IMMUNOHISTOCHEMICAL STUDY OF DEPIGMENTED SKIN OF VITILIGO PATIENTS.

Immunohistochemical analysis was used to study depigmented skin areas such as macular of depigmentation and skin perimakular areas in vitiligo patients. It has been shown that the cells containing melanocytic cell marker TRP1 are localized both in macular and perimakular areas. Within the macula of depigmentation all TRP1 positive cells are in close contact with the basement membrane. In perimakular areas many cells that have lost contact with the basement membrane, were localized deep in the epidermis. About 92 % of TRP1 positive perimakular cells were also vimentin positive. Vimentin positive cells were numerous in perimakular areas but missing in the macula of depigmentation. Dense groups of cells immunopositive for transcription factor Snail, known as inductor of epithelial-mesenchymal transition, were localized in perimakular areas in close proximity to the macula depigmentation border. Such cells were extremely rare within the macula of depigmentation. There is reason to assume that an intensive process, which is similar to the epithelial-mesenchymal transition, might be the cause of melanocyte death in perimakular field, and thus prevents repigmentation of depigmented areas.

Immunization with influenza A NP-expressing vaccinia virus recombinant protects mice against experimental infection with human and avian influenza viruses.

Two-fold immunization of Balb/c mice with a vaccinia virus recombinant expressing the NP protein of influenza A/PR8/34 (H1N1) virus under the control of a strong synthetic promoter induced specific antibodies and protected animals against low-dose challenge by mouse-adapted heterosubtypic variants of human A/Aichi2/68 (H3N2) and avian A/Mallard/Pennsylvania/10218/84 (H5N2) influenza virus strains. The surviving immunized animals had lower anti-hemagglutinin antibody titers compared to non-immunized mice. There was no difference in viral titers in lungs of immunized and non-immunized animals that succumbed to the infection. In order to try to increase immune system presentation of NP-protein-derived peptides, and thereby increase their immunogenicity, we constructed another vaccinia-based NP-expressing recombinant containing a rapid proteolysis signal covalently bound to the NP protein. This sequence, derived from the mouse ornithine decarboxylase gene has been shown to increase degradation of various proteins. However, we found that when used as part of a recombinant NP, this signal neither increased its proteolytic degradation, nor was it more efficient in the induction of a protective response against influenza infection.

[Production of noninfectious virions of the Rous sarcoma virus by virogenic hamster cells]. / Produktsiia neinfektsionnykh virionov virusa sarkomy Rausa virogennymi khomiachkovymi kletkami.

Noninfectious virions morphologically identical with avian type C virus virions were produced in Rous sarcoma virus-transformed virogenic hamster cells. The population of the virions contained the major internal protein of avian oncornavirus. It is assumed that production of defective RSV virions occurred in the cells. The major internal protein of avian oncornaviruses was found to be incorporated into the virions containing in their membrane interspecies antigens of hamster oncornavirus produced spontaneously in the system under study. Thus, phenotypic mixing of avian and animal type C viruses in mammalian cells has first been observed.

[Characteristics of the type C virus produced by Rous sarcoma virus-transformed hamster cells]. / Kharakteristika virusa tipa C, produtsiruemogo khomiachkovymi kletkami, trasformirovannymi virusom sarkomy Rausa.

Production of hamster type C virus in Rous sarcoma virus-transformed hamster cells is described. This virus preparation was shown to contain the antigen of the major inner protein of avian type C viruses (p27). The population of virions produced by such cells consists of either of virions of two types (99%--99.9% virions type C of hamster and 0.1%--1% virions the core capsule of which is formed from Rous sarcoma virus p 27) or of virions phenotypically mixed with regard to the major inner protein. The latter possibility seems less likely.

[Detection of a common antigenic determinant in the major inner protein of unrelated oncoviruses]. / Vyiavlenie obshchei antigennoi determinanty v glavnom vnutrennem belke nerodstvennykh onkovirusov.

A new heterologous system of radioimmunoassay (p24 of bovine leukemia virus--antiserum to Rous sarcoma virus) has been developed which demonstrated for the first time the existence of a common antigenic determinant in the major inner protein of unrelated oncoviruses: avian leukemia-sarcoma virus, bovine leukemia virus, mammalian type C viruses (mouse, hamster, monkey) and type D viruses (simian Mason-Pfizer virus). These data suggest a common origin of unrelated oncoviruses and open new approaches for the search of unknown agents associated with human and animal neoplastic diseases.

