Multi drug resistance(MDR) is a major problem in the treatment of cancer and hematological malignancies. This resistance is multi factorial and is the result of decreased intra cellular drug accumulation. This is partly due to the presence of a 170KD intra membranous protein termed P-GLYCOPROTEIN(p-gp) that is an energydependent efflux pump which has increased expression on drug-resistance cells. In this study we identified the presence ofP-gp by staining with Fluorescent Iso Thio Cyanate (FITC) conjugated anti P-gp in acute leukemia patients and flow cytometry in addition to performing immunophenotype analysis and French, American British (FAB) classification. Results revealed that one fifth of leukemic patients exp~essed P-gp and this phenotype was more prevalent in Acute Undifferentiated Leukemia(AUL) and Acute Myelogenous Leukemia (AML) than in Acute Lymphoblastic Leukemia(ALL). Other findings showed a logical relationship between this phenotype and age groups. There was not any association between P-gp+ phenotype and FAB and Immunophenotyping sub classification, but there was a linear relationship between CD34 and CD7 expression and P-gp+ phenotype. The accumulation ofP-gp molecule that was stated as Mean Fluorescence Intensity (MFI) on the blasts membrane ofAUL and AML patients showed marked increase in comparison to ALL. Furthermore MFI in P-gp+ relapsed patients was much more than P-gp+ pretreatment patients.

Myelin-Oligodendrocyte GLYCOPROTEIN (MOG) is an adhesive molecule responsible for myelin sheath structural integrity and maintenance. Patients with spectrum of inflammatory demyelinating disease particularly in central nervous system are reported to have antibodies against this protein. Diseases such as multiple sclerosis, clinically isolated syndrome, neuro-myelitis optica (NMO) spectrum disorders, acute disseminated encephalomyelitis, transverse myelitis and Optic neuritis seemed to have a correlation with anti-MOG antibodies. MRI findings of seropositive cases revealed spinal lesions, particularly in lower segments. For treatment of these patients methotrexate and azathioprine are suggested. Plasmaphresis and intravenous immunoglobulin may be useful too. However fingolimod and interferons can deteriorate the conditions. Finally it is concluded that anti-MOG antibodies can be a biomarker for CNS demyelinating disorders.

Chronic immune thrombocytopenic purpura (ITP) is an autoimmune disease characterized by antiplatelet autoantibodis. The major target of the anti platelet antibodies is platelet membrane GLYCOPROTEIN IIb/IIIa. In order to characterize the immunodominant epitopes in the structure of GPIIIa, the extracellular portions of GPIIIa will be expressed and purified. These antigens will be tested for antigenicity in further investigation. The first segment of GPIIIa which was considered for expression as a recombinant glutathion S-transferase (GST) fusion proteins included IIIa22-262 which encompass amino acid residue 22-262 of the 762 amino acids of GPIIIa. A segment of GPIIIa complementary DNA (cDNA) was subcloned into the 39 end of the Schistosoma japonicum GST gene in the bacterial expression plasmid vector, pGEX 6P-1 (Amersham Pharmacia Biotech). In summary, the expression plasmid vector, pGEX 6P-1 containing segment IIIa22-262 was introduced to E.coli. Saturated overnight culture was used and the bacterial cells were grown to log-phase. IPTG was added to the culture to induce overexpression of fusion protein and the cells were grown for an additional 1-3 hours. Bacterial lysate containing recombinant protein was prepared by sonication. The fusion protein was purified from total cell extract using glutathione-agarose beads. Specificity of the GST-fusion proteins was confirmed on Immunoblot probed with rabbit anti-GST polyclonal antibodies. Precision Protease was used to remove the GST tag. Protein extract and purified products were analyzed by SDS gel electrophoresis. The recombinant GST-fusion protein IIIa22-262 was successfully expressed and purified in large quantities but the yield of the IIIa22-262 peptide after enzyme treatment was low. When a good yield is fully obtained, the purified protein segment will be used for T-cell stimulation in culture.  

AITP mostly occur in children accompanied by variable clinical sings including petechiae, purpura, ecchymosis and severe bleeding. This study has determined and characterized the anti-platelet GLYCOPROTEINs in children with ITP. The aim of this study was to determinate anti-platelet GLYCOPROTEINs (GPs) using MAIPA method. During 18 months 38 children with clinical signs of AITP were studied in Mofid children hospital. To determine anti-platelet antibodies by ELISA technique, washed O negative platelets were used as a source of platelet antigens. MAIPA method was used to detect antibodies against individual platelet membrane GLYCOPROTEIN. The anti-platelet antibodies level above mean+ 3SD of control group was assumed as positive. The results indicated that the platelet count ranges was between 2×109/L and 95×109/L. 63.5 % out of 38 patients were anti-platelet antibodies positive with ELISA method. The correlation between the above patients with anti-platelet antibody positive and clinical signs was 0.4. Results for determination of antibody against platelet GPIIb/IIIa, GPIb/IX and GPIa/IIa using MAIPA method were 44%, 51% and 25% respectively. In conclusion the preference of MAIPA method is the detection of very small amount of antibody. Since MAIPA is the specific method for the detection of antibody against GLYCOPROTEIN antigens, it has the advantage of differentiating immune and non-immune thrombocytopenia.