An suitable adjuvant is blended with microgram or milligram amounts of immunogen and injected at multiple site of the mouse at various times in a repetitious manners. At times the mice is bled and examination for antibodies of purposed specificity is made. Highest concentration of antibodies are established after the mouse is immense with 2-3 individual delicate doses of antigen. When concentration of antibodies are maximum the mouse is sacrificed and the spleen is taken. Then it is separated into individual spleenocyte by applying enzyme or instrumental process. Lymphocytes of the spleen is separated from rest of the organelles by Density gradient centrifugation .