Biomedical subjects

M Zerbini

Publications and source records attributed to M Zerbini.

At least 91 records · Page 5Linked to original sources

PubMed1989

An amplified dot immunoassay for the direct quantitation of adapted and wild strains of human cytomegalovirus.

A rapid and simple quantitative dot immunoassay for a cell-adapted reference strain of cytomegalovirus (CMV) and for wild strains of CMV present in clinical urine samples was developed. The assay was performed on nitrocellulose paper dotted with several dilutions of viral pellets free of cellular debris. Viral dilutions were treated with a monoclonal antibody to the major component of the viral capsid. To amplify the reaction, a three-dimensional complex of streptavidin and biotinylated horseradish peroxidase was used as the detector system. The dot immunoassay, which does not require cell cultures, yielded results within one day. A significant correlation was found between CMV titers obtained by dot immunoassay and CMV infectious units determined by immunoalkaline phosphatase staining of CMV-late antigen positive cells.

Antibodies, Monoclonal↗

PubMed1988

Rapid quantitative assay of cytomegalovirus infectivity.

A rapid quantitative assay was developed to determine cytomegalovirus infectious units. The assay yielded results in three days. The rapid quantitation of cytomegalovirus infectivity was developed by evaluating the number of cells that expressed cytomegalovirus-late antigens at the end of a single replication cycle (62 h post-infection). Late antigens were visualized by immunoalkaline phosphatase staining using a monoclonal antibody against the major viral capsid protein (66.8 kDa). Thirty-five cytomegalovirus samples were examined. The values of the infectious units obtained by immunoalkaline phosphatase staining were correlated significantly with the values determined by the classical plaque-forming technique.

Antigens, Viral↗

PubMed1988

Immunocytochemical detection of antibodies to Epstein-Barr virus nuclear antigen by a streptavidin-biotin-complex assay.

An immunocytochemical staining for the detection of antibody to Epstein-Barr virus nuclear antigen in cell smears was developed by using a three-dimensional complex of streptavidin and biotin labeled with horseradish peroxidase as the detector system. The presence of antibody against Epstein-Barr virus nuclear antigen was revealed by a dark staining of the nuclei of Raji cells. A significant correlation was found between the titers obtained with our assay and titers obtained by anticomplement immunofluorescence on 110 serum samples. Our assay did not require an Epstein-Barr virus-negative serum source for fresh complement and gave a permanent record of the reaction that could easily be observed under an ordinary light microscope.

Antibodies, Viral↗

PubMed1988

Impairment of cytomegalovirus and host balance in elderly subjects.

The titres of IgG antibody against "late antigens", "immediate early antigens", and "early antigens" induced by cytomegalovirus (CMV) and IgM antibody against "late antigens" induced by CMV were analysed in 67 geriatric subjects by immunocytochemical techniques. The titres obtained were compared with those of an adult control population. Significantly increased titres of IgG antibody against induced antigens and a significant increase in CMV reactivated infections occurred in the elderly compared with control subjects. These findings indicate that the CMV and host balance in the elderly is disturbed, leading to activation of the CMV latent carrier state that follows primary CMV infection.

Aged↗

PubMed1988

Expression of cytoskeleton components in various Epstein-Barr virus infected cell lines.

It has been shown that viruses can induce alterations in the content and distribution of cytoskeleton structures, particularly actin microfilaments and microtubules. An immunomorphologic study of the cytoskeleton components of various EBV-infected cell lines with expression of different functions of EBV genome has been performed using antibodies to each of its three major components. Intermediate filaments and microtubules were similarly represented in all examined lymphoblastoid cell lines. The distribution of actin microfilaments, on the contrary, differed significantly from cell line to cell line. It is concluded that the morphologic expression of actin might depend on the expression of EBV genome. Furthermore, some of these cell lines might represent a useful substrate for the identification of anticytoskeleton antibodies, mainly anti-actin antibodies, in human sera.

Actins↗

PubMed1987

Dot immunoperoxidase assay using monoclonal antibody for direct detection of cytomegalovirus in urine samples.

