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C F Ryschkewitsch

Publications and source records attributed to C F Ryschkewitsch.

At least 37 records · Page 2Linked to original sources
PubMed1997

JC virus (JCV) genotypes in brain tissue from patients with progressive multifocal leukoencephalopathy (PML) and in urine from controls without PML: increased frequency of JCV type 2 in PML.

Progressive multifocal leukoencephalopathy (PML) is caused by the human polyomavirus JC (JCV), and there are at least 4 different genotypes of JCV in the United States. Type 1 strains are of European origin, whereas type 2 and 3 strains are of Asian and African origin, respectively. JCV type 4 strains are derived from a type 1/3 recombinant. In this study, the genotype distribution of JCV strains found in brain tissue or cerebrospinal fluid of 50 PML patients was compared with JCV genotypes excreted in the urine of 103 control subjects. Type determination was based on the polymerase chain reaction-amplified partial sequence of the VP1 coding gene and the noncoding region left of ori. Brain tissues from patients with PML were infected with a significantly higher proportion of JCV type 2 strains than were urine samples from the control group (P = .004). This evidence indicates a biologic difference between JCV genotypes and suggests a difference in their potential to cause PML.

Acquired Immunodeficiency Syndrome↗
PubMed1997

JC virus regulatory region rearrangements and genotypes in progressive multifocal leukoencephalopathy: two independent aspects of virus variation.

JC virus (JCV) causes the central demyelinating disease progressive multifocal leukoencephalopathy (PML). JCV strains excreted in the urine are distinguishable from those in PML tissue by the configuration of their regulatory region to the right of ori: the archetypal regulatory region, 267 nucleotides long, is rearranged in PML tissue by deletion and duplication. Within the coding region JCV shows variations as a result of virus evolution. Four major genotypes are distinguishable of which Type 1 is based in Europe and Type 2 in Asia. Here, the regulatory region rearrangements and the viral genotypes of 29 JCV strains from PML brain were determined. Rearrangement patterns and genotypes were not associated. In general, deletions occurred before duplications, but exceptions to this rule exist. Each configuration of the 29 rearranged regulatory regions was unique and could be derived directly from the non-rearranged, archetypal form.

Gene Rearrangement↗
PubMed1996

Genotype profile of human polyomavirus JC excreted in urine of immunocompetent individuals.

The human polyomavirus JC (JCV) causes the central demyelinating disease progressive multifocal leukoencephalopathy in about 5% of AIDS patients. To characterize the type profile of JCV in a control population in the United States, 54 females (10 to 79 years of age; average age, 43.4 years) and 51 males (18 to 94 years of age; average age, 47.9 years) were examined for the excretion of different genotypes of JCV in their urine by PCR followed by direct cycle sequencing. The group consisted of 89 patients of a general medical clinic in addition to 16 healthy volunteers. The overall incidence of JC viruria was 43 of 105 (40.9%) subjects, with a marked increase for those subjects above the age of 30 years. Two men were found to excrete two different types of JCV at the same time, indicating double infections. Of the three different genotypes of JCV identified to date, type 1 strains (European) were the most common in this cohort (64% of total strains) followed by type 2 (East Asian) (18%). No type 3 (East African) strains were detected. Indirect evidence for the existence of JCV type 3 was found in seven individuals (16%) in the form of a type 1/3 recombinant (also called type 4). In addition, a single example of JCV which differs from types 1, 2, and 3 and may represent a phylogenetically older type (type 5) was found in a 59-year-old African-American. Delineation of sequence variations between JCV types is essential for the design of primers for sensitive PCR with clinical samples.

AIDS-Related Opportunistic Infections↗
PubMed1996

Co-infection with two JC virus genotypes in brain, cerebrospinal fluid or urinary tract detected by direct cycle sequencing of PCR products.

