Dr. Srinu Tumpara

Detection of short transcripts of SERPINA1 gene in patients with PiZZ liver and lung diseases

We demonstrated that human peripheral blood leukocytes express not only a transcript corresponding to the size of the full-length alpha1-antitrypsin (AAT) protein but also 358 bp (ST1C4) and 248 bp (ST1C5) short transcripts of AAT, which include two last exons. In silico sequence analysis revealed that short transcripts have an Open Reading Frame (ORF) in exon V and thus putatively can produce peptides. A high up-regulation (up to 10-fold) and release of short C-terminal transcripts of AAT was observed in isolated human blood neutrophils after their activation with lipopolysaccharide. This finding gave a novel insight into the transcription of SERPINA1 gene and prompted us to develop monoclonal antibody that specifically recognizes a short C-terminal peptide of AAT but does not react with full-length AAT. Consequently, we raised the hypothesis that changes in expression levels of SERPINA1 gene as well as its short transcripts contribute to the liver and/or lung pathology in individuals with inherited PiZZ AAT deficiency.

Aims:

Aim1. To determine any putative differences and similarities in the occurrence and localization of Cpeptide of AAT in lung and liver tissues of PiMM and PiZZ cases.

Aim2. To find out whether C-terminal peptide of AAT is a component of Z-AAT polymers, and/or is associated with other plasma proteins. Quantitative assays to measure C-terminal peptide in human plasma, will allow us to find putative differences in peptide levels among PiMM and PiZZ cases with and without liver/lung disease.

Aim3. To investigate differences between AAT and C36 expression and localization in neutrophils isolated from PiMM and PiZZ patients, and to answer a question if augmentation therapy affects ZAAT and C36 expression in blood neutrophils. By using specific antibodies against full-length AAT and short C-terminal transcript of AAT, we expect to show the occurrence and tissue distribution of short fragments of AAT, and to reveal their association with PiZZ genotype and liver/lung disease development.

CV

Srinu Tumpara received BSc. in Biotechnology Osmania University, Hyderabad, India and MSc. in Biotechnology, Bharathidasan University, Tiruchirappalli, India. Between 2011-2016 he obtained master's degree in the field of Agro biotechnology, at Justus Liebig University, Giessen, Germany.

Srinu is currently a PhD student- laboratory of molecular pneumology (head Prof. Dr. Sabina Janciauskiene) at the department of Respiratory Medicine, Hannover Medical School, Germany. His PhD thesis and current interests are related to the characterization of the molecular forms and biological activities of AAT protein in subjects with PiMM and PiZZ genotype. Srinu Tumpara has good experience in primary human cell culture techniques, and basic methods in protein chemistry and molecular biology.