An eosinophil chemotactic lymphokine in the supernatant of lymphokine-activated killer (LAK) cell culture: relationship to interleukin-5.
The administration of interleukin-2 (IL-2) systemically or locally to cancer patients, either alone or in combination with lymphokine-activated killer (LAK) cells, frequently results in eosinophilia. To investigate the mechanism of such eosinophil accumulation, we measured in vitro eosinophil chemotactic activity (ECA) in the supernatant of LAK cell cultures by a modified Boyden's chamber method. Consequently, a potent and specific ECA was found in the cell-free supernatant of LAK cell cultures. On the other hand, no ECA was found in the supernatant of normal lymphocyte cultures, nor in IL-2 itself. This activity plateaued when 3 x 10(6) lymphocytes were incubated with 1000 U/ml IL-2 for more than 3 days. Sephadex G-100 gel chromatography indicated that the molecular weight of this eosinophil chemotactic factor (ECF) was approximately 45,000 Da. The ECF was stable when heated to 56 degrees C for 30 min but was inactivated by trypsin, indicating that the ECF is a lymphokine which has very similar characteristics to those of IL-5. Using ELISA for hIL-5, the IL-5 level in the supernatant of LAK cell cultures increased dose dependently with increasing IL-2 concentrations. These results suggest that IL-5 may be responsible for the local recruitment of eosinophils in IL-2/LAK therapy.
Ishimitsu
T
T
First Department of Surgery, Kyushu University School of Medicine, Fukuoka, Japan.
Torisu
M
M
D000818:Animals; D002478:Cells, Cultured; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002631:Chemotactic Factors, Eosinophil / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D002850:Chromatography, Gel; D004355:Drug Stability; D004804:Eosinophils / Q000502:physiology*; D006168:Guinea Pigs; D006358:Hot Temperature; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D015848:Interleukin-5 / Q000378:metabolism; D015979:Killer Cells, Lymphokine-Activated / Q000378:metabolism*; D008970:Molecular Weight
D002631:Chemotactic Factors, Eosinophil; D007376:Interleukin-2; D015848:Interleukin-5