The human polyomavirus JC (JCV), which exists in different geographically based genotypes, causes the central demyelinating disease known as progressive multifocal leukoencephalopathy (PML). A coding region recombinant JCV Type 1/Type 3 (Type 4) is excreted in the urine of some 16% of individuals in the USA. In addition, occasional 'crossovers' in viral DNA sequence at type-specific sites in the coding region occur between JCV genotypes amplified from PML brain. For recombination to occur requires the existence of two different genotypes in the same host. Here we provide evidence from direct cycle sequencing of PCR products that different genotypes of JCV can be found in a single tissue sample. After non-type-specific PCR amplification, cycle sequencing produced 'split bands' at type determining sites which were resolved into type or subtype-specific sequences by subcloning of the PCR products. PCR products with split bands at typing sites were found in two brain samples and in one cerebrospinal fluid (CSF) from AIDS patients with PML and in the urine of four immunocompetent individuals. This indicates that co-infection with two viral types does not depend on severe immunocompromise. Combinations of genotypes found were Types 1A & 1B, 1A & 2, 1B & 2 and 2 & 3. In one doubly infected patient the major JCV type excreted in the urine changed within 1 week.

Adult↗
PubMed1996

Characterization of JC virus DNA amplified from urine of chronic progressive multiple sclerosis patients.

Thirty-seven chronic progressive multiple sclerosis (MS) patients, 20 of whom were taking cyclosporine, were examined for excretion of JC virus (JCV) in the urine. Polymerase chain reaction (PCR) amplification of DNA in urinary cell extracts detected JCV in 30% of the MS urines. In the cyclosporine treated group four of 20 (20%) excreted JCV, whereas in the untreated group seven of 17 (41%) excreted JCV. Thus, cyclosporine treatment did not enhance urinary excretion of the virus. A control group consisting of an unselected series of 89 patients donating urine in a general medical clinic and 16 healthy volunteers showed 41% with detectable urinary JCV. Thirty-three percent of the control females excreted JCV (18/54), as did 49% of the control males (25/51). Although the percentage of MS patients excreting detectable virus was not increased compared to the control group, the presence of JCV in the urine provides a convenient source of the virus for further characterization. Genotyping of DNA fragments amplified from the VP1 region indicates mainly the presence of JCV Type 1 in these chronic progressive MS patients. This is also the type that predominates in the control group. An apparent recombinant between Type 1 and Type 3 (African) within the VP1 region, tentatively designated Type 1/3 (or Type 4), was found in both the MS group and the controls. A larger series of MS patients that includes relapsing/remitting disease will be required to determine whether the genotype profile of JCV excreted in the urine of MS patients differs significantly from controls.

Adult↗
PubMed1995

BK virus and a new type of JC virus excreted by HIV-1 positive patients in rural Tanzania.

HIV-1 positive patients from Tanzanian villages near Shirati were examined for urinary excretion of the human polyomaviruses JC and BK using the polymerase chain reaction (PCR). BK virus (BKV) was detected in 11 of 23 individuals tested. The BKV DNA sequences were all closely related to prototype Gardner strain and BKV (DUN). In contrast, a new type of JCV, termed Type 3 [or JCV (Shi)], was identified in seven of these same 23 individuals by comparison with Type 1 and Type 2 sequences of the VP1/intergenic/T antigen region of U.S., European and Asian strains. This suggests that JCV and BKV, although closely related, have different evolutionary histories within the African population. The six BKV regulatory regions amplified all showed the archetypal configuration. However, two of the seven JCV regulatory regions showed rearrangements: a small deletion and an inverted repeat. JCV causes a fatal demyelinating disease, progressive multifocal leukoencephalopathy (PML), in about 5% of AIDS patients in Europe and the U.S.A., but only one case has been reported in Africa. Our results suggest that this rarity of PML is not due to the absence of JCV in the African population.

Adolescent↗
PubMed1995

Capsid protein VP1 deletions in JC virus from two AIDS patients with progressive multifocal leukoencephalopathy.

