RESUMO
The second step of immunoglobulin gene alteration consists of somatic hypermutation and class switch recombination. 80th are regulated by activation-induced cytidine deaminase (AID). Methods: Study on possible application of class switch recombination assays for immunoglobulin gene alteration via AID. Cell based assays using AID B lymphocyte and NIH3T3 cell carrying switch substrate; gene transfer using retrovirus system; FACS analysis; PCR and ELISA. Results: DNA sequencing for S region and gamma1CT are the most sensitive and accurate assays. However, gamma1CT assay seemed to be more reliable and applicable. Others are accurate assays but less applicable. Conclusion: gamma1CT determination is the best class switch recombination assay for immunoglobulin gene alteration via AID.
RESUMO
Fructose 1,6 bisphosphate adolase A and C (FPA A4 and C44) have been found to bind specifically to heparin in physiological ionic strength. The researcher found that activity of FPA was inhibited by heparin. The inhibition of FPA A4 and C4 depend on the degree of sulfation. Inhibition activity FPA of heparin increase directly proportional to molecule lenghth. Kinetic studies showed that: inhibitory mode of heparin on FPA was the linear mixed type inhibition, in which velocity can be driven to zero at high heparin concentration