Development of 3 Multi-PCR Based Microsatellite Instability Analysis (MSA) for Bladder Cancer Detection

Several studies have shown that microsatellite changes can be profiled in urine for the detection of bladder cancer. Use of microsatellite analysis (MSA) for bladder cancer detection requires a comprehensive analysis of up to 15 to 20 markers, which were based on amplification and interpretations of many individual MSA markers and can be technically challenging. Here, in a way to develop fast, more efficient, standardized and less costly MSA for detection of bladder cancer, we have developed 3 multiplex PCR based MSA assay, all of which were analyzed by genetic analyzer. First, we have selected 16 MSA markers based on 9 selected publications. Based on samples from Johns Hopkins University (JHU Sample, first set sample), we have attempted to develop MSA assay based on doublet, 2 tube based multiplex PCR combined with singlet, 1 tube based single plex PCR. While this assay was initially successful, we have encountered a reproducibility issue and we then developed MSA based on triplet, 3 tube based multiplex PCR (Triplet MSA assay). From second set samples (6 cancer patients’ and 14 normal individuals’ sample), our Triplet Assay with 15 MSA markers correctly predicted all of 6/6 cancer samples to be cancerous sample and 14/14 samples from normal individuals as normal samples. This result suggests that our Triplet MSA Assay combined with genetic analyzer is a potentially time and cost-effective genetic assay for bladder cancer detection and can be used potentially as a dependable assay in patient care.

“Protenuria in SLE: Is it always lupus?”

Proteinuria is one of the most typical manifestations of kidney involvement in Systemic Lupus Erythematosus (SLE). We report the case of a 23-year-old woman with a 6-year-long history of SLE presenting with proteinuria after a three-year remission on hydroxychloroquine. Kidney histological examination showed alterations inconsistent with lupus nephritis and suggestive of hydroxychloroquine toxicity or Fabry disease. The latter was confirmed by genetic assay.

Seewis hantavirus in common shrew (Sorex araneus) in Sweden

Background Rodent borne hantaviruses are emerging viruses infecting humans through inhalation. They cause hemorrhagic fever with renal syndrome and hemorrhagic cardiopulmonary syndrome. Recently, hantaviruses have been detected in other small mammals such as Soricomorpha (shrews, moles) and Chiroptera (bats), suggested as reservoirs for potential pandemic viruses and to play a role in the evolution of hantaviruses. It is important to study the global virome in different reservoirs, therefore our aim was to investigate whether shrews in Sweden carried any hantaviruses. Moreover, to accurately determine the host species, we developed a molecular method for identification of shrews. Method Shrews (n = 198), caught during 1998 in Sweden, were screened with a pan-hantavirus PCR using primers from a conserved region of the large genome segment. In addition to morphological typing of shrews, we developed a molecular based typing method using sequencing of the mitochondrial cytochrome C oxidase I (COI) and cytochrome B (CytB) genes. PCR amplified hantavirus and shrew fragments were sequenced and phylogenetically analysed. Results Hantavirus RNA was detected in three shrews. Sequencing identified the virus as Seewis hantavirus (SWSV), most closely related to previous isolates from Finland and Russia. All three SWSV sequences were retrieved from common shrews (Sorex araneus) sampled in Västerbotten County, Sweden. The genetic assay for shrew identification was able to identify native Swedish shrew species, and the genetic typing of the Swedish common shrews revealed that they were most similar to common shrews from Russia. Conclusion We detected SWSV RNA in Swedish common shrew samples and developed a genetic assay for shrew identification based on the COI and CytB genes. This was the first report of presence of hantavirus in Swedish shrews.

Morphological-cultural and molecular genetic features of collection strains of mycoris mushrooms Phialocephala fortinii and Pezicula sp.

A metagenomic analysis of the endophytic microflora of Vaccinium corymbosum L. and Vaccinium myrtillus L. root systems was carried out. Two dominant species of micromycetes forming ericoid mycorrhiza were identified - Phialocephala fortinii C. J. K. Wang & H. E. Wilcox and Pezicula sp. Tul. & C. Tul. Pure cultures of mycorrhizal fungi were prepared, a comprehensive morphological and genetic assay of the strains was carried out. Based on the results of genetic-taxonomic analysis, the assumption of the polyphyletic origin of species belonging to Phialocephala and Pezicula is confirmed.