PCR on 52 cerebrospinal fluid (CSF) specimens and 33 brain biopsies obtained from HIV-1 positive patients utilized pairs of primers from both the early region (JTP) and late region (JLP). In these patients, in whom progressive multifocal leukoencephalopathy (PML) was suspected on the basis of clinical symptoms and magnetic resonance imaging (MRI) studies, eight CSFs (15%) and 14 brain biopsy specimens (42%) contained JCV DNA sequences. In two patients' samples, the CSFs were positive for JCV DNA in the VP1 region using the primer pair for the VP1 region (JLP), but the fragment amplified migrated more rapidly than the 129-bp product obtained from prototype JCV(Mad-1) or the fragment amplified from the antigenic variant of JCV known as Mad-11. These patients died 3-4 months after onset of progressive neurological symptoms. Cycle sequencing of the fragments revealed overlapping deletions of 24 and 27 nucleotides. These strains were of different genotypes, designated strain 107 and strain 206. Computer analysis of the VP1 amino acid sequence predicts that the eight or nine amino acid residue deletions represent a surface loop with a high antigenic index. These naturally occurring deletion mutants are the first examples of a phenomenon observed experimentally in the mouse polyoma virus capsid protein VP2.

AIDS-Related Opportunistic Infections↗
PubMed1994

Type-specific amplification of viral DNA using touchdown and hot start PCR.

Two types of JC virus (JCV) are found in infected brain and kidney tissues. A highly reliable PCR assay to determine viral type in tissue is presented. This type-specific system is analogous to allele-specific PCR used to detect point mutations in cellular genes. Specific amplification of two fragments, using four pairs of type-specific primers, is based on a single nucleotide difference at the 3'-ends of the primers. A combination of three conditions in the PCR reaction was required for specificity: 'hot start', a ramped ('touchdown') cycle profile, and a slightly lowered molar concentration of the specific primers and dNTPs. Efficient yield of PCR product is not lost under these conditions, and even the least selective mismatches (C:A and T:G) provided specific amplification. Type-specific restriction enzyme sites within the amplified fragments confirm type designation.

Base Sequence↗
PubMed1988

A double-label method detects both early (T-antigen) and late (capsid) proteins of JC virus in progressive multifocal leukoencephalopathy brain tissue from AIDS and non-AIDS patients.

A new double-label immunocytochemical method detects JC virus (JCV) early (T-antigen) and late (capsid) proteins simultaneously in cryostat sections of progressive multifocal leukoencephalopathy (PML) brain tissue from both acquired immunodeficiency syndrome (AIDS) and non-AIDS patients. T-antigen is detected with a monoclonal antibody (PAb 416) followed by goat anti-mouse IgG and mouse Clono-PAP, while capsid proteins are detected by a rabbit polyclonal antiserum to capsid proteins followed by biotinylated goat anti-rabbit IgG and streptavidin-alkaline phosphatase conjugate. The substrates are 3,3'-diaminobenzidine and Vector Red I, respectively. With this method some infected glial cells stain for late (capsid) antigens in the nucleus, while others show early protein (large T-antigen) immunoreactivity. The latter are likely to be astrocytes infected abortively or oligodendrocytes in the early stages of a productive JCV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1988

A monoclonal antibody to SV40 large T-antigen labels a nuclear antigen in JC virus-transformed cells and in progressive multifocal leukoencephalopathy (PML) brain infected with JC virus.

Thirty monoclonal antibodies to SV40 large T-antigen were tested for reactivity on the JC virus-transformed hamster glial cell line known as HJC-15. Two of them (PAb 416 and PAb 108) detected a nuclear antigen in both SV40-transformed CCL 75.1 cells and in HJC-15 cells, but not in control cells lacking T-antigen. These same antibodies also labeled a nuclear antigen in hamster tumor tissue derived from HJC-15 cells. In addition, the monoclonal antibody PAb 416 detected a nuclear antigen in progressive multifocal leukoencephalopathy (PML) tissue infected with JC virus, but not in normal brain tissue or tissue from other neurological diseases. Staining by PAb 416 was reduced by prior incubation with hamster anti-JCV tumor serum, suggesting that the polyclonal antiserum to JCV T-antigen may compete for an epitope at or near the PAb 416 binding site.

Animals↗
PubMed1986

Immunocytochemical search for JC papovavirus large T-antigen in multiple sclerosis brain tissue.