A rapid, simple dot immunoperoxidase assay for the direct detection of cytomegalovirus in clinical urine samples was developed. The assay was performed on nitrocellulose paper dotted with urine pellets free of cellular debris. Cytomegalovirus was detected with a monoclonal antibody to the capsid antigen, and the complex was visualized by immunoperoxidase staining. Positive reactions appeared as well-defined dark blue spots. Of the 87 urine samples examined, 10 proved positive in the dot immunoperoxidase assay, and 77 proved negative. The results agreed completely with the detection of cytomegalovirus-induced antigens in cell cultures inoculated with clinical specimens.

Antibodies, Monoclonal↗

PubMed1987

Comparison of the immune response to Epstein-Barr virus and cytomegalovirus in sera and synovial fluids of patients with rheumatoid arthritis.

The immune response against two herpesviruses has been determined in sera and matched synovial fluids of patients with rheumatoid arthritis (RA) and compared with that of a healthy control population. The increased level of antibody to Epstein-Barr virus (EBV) induced antigens in patients with RA resembles the antibody pattern observed against cytomegalovirus (CMV) induced antigens, which suggests the presence of a pathological condition in patients with RA that can reactivate latent viral infections. The antibody response against EBV and CMV observed in synovial fluids excludes the local production of specific antibodies against EBV and CMV antigens.

Adult↗

PubMed1986

Rapid diagnosis of viral infections by an alkaline phosphatase immunocytochemical method.

The use of alkaline phosphatase immunocytochemical staining was explored for the rapid diagnosis of poliovirus, adenovirus, herpes simplex virus and cytomegalovirus infections in cell cultures. In this test, viral antigens treated with their relative antibody were incubated with alkaline phosphatase-labelled antisera. The enzyme label was developed with a naphthol salt in the presence of a diazonium salt (Fast Blue) in order to obtain a blue coloured precipitate at the site of the enzyme. It is suggested that this immunocytochemical technique is valuable in the detection of viral infections and would be an appropriate test to use when rapid diagnosis is required.

Adenoviruses, Human↗

PubMed1986

Double immunoenzymatic staining for the simultaneous detection of Epstein-Barr virus induced antigens.

A double indirect immunoenzymatic staining was developed for the simultaneous visualization of Epstein-Barr virus-induced early antigens and virus capsid antigens in P3HR1 lymphoblastoid cell line. The double immunocytochemical staining was performed with a four-stage and a two-stage procedure employing human sera and monoclonal antibodies against Epstein-Barr virus-induced antigens, followed by the addition of specific alkaline phosphatase and peroxidase labeled antisera. The selection of substrates yielding reaction products of contrasting colours enabled the observer to distinguish cells expressing Epstein-Barr virus capsid antigens (blue) from cells expressing Epstein-Barr virus early antigens (brown).

Alkaline Phosphatase↗

PubMed1986

Stimulating effect of heat shock on the early stage of human cytomegalovirus replication cycle.

The effect of mild heat shock on the replication of human cytomegalovirus (HCMV) was studied in human embryo fibroblasts. Treatment of cell cultures at 44 degrees C for 10 min just before infection or at 24 h post infection (p.i.) shortened HCMV eclipse period and enhanced viral replication, while heat shock performed at 48 h p.i. had no effect on the HCMV replication cycle. Study of HCMV-induced early and late antigens confirmed that the cellular response to heat shock influences HCMV replication in the early stage of the viral replication cycle.

Antigens, Viral↗

PubMed1986

Indirect alkaline phosphatase immunoenzymatic staining for the detection of antibodies to Epstein-Barr virus-induced virus capsid antigens and early antigens.

An indirect alkaline phosphatase immunoenzymatic staining technique was developed for the detection of antibodies against Epstein-Barr virus-induced virus capsid antigens and early antigens in cell smears. The presence of antibodies against Epstein-Barr virus-induced virus capsid antigens and early antigens was revealed by a dark blue staining of cells expressing the antigens. The alkaline phosphatase assay gave a permanent record of the reaction that could be visualized under an ordinary light microscope. The titers obtained with this assay on 91 serum samples were significantly correlated with the titers obtained with an immunofluorescence technique.

Alkaline Phosphatase↗

PubMed1986

Detection of specific immunoglobulin M antibodies to cytomegalovirus by using monoclonal antibody to immunoglobulin M in an indirect immunofluorescence assay.