A new virion precipitation test for oncovirus envelope antigens which detects common antigenic determinants in mammalian type-C viruses and Mason-Pfizer monkey virus.

A method for the study of oncovirus envelope antigens was developed, bases on the precipitation of intact virions by a double antibody technique. The amount of precipitated virus was then measured as reverse transcriptase activity. The method was designated the virion precipitation test (VPT). It has been used for titration of antibodies to envelope antigens of oncoviruses. The study of envelop antigens of 11 different oncoviruses permitted their differentiation into the following groups: (1) murine type-C viruses: (2) feline type-C viruses; (3) simian type-C viruses; (4) the RD-114/BEV group; (5) Mason-Pfizer monkey virus (M-PMV); (6) bovine leukemia virus; (7) avian type-C viruses; (8) mouse mammary tumor virus. No common antigenic determinants were detected in the last three groups. Mammalian type-C viruses (RD-114, NIH-MuLV, G-MuLV) had common antigenic determinants in the envelope, as demonstrated with an anti-RD-114 serum. Mammalian type-C viruses also shared antigenic determinants with M-PMV. The relationship of type-C viruses to M-PMV decreased in the following order: RD-114--NIH-MuLV--G-MuLV. It was also shown that the endogenous xenotropic feline RD-114 virus was more closely related to xenotropic NIH-MuLV than to ecotropic G-MuLV. The nature of the common antigenic determinants, as demonstrated by VPT on the surface of mammalian type-C viruses and M-PMV, and their significance for the concept of oncovirus evolution are discussed.

[Detection of common antigenic determinants in the envelopes of mammalian type D (Mason--Pfizer) and type C virions by using the virion precipitation reaction]. / Vyiavlenie obshchikh antigennykh determinant v obolochkakh virionov tipa D (Mezon--Pfaizer) i tipa s mlekopitaiushchikh s pomoshch'iu reaktsii pretsipitatsii virionov.

Immune sera to Mason-Pfizer virus (M-PMV) are capable of precipitating type C viruses of mice (NIH-MuLV, G-MuLV, and to a lower degree R-MuLV), cats (FeLV, RD-114), and monkeys (SSV-1, GALV, BEV). The immune sera to RD-114, BEV, SSV-1 and GALV viruses can precipitate M-PMV virions. The adsorption analysis suggests that cross-reactions between M-PMV, RD-114, NIH-MuLV, and G-MuLV viruses depend on common virus-specific antigenic determinants in the envelopes of the virions. The relationship between M-PMV and type C viruses decreases in the series RD-114--NIG-MuLV--G-MuLV. Type C viruses of mammals have common envelope antigenic determinants lacking in M-PMV. No common antigenic determinants with M-PMV have been found in the envelope of virions of bovine leukemia virus, type B virus of mice (MMTV), or type C avian virus (Pr-RSV).

[Virion precipitation reaction based on determination of reverse transcriptase activity: Method of study of membrane antigens of oncornaviruses]. / Reaktsiia pretsipitatsii virionov, osnovannaia na opredeleniia obratno-transkriptaznoi aktivnosti: Metod izucheniia obolochennykh antigenov Onkornavirusov.

A method for the study of the envelope antigens of oncornaviruses of C, B, and D types by the virion precipitation test (VPT) based on the measurement of the amount of precipitated virus by its reverse transcriptase activity is described. The method is immunologically specific for titration of antibody to the envelope antigens of oncornaviruses. By means of the VPT it is possible to identify oncornaviruses, to study antigenic relationships between them and to detect some or other antigens in virion coat.

[Reproduction of leukovirus RD-114 in diploid and heteroploid human cells]. / Reproduktsiia leikovirusa RD-114 v diploidnykh i geteroploidnykh kletkakh cheloveka

The capacity of leukovirus RD-114 to replicate in human embryo lung diploid cell cultures and continuous human angiosarcoma cell cultures (AS and 709 lines). Differences in the capacity to support the virus reproduction were observed in the two strains of human embryo lung cells (HEL-1 and HEL-3) and the two continuous angiosarcoma cell lines. No virus reporduction was observed in mouse and rat cell cultures. No cytopathic or transformation changes were caused by the virus in any of the systems examined.