Malaysia first reported H5N1 poultry case in 2004 and subsequently outbreak in poultry population in 2007. Here, a recombinant gene encoding of peptide epitopes, consisting fragments of HA1, HA2 and a polybasic cleavage site of H5N1 strain Malaysia, was amplified and cloned into pET-47b(+) bacterial expression vector. DNA sequencing and alignment analysis confirmed that the gene had no alteration and in-frame to the vector. Then, His-tagged truncated HA protein was expressed in Escherichia coli BL21 (DE3) under 1 mM IPTG induction. The protein expression was optimized under a time-course induction study and further purified using Ni-NTA agarose under reducing condition. Migration size of protein was detected at 15 kDa by Western blot using anti-His tag monoclonal antibody and demonstrated no discrepancy compared to its calculated molecular weight.
The aim of this study was to isolate stem cells from dental pulp of primary molars and incisors to be used as possible source for tissue engineering. Human primary molars and incisors were collected from subjects aged 4-7 year-old under standardized procedures. Within 24 hours, the tooth was cut at the cemento-enamel junction using hard tissue material cutter. The dental pulp tissue was extracted, digested and then cultured in Alpha Modified Eagles's Medium (α-MEM) supplemented with 20% FCS, 100 mM L-ascorbic acid 2-phosphate, 200 mM L-glutamine and 5000 units/ml Penicillin/Streptomycin. The cells were observed daily under the microscope until confluence. Children's tooth pulp- derived progenitor cells were found positive for stem cell markers CD105 and CD166, which are consistent with the finding for mesenchymal stem cells (MSCs) from bone marrow.