Figure 2

Apoptosis, necrosis and destructive changes in gut cell wall of tumor-engrafted animals under different treatment regimens. A) Viability of Krebs-2 ascites isolated from animals treated with CP and/or hDNA. Flow cytometry plots are presented, and percent of viable cells is indicated (top panel). Microscopy analysis of Krebs-2 ascites following different treatments (bottom panel). B) Progression of apoptosis assayed as the degree of fragmentation of nucleosomal DNA isolated from ascitic fluid (ascites cells removed) on day 3 after CP + hDNA or CP + ICL-hDNA treatment. Typical apoptotic DNA ladder of nucleosome-size fragments (arrows) is present in DNA from ascitic fluid of treated, but not untreated animals (control). Numbers 1–3 denote ascitic DNA samples obtained from three individual animals. C) Degree of necrosis as assayed by LDH levels in ascitic fluid on day 3 after the treatments indicated (P < 0.05, Mann–Whitney U-test, n = 3-6). D) Pathology analysis of several affected tissues from animals treated with hDNA preparations and CP: 1 – abdominal wall skin: subdermal necrosis focus (arrow), E – epidermis; 2 – magnified view of necrosis focus: bottom right – subcutaneous tissue (SC), top left – necrotic detritus (arrow); 3 – intestinal mucosa villi appear rounded as a result of ongoing destructive process (arrow), epithelium is almost entirely gone, stroma appears swelled, with infiltrating lymphocytes present. Taken together, these features are consistent with a pathomorphology pattern of acute enteritis; 4 – extensive mucosal swelling, remnants of villi and pronounced inflammatory infiltration with lymphoid cells. Arrow points to sclerotic mucosa (section of normal intestine is shown in Additional file 1). These features are morphologically compatible with the signs of chronic enteritis. E) Sterility cultures of hDNA preparation and ascites grown in mice: 1 – 5-day ascites; 2 – 9-day ascites; 3 – hDNA (1 mg total).