Studies of cytosolic and microssomal of lymphocytes B cell fractions of patients with chronic lymphocytic leukemia. A differentiate proteomic analysis

• Grant number: 05/01573-8
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2005
• End date: September 30, 2007
• Field of knowledge: Biological Sciences - Biochemistry
• Principal Investigator: José César Rosa
• Grantee: José César Rosa
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Chronic lymphoproliferative diseases (CLD) represent a highly heterogeneous group of diseases characterized by an accumulation of mature lymphoid cells. Chronic lymphocytic leukemia (CLL) is the most common CLD. Median patient age at diagnosis is 65 years, with the disease being rare (10%) among persons younger than 50 years. The incidence is 5 cases per 100,000 inhabitants per year which, projected for Brazil, indicates the existence of 1,500 new cases per year. In Western countries, CLL represents 30% of all leukemias, in contrast to Asian countries, where it only corresponds to 5% of the total. CLL can be classified on the basis of the rearrangement of the VDJ genes of the immunoglobulin heavy chain (IgVH), with two variants known as mutated (MUT) and non-mutated (UNMUT) or naïve. In the present study, the profile of protein expression will be evaluated by proteome analysis in mononuclear cells from an initial number of 10 cases of CLL and from healthy individuals selected by immunophenotyping. The experimental approach will consist of: (i) isolation of mononuclear cells from patients with a diagnosis of CLL who are already enriched with B lymphocytes. As a control, B lymphocytes isolated from human peripheral blood of healthy individuals will be isolated by immunomagnetic separation; (ii) preparation of protein maps by two-dimensional electrophoresis (2DE); (iii) identification of differentially expressed proteins by mass spectrometry; (iv) construction of a database gel documenting the levels of protein expression, the mass spectra acquired and functional notations of the proteins identified, using a free access software in the XML format (www.openoffice.org) which will permit making the data available on the internet. The protein profile to be established may contribute to the diagnosis and prognosis and also demonstrate possible targets for the development of new therapies. (AU)