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Biomedical subjects

R Manservigi

Publications and source records attributed to R Manservigi.

At least 55 records · Page 3Linked to original sources
PubMed1989

Nucleoside analogs as non-substrate inhibitors of herpes simplex viruses thymidine kinase.

We have examined the capacity of a series of 6-substituted pyrimidine and 2-substituted purine derivatives to inhibit mammalian thymidine kinase and the thymidine kinases encoded by type 1 and type 2 herpes simplex viruses. Several N2-substituted guanine and deoxy guanosine derivatives displayed selective inhibitory activity against the HSV-1 and HSV-2 thymidine kinases by competing with the phosphorylation of thymidine, suggesting a possible novel pharmacological approach to herpes viruses infections.

Cells, Cultured↗
PubMed1988

An isoelectric focusing study in herpes simplex virus encephalitis.

To establish an early reliable diagnostic test for herpes simplex virus (HSV) type 1 encephalitis (HSVE), we used isoelectric focusing (IEF) and an IEF-overlay technique with radiolabeled HSV glycoprotein B (gB) to study 7 serum and 12 cerebrospinal fluid (CSF) samples from 12 patients with presumed or biopsy-proved HSVE. Blood-brain barrier damage and increased intra-blood-brain barrier IgG synthesis were detected in 5 of the 7 patients with HSVE. CSF oligoclonal bands were found in 6 of 11 patients. Using an IEF-overlay technique, we detected anti-gB antibody in all serum (7 of 7) and in 10 of 12 CSF samples. Anti-gB antibody was found in 4 of 6 CSF specimens obtained within the first week of disease (days 3 to 5) and in all samples collected later in the disease. The pH range of anti-gB antibody activity was broad (4.5 to 9.5), indicating a heterogeneous immune response to HSV. A hematogenous origin of the CSF antibody was suggested because anti-gB antibody appeared in serum before matched CSF and because both serum and matched CSF had a similar antibody IEF pattern. Local production of anti-gB antibody was suggested in some cases because of a greater prominence of anti-gB antibody in CSF than in matched sera and because CSF oligoclonal bands had anti-gB antibody activity. In contrast, only one of 6 CSF samples from patients with multiple sclerosis had gB antibody activity; in this case, anti-gB antibody activity did not correspond in isoelectric point location to oligoclonal bands.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

A herpes simplex virus type 1 mutant resistant to benzhydrazone, an inhibitor of glycoprotein synthesis in herpesvirus-infected cells. Preliminary mapping of benzhydrazone-resistance and of a novel syncytial mutation.

Benzhydrazone (BH) is an inhibitor of glycoprotein biosynthesis. It acts selectively in Herpes simplex virus (HSV)-infected cells and does not significantly affect glycoprotein synthesis in uninfected cells and in cells infected with other viruses. Previously, we reported on a syncytial (syn) mutant, designated HSV-1(13)S11, resistant to BH, and showed that BH-resistance is encoded in the mutant virus DNA and therefore can be transferred into the genome of wild type HSVs. The present paper reports on a preliminary mapping in HSV-1(13)S11 genome of the loci which confer resistance to BH and of three distinct syn mutations present simultaneously in this mutant. Two of them were mapped in previously described syn loci localized in BamHI fragment L (map units 0.707-0.745) (locus syn 1) and BamHI fragment Q (map units 0.296-0.317) (locus syn 5). A third mutation not described before and mapping in BamHI fragment SP (c.a. map units 0.81-0.85) conferred the syn phenotype to both HEp-2 and Vero cells. This novel mutation has been designated herein locus syn 6. Transfer of BH-resistance could be achieved in cotransfection experiments involving two HSV-1(13)S11 fragments, BamHIL and BamHISP.

Animals↗
PubMed1988

Constitutive expression in human cells of herpes simplex virus type 1 glycoprotein B gene cloned in an episomal eukaryotic vector.

