Twenty unique phage antibodies to human tumor necrosis factor alpha were selected from a naive combinatorial library of human single chain variable fragments. Analysis of gene segments encoding selected antibodies showed that the repertoire of variable domains of heavy and light chains included variable domains of both naive autoantibodies and antibodies produced through somatic hypermutation.

Six unique phage antibodies against human tumor necrosis factor (TNF) were selected from the earlier constructed naïve combinatorial library of single-chain antibodies by affinity selection. The TNF binding of these antibodies was examined by enzyme immunoassay and Western blot analysis. The specificity of the selected antibodies was determined from their binding to interferons alpha and gamma, bovine serum albumin, ovalbumin, and ubiquitin. Two antibodies (sA1 and sB3) were converted into a soluble single-chain antibodies as individual molecules. Their affinity proved to be 2.5 and 13.7 nM, respectively.

Из сконструированной ранее неиммунной комбинаторной библиотеки одноцепочечных антител человека методом аффинной селекции были отобраны шесть уникальных фаговых антител против TNF человека. Связывание отобранных фаговых антител с TNF исследовали методами ИФА и Вестерн-блот-анализа. Специфичность отобранных антител определяли по связыванию с интерферонами альфа и гамма, бычьим сывороточным альбумином, овальбумином и убиквитином. Два антитела, sA1 и sВ3, переведены в формат растворимых одноцепочечных антител в виде индивидуальных молекул; их аффинность составила 2.5 и 13.7 нМ соответственно.

Из неиммунной комбинаторной библиотеки одноцепочечных антител человека методом аффинной селекции отобраны 20 уникальных фаговых антител, направленных к фактору некроза опухолей альфа человека. Анализ генных сегментов, кодирующих отобранные антитела, показал, что репертуар вариабельных доменов тяжелых и легких цепей включает вариабельные домены как первичных наивных аутоантител, так и антител, образованных в результате соматического гипермутагенеза.

Four unique phage single-chain variable fragments (scFvs) to recombinant human interleukin 18 (IL-18) has been selected from a naïve combinatorial library of human scFvs. Binding of unique phage antibodies with IL-18 was tested by ELISA and Western-blotting. No cross reactivity with tumor necrosis factor α, interferons α and γ was shown for the selected antibodies. The gene segments encoding V(D)J regions of selected antibodies exhibited a high degree of homology to germline genes, therefore we suggest that the selected scFv's belong to repertoire of naïve autoantibodies.

KatG Ser3 15Thr mutation is one of the main reasons of resistance to isoniazid in Mycobacterium tuberculosis isolates. The frequency rate of the above mutation among isoniazid-resistant isolates made 94% in Novosibirsk Region and 93% in Kemerovo Region. The use of PCR-restriction fragment length polymorphism (PCR-RFLP) can be regarded as an adequate method for rapid screening of isoniazid resistance in Mycobacterium tuberculosis isolated in the West-Siberian Region.