The large T-antigens of papovaviruses JC (JCV) and BK share a C-terminal subsequence with myelin basic protein (MBP). Since this sequence functions as a phosphate acceptor site in MBP, expression of a competing T-antigen sequence in oligodendroglia might adversely affect their ability to post-translationally process MBP and thus to maintain myelin. We have used techniques which demonstrate JCV T-antigen in small oligodendroglial cells from progressive multifocal leukoencephalopathy tissue to search for a possible latent JCV infection expressing T-antigen in nine cases of multiple sclerosis (MS) and three normal brains. No cells expressing T-antigen were detected in plaque or periplaque regions of the MS brains or in control CNS tissue.

Adult↗
PubMed1986

JC papovavirus large tumor (T)-antigen expression in brain tissue of acquired immune deficiency syndrome (AIDS) and non-AIDS patients with progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy (PML) is a JC papovavirus infection of the central nervous system in immunocompromised patients. It is well established that demyelination in PML is caused by JC virus infection of oligodendroglia, but whether the nonstructural regulatory protein, large tumor (T) antigen, is detectable in infected human tissue was not known. Using a modification of the peroxidase-antiperoxidase technique, we found T antigen expressed in the nuclei of cells in virus-infected sites in five cases of PML studied, including two with acquired immune deficiency syndrome (AIDS). PML occurs in AIDS at a much higher frequency than in other immunosuppressive disorders, and PML in AIDS may represent a more severe form of JC virus infection of the central nervous system.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Inhibition of binding of hamster antibody to myelin basic protein by a synthetic triproline-containing peptide from JC virus T-antigen.

Antisera raised against porcine myelin basic protein (MBP) in Syrian hamsters were assayed by an ELISA method. The specificity of a high-titered antiserum was probed with synthetic peptides representing a hexapeptide and a decapeptide of the JC virus (JCV) large T-antigen C-terminus which is homologous to the MBP triproline region, a decapeptide from MBP which is encephalitogenic in guinea pigs, and peptides unrelated to MBP, i.e., substance P and poly-L-lysine. In an ELISA inhibition assay, preincubation of the hamster antiserum to MBP with either the JCV T-antigen C-terminal decapeptide or the encephalitogenic determinant inhibited binding activity in a dose-dependent manner. In contrast, the T-antigen C-terminal hexapeptide, substance P, and poly-L-lysine were not inhibitory. These results suggest that the triproline region of MBP can be immunogenic in hamsters, and support the concept that a conformation of the MBP triproline region is shared with certain of its viral homologues. In an effort to detect similar cross-reactive specificities in hamster antisera to JCV T-antigen, sera of 50 hamsters bearing subcutaneous tumors induced by JCV-transformed glial cells were tested for ability to bind to MBP in the ELISA assay. While significant increases in response compared to prebleed levels were observed in about one-fourth of the sera, some of them showed similar increases in binding to other basic proteins such as histones, and the binding to MBP was not inhibited by the triproline-containing decapeptide.

Animals↗
PubMedDate not supplied

Rearrangements of archetypal regulatory regions in JC virus genomes from urine.

The regulatory region of progressive multifocal leukoencephalopathy-type JC virus (JCV) is rearranged in each host by a process of deletion and duplication. Of the more than 40 that have been examined, no two regulatory regions have been rearranged identically in the brain. The substrate for this rearrangement appears to be a highly stable archetypal regulatory region excreted in the urine. Its role as the transmissible form of the virus, although inferred, has never been proven. We have now amplified by PCR and cycle-sequenced the regulatory regions from 48 urinary strains of the virus. We find that the urinary form of the regulatory region is not entirely stable. Short deletions and duplications in the range of 2-16 bp were observed in seven of these strains. One of these, an inverted repeat, is a pattern of rearrangement not yet found in the brain. Two others (#208 and 230) showed a 2-bp deletion at position nos. 221 and 222, and an unusual mutation at position no. 219. These two urines were collected in different states of the USA at different times and analysed months apart. It is very unlikely that these unusual changes represent sample contamination or that they arose independently. This finding indicates that archetypal forms of the JCV regulatory region are infectious, despite their relative inactivity in tissue culture. While changes in the archetypal structure can be found, it is clear that rearrangements in the kidney are rare or rarely infectious.