Expression of herpes simplex virus type 1 (HSV-1) glycoprotein B (gB-1) was obtained in human cells from the gB-1 gene cloned in the episomal replicating vector pBK-1, which contains the origin of replication and early region of the human papovavirus BK. Selective systems for the TK+ phenotype in TK-143B cells and for resistance to G418 in adenovirus 5-transformed 293 cells were used to obtain stable transformants that produced gB-1. While gB-1 expression in 143B cells required induction by HSV-1 early proteins, constitutive gB1 production was observed in 293 cells, where endogenous trans-acting factors probably replace the need for early viral products in the activation of the cloned gB-1 gene. The amount of recombinant gB-1 was comparable to that produced during HSV-1 lytic infection in human cells, due to amplification of the inserted gene in the replicating episomal vector. Expression of gB-1 was induced by cadmium and zinc when the promoter of the mouse metallothionein-I gene was placed upstream of gB1 structural sequences. The inducible system where the gB-1 gene is under the control of its own promoter could be employed to clarify the role of early viral products in induction of gB-1 synthesis. Constitutive expression of gB-1 in human cells could provide useful material for diagnostic purposes and for the preparation of a subunit vaccine against HSV infections.

Blotting, Southern↗
PubMed1986

Sequences homologous to two separate transforming regions of herpes simplex virus DNA are linked in two human genital tumors.

Ten human genital invasive squamous cell carcinomas and five human premalignant tissues were analyzed for the presence of selected sets of herpes simplex virus 2 (HSV-2) DNA sequences. Two vulvar tumors and one vulvar dysplastic tissue were found to contain DNA sequences homologous to the BglII O fragment (coordinates 0.38-0.42) and the BglII N fragment (coordinates 0.58-0.63) of HSV-2 DNA. These two fragments overlap the subsets of HSV-1 and HSV-2 DNA sequences (respectively) shown previously to transform cells in culture. Sequences homologous to an additional HSV-2 DNA probe (BglII G) were not detected in the same tumors. Surprisingly, in each of the two positive vulvar tumors, the BglII N and BglII O sequences appeared to be linked, whereas in the standard HSV-2 genome the two fragments are separated by approximately 26 kb. This finding suggested that the two sets of sequences may have rearranged prior to or following the association of the HSV DNA sequences with the tumor cells. The same set of 10 tumors were analyzed for the presence of sequences complementary to human papillomavirus 16 (HPV16) DNA. The HPV16 DNA probe hybridized to three of six cervical tumors, whereas no hybridization was detected with the two vulvar tumors which contained the HSV DNA sequences.

Cell Transformation, Viral↗
PubMed1986

Search for HSV DNA in genital, cerebral and labial tumors.

DNA sequences homologous to HSV-1 and HSV-2 DNA fragments were searched in 64 genital, 35 labial and 34 cerebral tumors. Southern blot transfers of tumor and control DNAs were hybridized in stringent conditions with 32P labelled probes from HSV-1 and HSV-2 cloned DNA fragments. Specific hybridization to HSV-2 BglII N fragment was observed in six (9.4%) genital tumors. Labial and cerebral tumors did not show hybridization to any of the probes used. The technique employed allowed the detection of 0.1 copies of viral fragments per diploid genome.

Base Sequence↗
PubMed1985

Evidence for glycoprotein abnormality in platelets from patients with May-Hegglin anomaly.

In the present research protein analysis on SDS-polyacrylamide gel electrophoresis (PAGE) has been used to study the glycoprotein pattern of the blood platelets of four members from a family affected by May-Hegglin anomaly. In order to characterize the glycoprotein fractions, lactoperoxidase-iodination and immunoprecipitation procedures were used. N,N'diallyltartardiamide (DATD) cross-linked gel electrophoresis was shown to improve the glycoprotein pattern resolution, although with the lactoperoxidase-iodination the glycoprotein characterization of May-Hegglin platelets overlapped the normal. On the other hand with the immunoprecipitation the specific antiserum precipitated all the five major fractions of normal membrane glycoproteins, but it was shown to react quite poorly with the component V of the May-Hegglin glycoprotein pattern.