AB0996 FAMILY CASE OF BLAU SYNDROME IN 3 CHILDREN, INITIALLY DIAGNOSED AS JUVENILE IDIOPATHIC ARTHRITIS

Background:Juvenile Idiopathic Arthritis (JIA) is heterogeneous group of diseases which may include genetically determined conditions. Extremely rare monogenic hereditary autoinflammatory disease, such as Blau syndrome (BS) is usually difficult to recognize and JIA is initially established. BS is caused by a mutation in the NOD2/CARD5 gene and phenotypically characterized by triad of granulomatosis polyarthritis, uveitis and skin rash.Objectives:To present the family case of genetically confirmed BS in 2 siblings, initially diagnosed as patients with JIA.Methods:Two brothers of 15 and 3 years old were examined in our clinic. Additional genetic assay was performed because of unusual clinical picture.Results:Case report.Older brother, 15 y.o. developed arthritis of both wrist joints at the age of two. There was erythematous maculo-micropapular scaly rash on the trunk and extremities before the onset of arthritis. By 2009 (5 y.o.), the knees, ankles, and three PIP joints of the left hand were involved. Polyarthritis was characterized by severe effusion and periarticular tissues swallowing. He was treated in regional hospital by NSAID, methotrexate, cyclosporine A without significant positive effect. Since 2012 etanercept was added for treatment with variable result. Inactive status of the disease is never reached. Repeated intra-articular GC injections were needed from 4 to 10 times per year. The patient was admitted to our clinic in November 2019. He was suffering from severe polyarthritis and uveitis de novo (granulomatous chorioretinitis) was detected. At the same time his younger 3 y. o. brother with recently started disease was hospitalized in our clinic. He had polyarthritis with typical features of “boggy” synovitis and tenosynovitis of wrists, ankles and knees, anterior uveitis was determined. The onset of arthritis was preceded by a small-spotted rash with desquamation. This classical clinical features in younger brother let us suggest the BS. There was no increasing of ESR and CRP in both sibs throughout the course of the disease. A molecular genetic study of the NOD2/CARD15 gene in both brothers revealed the same mutation of c.1001G>A (p. Arg334Gln). Because of the absence of specific treatment for this disease and due to insufficient effect of etanercept with uveitis de novo therapy was changed to golimumab and good initial effect is reached. The youngest brother has started his therapy by methotrexate. It should be noted that the family has the eldest brother (20 y.o.), who has been suffering from arthritis since an early childhood with similar clinical picture. We are going to perform genetic analysis of the NOD2/CARD15 gene for the eldest brother.Conclusion:Our clinical case shows that extremely rare BS may be misdiagnosed as JIA. Lack of efficacy of the etanercept therapy and uveitis de novo developing may be caused by genetic (non-idiopathic) nature of disease. Classic triad of boggy-arthritis, granulomatous uveitis and/or skin lesions without acute phase markers is required to perform genetic assay for the detection of a pathogenic mutation of the NOD2/CARD15 gene. This case is remarkable by the presence of BS in two (or 3) children of the family.References:[1]Wouters C.H, Maes A, Foley K, et al. Blau Syndrome, the prototypic auto-inflammatory granulomatous disease. Pediatric Rheumatology. 2014; 12: 33.Disclosure of Interests:None declared

Titration of in-cellula affinities of protein-protein interactions

A genetic assay permits simultaneous quantification of two interacting proteins and their bound fraction at the single-cell level using flow cytometry. In-cellula affinities of protein-protein interactions can be extracted from the acquired data through a titration-like analysis. The applicability of this approach is demonstrated on a diverse set of interactions with proteins from different families and organisms and with in-vitro dissociation constants ranging from picomolar to micromolar.

An Assay to Study Intra-Chromosomal Deletions in Yeast

An accurate DNA damage response pathway is critical for the repair of DNA double-strand breaks. Repair may occur by homologous recombination, of which many different sub-pathways have been identified. Some recombination pathways are conservative, meaning that the chromosome sequences are preserved, and others are non-conservative, leading to some alteration of the DNA sequence. We describe an in vivo genetic assay to study non-conservative intra-chromosomal deletions at regions of non-tandem direct repeats in Schizosaccharomyces pombe. This assay can be used to study both spontaneous breaks arising during DNA replication and induced double-strand breaks created with the S. cerevisiae homothallic endonuclease (HO). The preliminary genetic validation of this assay shows that spontaneous breaks require rad52+ but not rad51+, while induced breaks require both genes, in agreement with previous studies. This assay will be useful in the field of DNA damage repair for studying mechanisms of intra-chromosomal deletions.