Preliminary Research On PR1Specific Cytotoxic T Lymphocytes Of Chronic Myeloid Leukemia Patients Accepted Different Treatment

Objectives:Chronic myeloid leukemia is one of myeloid malignancies. There is no effective treatment method to CML present. It’s ideal methods of tyrosine kinase inhibitor (TKI) that specifically targets the BCR-ABL oncoprotein and adoptive immunotherapy. For the past few years, immunomodulation mediated by Glivec(TKIs) and interferona(IFNa) has become more and more interesting and argument. In this thesis, we used the soluble HLA-A*0201/PR1tetramer as a tool to detect the frequency of the PR1specific cytotoxic T lymphocytes(PRl-CTLs) of chronic myeloid leukemia patients. And we had researched the immune function effect of Glivec and interferon for CML, and offer clinical experiment data to develop a more effectively cure for CML in clinic.Subject:CML PatientsMethods:AT first, we followed up30patients diagnosed CML in chronic phase which were treated with Hydroxycarbamid (Hu), IFNa and Glivec respectively.Then monitored the changes of their hemogram, bone marrow cells, Philadelphia chromosome (Ph) and BCR-ABL fusion gene. To investigate the Curative effect of the three treatments, we analysed their hematologic remisson rate (HR), cytogenetic remission rate (CyR), molecular effect rate (MR) and median time.Then, in order to detect the frequency of the PR1specific cytotoxic T lymphocytes of CML, we constructed PR1peptide HLA-A*0201single chain timer(SCT) with the genetic engineering technology and use BirA enzyme for biotinylation. Biotinylated SCT and PE marked streptavidin mixed according to the mole ratio of4:1to make PR1HLA-A*0201tetramer as testing tool to detect PRl-CTLs in vitro.At last, we collected CML patients’bone marrow or peripheral blood sample and separated PBMC.Then we screened HLA-A*0201positive patients (17/45,37.8%) with HLA-A*0201monoclonal antibody. Further more, we used the soluble PR1HLA-A*0201tetramer as a tool to detect the frequency of PR1-CTLs of11CML patients with HLA-A*0201positive.The11patients were consist of5cases treated with Glivec,3cases treated with IFNa and3patients were diagnosed newly.Results:1、The results showed the three groups are effective in CHR,100%,88.9%and66.7%respectively. The CHR median time of Glivec group is23d, shorter than Hu and IFNa group (75d、64d respectively) obviously. In the Glivec treatment group,t he CCyR is72.7%and the median time is6months, the MR is50%and the median time is18months. In the IFNa treatment group CyR is44.4%, the median time extended as long as27.5months, but no patients had MR. None of the HU treatment group patients showed CyR or MR.2、We found that PR1HLA-A*0201tetramer combined with PR1-CTLs electively,we can use the PR1HLA-A*0201tetramer as the tool to analysis PR1-CTLs.3、Our study suggest that PR1-CTLs of newly diagnosed group is very low (0.02±0.02), the PR1-CTLs of IFNa treatment group and Glivec treatment group higher (0.1167±0.025,0.12±0.014) than newly diagnosed group (P<0.05). While PR1-CTLs of IFNa and Glivec groups were not statistically different (p=0.823). There is negative correlation between PR1-CTLs and Sokal score (r=-0.892, P<0.001)Conclusions:1、The study suggested that we can use the PR1HLA-A*0201tetramer as the tool to analysis PR1-CTLs, it is foundation for following researches.2、PR1-CTLs play an important role in the immunological surveillance and immune function reconstruction of CML patients and influence CML patients prognosis.3、There is negative correlation between PR1-CTLs and Sokal score, the result suggest that the lower tumor load the lower Sokal score, the high PR1-CTLs frequency may stand for good prognosis.