Subcutaneous tubes for chemotactic studies and leucocyte collection

Abstract

For the study of the chemotactic influences of various substances, including bacteria and their products, and for the collection of phagocytes and other wandering cells, small glass test tubes of about 5 c.c. capacity have been placed in the loose subcutaneous tissues of the rabbit. The procedure is as follows.

The mouths of test tubes, 1.2 × 5 cm., are covered with drum heads of fine bolting silk, tied on with thread, which permit free interchange of liquids with the subcutaneous tissues and the migration of cells and bacteria. The chemotactic material or the organism to be studied, either in agar (1 c.c.) overlaid with Ringer's solution, or in fluid form is then added to the sterilized tubes through a hollow needle. A tube may be placed in each flank through a single dorsal incision, after blunt dissection of the loose subcutaneous tissue. Surgical anesthesia and asepsis are required for the operation. Removal of the tube contents is accomplished by hypodermic puncture through the cloth heads of the tubes, after careful cleansing of the skin with iodine and alcohol. The needles of two 20 C.C. syringes are plunged into the tube. One syringe is already filled with Ringer's solution or other liquidto replace the tube contents as it is drawn into the second syringe. Thus the tube is washed out and left full of fresh material. The tubes themselves are practically non-irritating and their contents may be reclovered daily, or at longer intervals, for weeks or months.

From such tubes, containing a small amount of aleuronat in agar and filled up with Ringer's solution, leucocytes for phagocytic experiments may be collected daily over a long period. During the first day few leucocytes enter the tubes, but after 48 hours, and subsequently, a 15-20 C.C. specimen of ground glass opacity may be recovered from each tube.