Biomedical subjects

M Csabayová

Publications and source records attributed to M Csabayová.

5 recordsLinked to original sources

PubMed1996

Conformational changes in pH2-treated human interferon-alpha 2 detected with monoclonal antibodies.

Monoclonal antibodies allowed to demonstrate the existence of alternative antigenic forms of the same molecule as of human interferon (IFN)-alpha 2. Exposure of recombinant IFN to pH 2, although not affecting its bioactivity, induced structural modulation of molecular surface. The antigenic structure of IFN-alpha 2 appeared to be built of the acid-stable and acid-labile epitopes. In general, the acid-stable sites determined subtype-specific antigenic properties of the protein, whereas the acid-labile determinants were responsible for antigenic characteristics shared by some other human IFNs. Acidification of IFN-alpha 2 to pH 2 for at least 1-2 h resulted in simultaneous structural rearrangement of all acid-labile sites.

Antibodies, Monoclonal↗

PubMed1995

Relativity of an antigenic homology between human interferon-alpha 1 and interferon-alpha 2c.

Analysis of an antigenic relatedness between human interferon (IFN)-alpha 1 and IFN-alpha 2 was performed with mapped monoclonal antibodies raised to the respective subtypes. Antigenic properties of immunoreactive domains located in the N-terminal segments 30-67 of IFN-alpha 1 and IFN-alpha 2 were found distinct when compared by neutralization bioassay or ELISA. On the other hand, corresponding domains exhibited an unexpectedly high antigenic homology when tested by Western blot. We suppose that this relativity in antigenic relation lies in the various extent of denaturation of IFN-molecules in bioassay, ELISA and immunoblot. Structural differences of tested antigens may be responsible for a conformation-determined access of antibodies to the shared epitopes.

Amino Acid Sequence↗

PubMed1994

Pseudorabies virus growth factor can be resolved into two active components.

Pseudorabies virus (PRV) growth factor (PRGF) which induces a transformed phenotype in normal MK-2 cells and represses the transformed phenotype of Hela cells was partially purified and resolved into two components (M(r) < 300 and < 180). Each of the PRGF components retained the transforming activity of the original factor in MK-2 cells but lost its transformation-repressing activity in Hela cells. The latter activity of PRGF could be reconstituted by simultaneous application of its two components. Two monoclonal antibodies against gII glycoprotein of PRV were able to neutralize both PRGF activities, thus supporting the previously suggested hypothesis that the PRV gene for glycoprotein gII might be involved in PRGF synthesis.

Animals↗

PubMed1992

Herpes simplex virus type 2 and pseudorabies virus associated growth factors and their role in the latency in vitro.

A putative herpes simplex virus type 2 (HSV-2) growth factor (HSGF-2) was detected in a crude extract from virus infected mouse embryo cells. This factor, similar to previously described pseudorabies virus (PRV) associated growth factor (PRGF) was shown to have ability to morphologically transform non-transformed cells and to repress the transformed phenotype of transformed cells. Both activities could be neutralized with two, out of seven monoclonal antibodies directed against glycoprotein B of HSV-2. Both PRGF and HSGF-2 were detected in human embryo lung cells latently infected with PRV or HSV-2 either at 41 degrees C, or in the presence of phosphonoacetic acid. Human alpha-2 interferon, when present in medium of latently infected cells enhanced the production of both HSGF and PRGF. On the contrary, when latently infected cells were treated with 5-azacytidine the synthesis of both PRGF and HSGF-2 was completely blocked and the virus reactivated from latency replicated to higher titers than in non-treated cells. The role of PRGF and HSGF-2 in the establishment, maintenance and reactivation of latency, as well as in cellular transformation is discussed.

Animals↗

PubMed1992

The glycoprotein B gene and its syn3 locus of herpes simplex virus type 1 are involved in the synthesis of virus-associated growth factor (HSGF-1).

A putative growth factor (HSGF-1) associated with herpes simplex virus type 1 (HSV-1), which is similar to PRGF associated with pseudorabies virus, and/or HSGF-2 associated with HSV-2, was described. Experiments with four syncytial (syn) and four nonsyncytial (syn+) HSV-1 strains showed that the ability of this virus to produce HSGF-1 in infected cells is associated with the syn+ phenotype. Double infection of cells with syn+ and syn strain resulted either in enhancement or complete inhibition of HSGF-1 production, depending on the chosen pair of syn+ and syn strains. The studies with the recombinants between the syn+ strain KOS and syn strain ANGpath in the gene for glycoprotein B (gB) and syn3 locus revealed that the gB gene and its syn3 locus play a role in the HSGF-1 synthesis.

Animals↗