Antibody drug carrier for immunotherapy of superficial bladder cancer: ultrastructural studies.

Superficial bladder cancer represents a promising target for intravesical, antibody-guided therapy. The construction of an optimum antibody-cytotoxic drug conjugate depends mostly on the appropriate selection of a monoclonal antibody (mAb). We have used immunogold labeling and SEM to specifically map the distribution of antigens expressed on three bladder cancer cell lines and on the luminal surface of biopsies from human transitional cell carcinoma of various grades and from normal bladder mucosa.

Immunogold labeling of the low-affinity (55 kd) IL2 receptor on the surface of IL2 receptor-bearing cultured cells and mitogen-activated peripheral blood lymphocytes.

Foreign antigens or mitogens initiate activation of T lymphocytes through antigen-specific receptors. After antigen-receptor interaction, T cells release a lymphotrophic hormone, interleukin 2 (IL2), and high-affinity IL2 receptors (IL2R) are progressively expressed on their surfaces. When evaluated under the scanning electron microscope after specific immunolabeling with colloidal gold markers, the density of expression of the 55 kd low-affinity IL2 receptor (Tac) increases in a time-dependent manner, reaching a maximum 72 hours after the onset of phytohemagglutinin (PHA) activation.

Scanning electron microscopic study of immunogold-labeled human leukocytes.

For many years critical point drying (CPD) has been the method of choice for preparing cells for scanning electron microscopy (SEM). Described herein is a simple, efficient, inexpensive, reproducible, and safe procedure using Peldri II, a proprietary fluorocarbon compound that is solid at room temperature and a liquid above 25 degrees C, as a sublimation dehydrant for processing specimens for SEM. The utility of Peldri II was demonstrated in studies using leukocytes from the blood of healthy donors and patients with leukemia as well as from long-term lymphoblastoid cell lines.

Effects of halothane on arrhythmias induced by myocardial ischaemia.

The effect of halothane on arrhythmias induced by ischaemia was investigated in rats, isolated perfused rat hearts, and pigs. Responses to the occlusion of the left anterior descending coronary artery were determined in groups (n = 9) of chronically prepared rats treated with no halothane, 0.5, or 1.