The detection of immunoglobulin M (IgM) antibodies to cytomegalovirus-induced late antigens by an indirect immunofluorescence assay was improved by the use of monoclonal antibodies to human IgM. Nonspecific background fluorescence was absent, facilitating the reading of the slides and the detection of a specific fluorescence reaction in sera with low levels of specific IgM. Moreover, the indirect immunofluorescence assay with monoclonal antibodies to IgM proved more sensitive than the indirect immunofluorescence assay with polyclonal antibodies to IgM. The absorption of human sera on staphylococcal protein A avoided false reactions due to the presence of rheumatoid factor and high levels of specific IgG in test sera.

Antibodies, Monoclonal↗

PubMed1985

Relationship between smooth muscle and cytoskeleton antibodies in neuroblastoma.

The previously reported high prevalence of smooth muscle antibodies in neuroblastoma has been found to be associated with a similarly elevated prevalence of anti-cytoskeleton antibodies. The most relevant finding is related to anti-microfilaments (anti-actin) and anti-microtubules antibodies, which were detected with highly significantly different prevalences when compared with a disease control group (p less than 0.001 and p less than 0.000001, respectively). The correspondence between smooth muscle antibodies and anti-cytoskeleton antibodies is incomplete, and it is more relevant for anti-microfilaments. It is concluded that antigen specificities of smooth muscle antibodies in neuroblastoma are as complex as documented in other diseases. Possible pathogenetic and clinical implications emerging from these data are discussed.

Antibodies↗

PubMed1985

Detection of active Epstein-Barr infection in pregnant women.

Sera taken from pregnant patients and their newborns at delivery were examined for evidence of primary or reactivated Epstein-Barr virus infection. Of 102 women, 37 showed serological signs of reactivated and two signs of primary infection. A mild congenital defect was observed in association with one of the two cases of maternal primary infection. Infants of mothers with reactivated infections remained healthy during the one year follow-up after birth.

Adolescent↗

PubMed1985

Effect of heat shock on Epstein-Barr virus and cytomegalovirus expression.

The effect of heat shock was investigated on lymphoblastoid cell lines Raji and P3HR1 harbouring Epstein-Barr virus (EBV) genomes, and on Vero cells abortively infected with human cytomegalovirus (HCMV). A heat shock at 44 degrees C for 10 min induced the appearance of EBV early antigens in Raji cells and increased the percentage of cells expressing EBV viral capsid antigens in P3HR1 cells. Heat shock performed on Vero cells just before HCMV infection resulted in an approximately fourfold increase in the number of cells exhibiting early nuclear antigens, and in the appearance of HCMV-induced Fc receptors.

Antigens, Viral↗

PubMed1985

Rapid neutralization assay for human cytomegalovirus antibody.

Human cytomegalovirus induces the appearance of immediate early antigens in infected cells 1 h after infection. This provided the basis for the development of a rapid neutralization assay for cytomegalovirus antibody which was able to yield results within a single day. Indirect immunofluorescence to visualize immediate early antigen-positive cells was applied to the rapid determination of cytomegalovirus-neutralizing antibody. The neutralization titers obtained with this assay on 92 serum samples were in accordance with the immune status as determined by enzyme-linked immunosorbent assay to cytomegalovirus-induced immediate early, early, and late antigens.

Antibodies, Viral↗

PubMed1985

Alkaline phosphatase immunoenzymatic staining for detection of antigens induced by cytomegalovirus.

An indirect alkaline phosphatase immunoenzymatic staining method was developed to localise antigens in human embryo fibroblasts that have been induced by cytomegalovirus. The enzyme label was developed with a naphthol salt and fast blue to obtain a bright blue staining of the antigens that could be clearly visualised under an ordinary light microscope. The procedure is rapid, sensitive, and specific and can be used in diagnostic laboratories to detect active infection caused by cytomegalovirus.

Alkaline Phosphatase↗

PubMed1984

Serological screening for the prevention of transfusion-acquired cytomegalovirus infection.

The presence of antibodies against cytomegalovirus (CMV)-induced immediate-early antigens (IEA), early antigens (EA) and late antigens (LA) was sought in 500 healthy blood donors. Antibodies to late antigens were detected in 76% and antibodies to immediate-early and early antigens were detected in 9.6% and 10.2%, respectively. The incidence of antibodies to CMV-induced immediate-early and early antigens increased with age, was higher in females than in males and was related to high values for antibodies against CMV late antigens. Since antibodies to CMV immediate-early and early antigens are significantly associated with active CMV infection, criteria for choosing blood samples unlikely to transmit infective CMV are evaluated.

Adult↗