Serum complement C3 cleavage product

C3 is mainly a beta globulin synthesized by macrophages, monocytes, lymphoid tissues, bone marrow, peritoneum, and liver. C3 is further cleaved by the action of C3 lyase and participates in the activation of all complements. The dynamic changes of complement have received increasing attention in clinical practice. The serum total complement and C3 of patients with gastritis caused by antigen-antibody complex decreased significantly. The reduction in serum complement in most patients with systemic lupus erythematosus is associated with worsening conditions. Serum C2, C4, C2, and C3 were decreased in patients with active systemic lupus erythematosus, and serum complement levels returned to normal when the condition was relieved. Basic Information Specialist classification: cardiovascular examination classification: blood examination Applicable gender: whether men and women apply fasting: fasting Tips: Do not eat too greasy, high-protein foods the day before the blood draw, avoid heavy drinking. The alcohol content in the blood directly affects the test results. After 8 pm on the day before the medical examination, fasting should be done to avoid affecting the detection of indicators such as blood glucose in the second sky. Normal value One-way immunodiffusion method was 0.0094 g/L (negative lysate <10%). Clinical significance The dynamic changes of complement have received increasing attention in clinical practice. The serum total complement and C3 of patients with gastritis caused by antigen-antibody complex decreased significantly. The reduction in serum complement in most patients with systemic lupus erythematosus is associated with worsening conditions. Serum C2, C4, C2, and C3 were decreased in patients with active systemic lupus erythematosus, and serum complement levels returned to normal when the condition was relieved. Infectious diseases and tissue damage and acute inflammation, C2, C3, C4 increased, and total complement activity was normal or elevated. But the late stage is reduced. The increase in the amount of complement in patients with cancer, especially in liver cancer, is the most obvious increase in C3 and is of diagnostic significance. It has also been reported that C3 is decreased in patients with advanced pancreatic cancer and recessive lymphocytic leukemia. C3 in patients with liver disease is mostly reduced, and the level of C3 in renal transplant patients is unstable. C3 rises at the beginning of rejection and then falls below normal. High results may be diseases: lupus erythematosus, tumor, pancreatic cancer, leukemia considerations (1) Be careful to avoid air bubbles when pouring agar plates. (2) The pipette used to dilute serum and antiserum must be fixed. Dilute the reference serum and patient serum using a uniformly calibrated pipette, otherwise use the same pipette. Other equipment is also best unified. (3) The agar concentration used must be strictly controlled, and prevented from drying after dispensing. Do not dissolve repeatedly. Do not boil for too long when dissolved, and evaporate with water. The temperature of 56 °C should be strict, too hot will destroy the serum, too cold and easy to coagulate. Mix quickly and fully. (4) The position after the serum is added must be kept horizontal to prevent deformation of the diffusion ring. (5) The serum of the subject must be fresh. If the conditions are not allowed, the serum can be stored frozen or diluted and stored. It will have little effect within a few days. After a long time, the C3 value will increase. Inspection process First, the tested serum was diluted 5 times with 0.1 g/L thiomersal physiological saline, and then added to the corresponding wells of the agar plate in sequence (each plate should be used for more than 5 different concentrations of C3 reference serum as a control). The agar plate was dehumidified. Inside, the measurement results were measured after 37 ° C for 48 h. The obtained C3 reference serum precipitation ring diameter is compared with the corresponding value on the originally drawn standard curve. The sedimentation ring of the lowest concentration C3 reference serum should not be 0.1 mm larger than the original, the highest concentration is not more than 0.3 mm, and the other three concentrations are not more than 0.2 mm. Otherwise, it should be re-measured. Not suitable for the crowd There are no special taboos. Adverse reactions and risks No relevant records.