Antigens↗
PubMed1985

Analysis of HSV isolated from patients with unilateral and bilateral herpetic keratitis.

Restriction enzyme analysis was utilized to investigate 11 HSV isolates from patients with herpetic keratitis. The electrophoretic profiles of the DNAs indicate that the isolates belong to HSV-1 and are epidemiologically unrelated. Two of the isolates, derived from a patient with simultaneous bilateral herpetic keratitis were further characterized by genetic and phenotypic analyses. These studies showed the following: (i) the two recrudescent lesions were caused by the same HSV-1 isolate; (ii) the isolate yielded two different plaque phenotypes; (iii) these plaques showed different sensitivity to I.D.U.

Acyclovir↗
PubMed1985

Characterization of virus obtained from MDBK cells persistently infected with a variant of herpes simplex virus type 1 strain MP [HSV-1(MP)].

Virus clones which express glycoprotein gC (gC+) were obtained from two persistently infected (p.i.) MDBK cell lines which had been independently established by infection with HSV-1(MP)10311, a gC- syncytial (syn) variant of herpes simplex virus type 1 strain MP [HSV-1(MP)]. The gC+ revertants were syn in MDBK, HEp-2, and Vero cell lines and in primary human fibroblasts; this offers further evidence that glycoprotein gC does not inhibit cell fusion. The gC+ revertants represented from 70 to 100 percent of the virions present in the virus populations examined, thus suggesting a possible selective advantage of the gC+ revertants in this system of persistent infection.

Animals↗
PubMed1985

Establishment and characterization of a persistent infection of MDBK cells with herpes simplex virus.

A persistent, dynamic-state infection of a variant of herpes simplex virus type 1 strain MP [HSV-1 (MP)] in MDBK cells was established without supportive measures and maintained for over three years by routine passaging of the cells at 7-9 day intervals. The infection was characterized by a cyclic pattern of monolayer damage and reconstitution, correlated with virus production, which was most evident when the interval between subcultures was intentionally prolonged and the cells were left undisturbed. Occasional periods of cell crisis, with increased virus replication and extensive cytopathology, occurred. Passaging of the cells at higher density avoided eventual loss of the culture during the most severe crises. Presence of specific antibodies did not alter the course of infection. Interferon was constantly found during periods of cell crisis; it appeared on the second day after subculture, reached a maximum in correspondance of the first peak of cytopathology, and disappeared well before the onset of the second wave of cytopathology. Addition of exogenous interferon cured the cells of infection. Defective interfering particles could not be found. Virus isolated during persistence differed from parental virus regarding plaque morphology, temperature sensitivity of growth, and electrophoretic pattern of infected cells glycoproteins. A discussion on the possible mechanisms of persistence is provided.

Animals↗
PubMed1985

Defective expression of neutrophil membrane proteins in patients with rheumatoid arthritis.

At least 14 iodinated proteins can be distinguished by SDS polyacrylamide gel electrophoresis followed by autoradiography in the membrane of intact human neutrophils. Neutrophils from patients suffering from rheumatoid arthritis show a modified expression of 4 outer membrane proteins. Three polypeptide components of the 30, 50 and 130 K were decreased by 95%, while the 120 K component dramatically increased. The possible relationship between the altered cell sensitivity and the defective expression of membrane proteins is discussed.

Adult↗
PubMed1984

Pyrazolo[4,3-d]pyrimidine nucleosides. Synthesis and antiviral activity of 1-beta-D-ribofuranosyl-3-methyl-6-substituted-7H-pyrazolo[4,3-d]pyr imi din-7-ones.

N1 analogues of formycin B, with substituents at the 3 and 6 positions of the pyrazolo[4,3-d]pyrimidine moiety were synthesized by the direct SnCl4-catalyzed ribosylation method. The site of the glycosidic linkage and the anomeric configurations were established on the basis of X-ray crystallography, as well as 1H and 13C nuclear magnetic resonance spectroscopy. Preliminary results of the antiviral testing of these derivatives in vitro are described.