Adult↗
PubMedDate not supplied

Molecular epidemiology of human polyomavirus JC in the Biaka Pygmies and Bantu of Central Africa.

Polyomavirus JC (JCV) is ubiquitous in humans and causes a chronic demyelinating disease of the central nervous system, progressive multifocal leukoencephalopathy which is common in AIDS. JCV is excreted in urine of 30-70% of adults worldwide. Based on sequence analysis of JCV complete genomes or fragments thereof, JCV can be classified into geographically derived genotypes. Types 1 and 2 are of European and Asian origin respectively while Types 3 and 6 are African in origin. Type 4, a possible recombinant of European and African genotypes (1 and 3) is common in the USA. To delineate the JCV genotypes in an aboriginal African population, random urine samples were collected from the Biaka Pygmies and Bantu from the Central African Republic. There were 43 males and 25 females aged 4-55 years, with an average age of 26 years. After PCR amplification of JCV in urine, products were directly cycle sequenced. Five of 23 Pygmy adults (22%) and four of 20 Bantu adults (20%) were positive for JC viruria. DNA sequence analysis revealed JCV Type 3 (two), Type 6 (two) and one Type 1 variant in Biaka Pygmies. All the Bantu strains were Type 6. Type 3 and 6 strains of JCV are the predominant strains in central Africa. The presence of multiple subtypes of JCV in Biaka Pygmies may be a result of extensive interactions of Pygmies with their African tribal neighbors during their itinerant movements in the equatorial forest.

Adolescent↗
PubMedDate not supplied

JC virus type 2B is found more frequently in brain tissue of progressive multifocal leukoencephalopathy patients than in urine from controls.

OBJECTIVES: Previous studies have shown that strains of human polyomavirus JC (JCV) of Asian origin (type 2) are much more highly represented in progressive multifocal leukoencephalopathy (PML) brain than would be expected from their frequency of excretion in urine samples of a comparable control group. The present studies were designed to test whether one subtype of type 2 was preferentially elevated. STUDY DESIGN/METHODS: The statistical relation between JCV subtypes represented in PML brain tissue from 51 probands and those in urine samples from 115 control individuals was examined. RESULTS: The proportion of the JCV subtype 2B in PML brain (36%) was highly significantly increased relative to its occurrence in control urine samples (5.9%; P < .001). Type 1 and its subtypes were not different in the PML brain and control urine cohorts. The number of type 4 strains in PML brains was reduced, although the difference did not reach statistical significance (P = .08). CONCLUSIONS: The results predict that the human immunodeficiency virus (HIV)-positive individuals at highest risk of PML infection are those carrying the JCV genotype known as type 2B. Prospective studies will be required to confirm this finding.

Adult↗
PubMedDate not supplied

Complete genome of a JC virus genotype type 6 from the brain of an African American with progressive multifocal leukoencephalopathy.

OBJECTIVES: The major genotypes of the human polyomavirus JC (JCV) include type 1 (European), type 2 (Asian), type 3 (African), and type 4 (United States). Here we report characterization of the complete genome of a genotype obtained from the brain of an African American with systemic lupus erythematosus (SLE) and progressive multifocal leukoencephalopathy (PML). STUDY DESIGN/METHODS: DNA extracted from JCV-infected brain tissue was subjected to whole-genome polymerase chain reaction (PCR) amplification and direct cycle sequencing. Relations to other JCV genotypes and the predicted amino acid sequence were analyzed. RESULTS: This African-American type 6 strain (#601) differs from strains of all other genotypes in about 2% of its DNA sequence. The length of the total coding region of strain #601 is increased to 4855 bp by the insertion of a single nucleotide in the large T-antigen intron. This strain, originally placed with the type 2 group on the basis of its sequence in the VT-intergenic region, is very closely related to strains recently identified in the urine of individuals from Ghana, West Africa. CONCLUSIONS: This is the first example of an African JCV genotype identified in the brain of an African-American PML patient. The extent of sequence divergence of JCV type 6 suggests a split of type 6 strains before the separation of types 2 and 3. These findings confirm that distinctive African genotypes of JCV have been maintained in the African-American population and that they are capable of causing PML.

Adult↗