Biomedical subjects

L G Vugler

Publications and source records attributed to L G Vugler.

5 recordsLinked to original sources

PubMed1992

Oligomerization of the human cytomegalovirus major envelope glycoprotein complex gB (gp55-116).

The disulfide-linked glycoprotein B (gB; gp55-116) complex of human cytomegalovirus represents the most abundant and immunogenic component of the virion envelope. We have studied the oligomerization and transport of this molecule, using a series of murine monoclonal antibodies. Our results indicated that oligomerization of this molecule occurred shortly after its synthesis, with a half-time of maximal formation of approximately 25 min. The oligomeric form had an estimated mass of 340,000 Da and likely consisted of a homodimer of the gp55-116 complex. By using a conformation-specific monoclonal antibody, postoligomerization folding of this molecule was demonstrated. This event exhibited an unusually prolonged half-maximal time of approximately 160 min. Both oligomerization and folding occurred in the endoplasmic reticulum. Oligomerization and folding occurred in the absence of carbohydrate modifications, although likely at lower efficiency. Finally, the oligomeric and folded forms were shown to be transported to the surface of infected cells and infectious virions.

Antibodies, Monoclonal↗

PubMed1990

Antiviral antibody responses in mothers and their newborn infants with clinical and subclinical congenital cytomegalovirus infections.

Human cytomegalovirus (HCMV)-specific antibodies were assayed in cord serum and the respective maternal serum from two groups of newborn infants with congenital HCMV infection. One group of infants exhibited clinically apparent infection with multiple organ system involvement, whereas the second group had subclinical infections. Levels of virus-specific IgG antibodies reactive with several virus-encoded proteins including those reactive with the major envelope glycoprotein complex were significantly higher in cord serum and maternal delivery serum from the group of infants with clinically apparent infection than in serum from those with subclinical infection. Maternal delivery serum from the group with subclinical infection had significantly higher levels of IgM virus-binding antibody and lower levels of IgG virus-binding antibody than did the respective serum from the group with clinically apparent infection, suggesting maternal acquisition occurred later in gestation in the group with subclinical infection. These results suggested that deficiencies in the HCMV-specific antibody response were not associated with clinically apparent congenital infection and that other factors, such as early virus acquisition during pregnancy, might contribute to the severity of intrauterine HCMV infection.

Antibodies, Viral↗

PubMed1990

Structural and immunological characterization of human cytomegalovirus gp55-116 (gB) expressed in insect cells.

The gene encoding the major envelope glycoprotein complex, gp55-116 (gB), of human cytomegalovirus (HCMV) was expressed at high levels in insect cells utilizing a recombinant baculovirus. The mature intracellular form of the insect-derived gp55-116 was a protein of Mr 150K which contained approximately 50K of N-linked oligosaccharides. The oligosaccharide linkages were almost exclusively endoglycosidase H-sensitive. The 150K protein was processed, presumably by proteolytic cleavage, to yield at least one of the previously defined cleavage products of the gp55-116. This processing step was significantly less efficient in insect cells than the analogous step in mammalian cells. Finally, the insect-derived gp55-116 was highly immunogenic in experimental animals and readily recognized by antibodies contained within HCMV-immune human serum, suggesting that this recombinant protein warrants further study as a potential HCMV subunit vaccine candidate.

Animals↗

PubMed1989

Processing of the gp55-116 envelope glycoprotein complex (gB) of human cytomegalovirus.

The processing pathway of the major envelope glycoprotein complex, gp55-116 (gB), of human cytomegalovirus was studied using inhibitors of glycosylation and endoglycosidases. The results of these studies indicated that the mature gp55-116 is synthesized by the addition of both simple and complex N-linked sugars to a nonglycosylated precursor of estimated Mr 105,000. In a rapid processing step, the Mr 105,000 precursor is glycosylated to a protein of Mr 150,000 (gp150) which contains only endoglycosidase H-sensitive sugar linkages. The gp150 is then processed relatively slowly to a Mr 165,000 to 170,000 species (gp165-170), which is then cleaved to yield the mature gp55-116. Monensin prevented the final processing steps of the gp150, including cleavage, suggesting that transport through the Golgi apparatus is required for complete processing. Digestion of the intracellular forms of this complex as well as the virion forms confirmed the above findings and indicated that the mature virion form of gp55 contains 8,000 daltons of N-linked sugars. The virion gp116 contains some 52,000 to 57,000 daltons of N-linked carbohydrates and approximately 5,000 daltons of O-linked sugars.

Acetylglucosaminidase↗

PubMed1986

An inhibitor typing scheme for Streptococcus uberis.

A typing scheme was used to test 15 strains of Streptococcus uberis according to their production of (P-type) and sensitivity to (S-type) bacteriocin-like inhibitory substances. Twelve of the strains were inhibitor producers and nine different P-types were detected. All of the strains were typable according to inhibitor sensitivity, ten different S-types being distinguished. Both the P-type and S-type designations of the strains were reproducible on repeated testing. By combination of P-typing and S-typing, highly discriminatory inhibitor 'fingerprints' of the strains could be obtained. This scheme would appear to have considerable potential for typing isolates of Str. uberis as an aid to investigations into the epidemiology of Str. uberis mastitis in dairy cattle.

Animals↗