Animals↗
PubMed1984

Characterization of a herpes simplex virus type 1 mutant resistant to benzhydrazone, a selective inhibitor of herpesvirus glycosylation.

Benzhydrazone [BH; 1H-benz[f]indene-1,3(2H) -dionebis(amidinohydrazone)] significantly inhibits glycosylation of proteins, but only in cells infected with herpes simplex virus. We report on a herpes simplex virus type 1 (HSV-1) mutant resistant to BH. A syncytium-inducing mutant designated HSV-1(13)S11 was found to be biochemically resistant to BH in that [14C]glucosamine incorporation was not inhibited in infected HEp-2 cells exposed to the drug. Intertypic recombinants were obtained which showed that BH resistance is encoded in the DNA of the mutant virus and may be transferred into the genome of BH-sensitive HSV. In the recombinants the biochemical resistance marker segregated from the syncytial marker, suggesting that the two markers probably map in different loci. The BH-resistant mutant did not complement wild-type BH-sensitive HSV-1 and -2. Furthermore, resistance was apparent in HEp-2 but not in Vero cells. The paper discusses the hypothesis that inhibition of glycosylation of HSV proteins is the consequence of modification or selective transport of BH involving a HSV gene product.

Carcinoma, Squamous Cell↗
PubMed1984

Herpes simplex virus latency in immunosuppressed mice.

To determine the role of antibodies in establishing Herpes simplex virus (HSV) latency, immunosuppressed Swiss mice were experimentally infected in the right hind footpad with a HSV-1 x HSV-2 recombinant (C6D) with low virulence. Immunosuppression was induced by repeated intraperitoneal inoculations of Cyclophosphamide (CY) and the production of antibodies to C6D in immunosuppressed animals was monitored by Enzyme Linked Immunosorbent Assay (ELISA). Within 21 days after inoculation, C6D was able to establish a latent infection of lumbosacral spinal ganglia in both normal and CY-treated immunosuppressed animals. The data presented indicate that detectable production of antibodies is not necessary to induce HSV latency in spinal ganglia.

Animals↗
PubMed1983

Herpes simplex virus and human cancer. III. Search for relationship of herpes simplex antibodies and cervical dysplasia and labial neoplasia.

We employed the enzyme-linked immunosorbent assay (ELISA), indirect hemagglutination (IHA), and complement fixation (CF) methods to measure antibody titer to herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in patients affected by labial tumors or cervical dysplasias. No relationship of antibody titer to HSV-1 and labial tumors was detected by any of the three methods. Association between antibody titer to HSV-2 and cervical dysplasias was revealed by IHA (p less than 0.05) and ELISA (p less than 0.001); CF tests were negative. Moreover, we assayed for HSV-specific antigens in cell cultures derived from labial tumors and cervical dysplasias. In cultures from labial tumors, it was not possible to detect HSV-specific antigens. Of the 25 cultures derived from cervical dysplasias, HSV antigens were found in only 3 cultures.

Adult↗
PubMed1980

Comparative analysis of the virion polypeptides specified by herpes simplex virus type 2 strains.

This paper reports on the variability of structural polypeptides of 32 strains of Herpes simplex virus 2 (HSV-2) isolated from various locations in the United States and Italy. Most strains were passaged a limited number of times at low multiplicity outside the human host; a few strains were characterized by numerous passages at variable multiplicities in cell culture. The acrylamide gel electrophoresis of polypeptides from purified virions revealed very few differences. Considering these differences the HSV-2 strains analysed can be classified into 3 groups according to the variability of three polypeptides. The study of polypeptides in HSV-2 infected cells revealed more differences than those seen in the structural proteins. Comparisons of the structural proteins specified by HSV-2 and HSV-1 virions, revealed clear variant features of the electrophoretic profiles, especially when pH of main gel was 8.9.

Electrophoresis, Polyacrylamide Gel↗