the investigators objective is to identify the association of SNP polymorphisms in the TNFS4, and NCF gene and SLE Egyptian patients.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by clinical heterogeneity with variable severity. Among the SLE patients, two may share the same clinical manifestations but have different phenotypes.

This is why studies are searching for the different genes that might be associated with SLE susceptibility.

The Neutrophil cytosolic factor (NCF) Gene provide the instruction for the synthesis of group of proteins that form the NADPH oxidase enzyme complex, that is critical for the induction of reactive oxygen species (ROS) which in turn is important in the regulation of immune system.

While the Tumor necrosis factor superfamily 4 (TNFSF4) encodes the ligand for OX40 (OX40L), which delivers a strong costimulatory signal to activated effector T-cells and enhances both Th1 and Th2 responses when engaged with its receptor. Therefore, increased levels of cell surface OX40L may augment B cell differentiation and proliferation. The consequence of which is that the resulting autoantibodies and immune complexes cause disease pathology in SLE.

So, NCF and TNFSF4 gene polymorphism are supposed to be associated with SLE risk and pathophysiology.

Inclusion Criteria:

• SLE patients
• patients older than 18 years old

Exclusion Criteria:

• patients with other connective tissue diseases
• patients older than 70 years old