed.

Antibody responses in patients with rubella infection determined by passive hemagglutination, hemagglutination inhibition, complement fixation, and solid-phase radioimmunoassay tests.

Antibody responses in serial serum specimens collected from 31 patients with an acute rubella infection were determined by passive hemagglutination (PHA), hemagglutination inhibition (HI), complement fixation (CF), radioimmunoassay (RIA) immunoglobulin G (IgG), and RIA immunoglobulin M (IgM) tests to evaluate the effectiveness of these tests in diagnosing a recent infection. The HI, RIA IgG, and RIA IgM antibodies appeared almost simultaneously and reached the maximum level about 1 week after the onset of rash. Compared to these, the CF antibodies developed only slightly later, whereas the development of the PHA antibodies was much more delayed. The RIA IgM response was shown to be transient, lasting approximately 1.5 to 2.5 months postinfection. The results of this study indicate that demonstration of specific IgM antibodies is the best method for diagnosing a recent infection, one within 2 months after the onset of the illness. If an IgM test is not available, a combination of the HI and PHA tests is recommended.

Solid-phase radioimmunoassay of IgA, IgG, and IgM antibodies to human rotavirus.

A solid-phase radioimmunoassay (RIA) has been developed for the detection of human rotavirus-specific IgA, IgG, and IgM antibodies. Nebraska calf diarrhea virus grown in LLC-MK2 cell cultures in the presence of trypsin was directly adsorbed onto polystyrene balls, and antibodies that attached to the virus-coated balls were detected by subsequent binding of 125I-labeled antibodies specific to human alpha, gamma or mu chains of human Iga, IgG, or IgM immunoglobulins. A total of 116 serum specimens from 58 adult patients were tested. Binding ratios between the positive and the negative serum varied between 5 and 15, occasionally being 20 or more in the IgA and IgG assays, but rarely exceeding 3 in the IgM assay. The RIA was found to be more sensitive in detecting antibodies to rotavirus than the complement fixation (CF) test, the RIA titers obtained being 50--100 times as high as the CF titers. The method described offers a possibility of evaluating the immune response to human rotavirus and of detecting recent infection.

[Ultrasound testing in the diagnosis and management of maxillary sinusitis in children (author's transl)]. / Die Verlaufskontrolle des Heilungsprozesses der kindlichen Kieferhöhlenentzündung mit der Ultraschalldiagnostik.

A- and B-mode ultrasound testing was used in conjunction with X-ray studies as screening tests for the detection of maxillary sinusitis in 280 children (aged 4-10 years) about to undergo adenoidectomy, and/or tonsillectomy and/or tympanostomy. X-rays were abnormal in 114 (41%) children, while sinus disease with the retention of discharge was diagnosed by ultrasound in 63 (23%) children. These latter children were then treated for ten days with amoxicillin and decongestant (Rinexin). At time of initial surgery, 63 maxillary sinuses (in 43 of the children) were punctured and irrigated. Another group (consisting of 27 sinuses in 20 children) was treated without antral puncture. All children were reexamined after 10, 20 and 30 days with ultrasound and radiography. After 10 days, there was no discharge found in 86% of the sinuses treated by antral puncture and in 85% of the control sinuses. After one month, all sinuses which had been irrigated were found to be free of disease, while three (11%) of the control group contained discharge. However, the healing process in all patients seemed to be slower, as evidenced by sequential sinus X-rays.--We believe that ultrasonic evaluation of the maxillary sinuses is a simple, rapid and reliable method for the diagnosis and followup of maxillary sinusitis in children. With this technique, it is possible to follow the disappearance of residual sinus discharge as well as diagnose cases which need active treatment.

Persistent rubella-specific IgM-antibody in the cerebrospinal fluid of a child with congenital rubella.

Rubella-specific IgM-antibody was detected, using a solid-phase radioimmunoassay (RIA) method, in the CSF of a child with congenital rubella at ages 3 and 4 years. No rubella-specific Igm was found in the CSF of 20 other children with congenital rubella, and the ratios of rubella-specific IgG RIA antibody titres in serum and CSF were normal.

Hemagglutination by BK virus, a tentative new member of the papovavirus group.

Some characteristics of hemagglutination (HA) by the BK virus, a new candidate for the papovavirus group, have been studied. Hemagglutinin prepared from cell cultures was found to be partially masked by inhibitors which could be dissociated from the virus by incubation at 37 C or by fluorocarbon extraction. Optimal conditions for HA are outlined. In routine tests, 0.5% human erythrocytes were used. The reaction was carried out at pH 7.0 on ice-water slurry. BK hemagglutinin receptors on human erythrocytes were found to be more resistant to neuraminidase than polyoma receptors. By gradient centrifugation analysis, two types of particles were found to be responsible for HA: (i) full, deoxyribonucleic acid-containing particles with a density of 1.325 g/cm(3) and (ii) empty capsids with a density 1.29 g/cm(3). Based on particle counting, one HA unit was calculated to correspond to 3 x 10(6) virus particles.