Expression of ICAM-1 enhances in vivo lymphocyte adhesion in a murine fibrosarcoma.
OBJECTIVE
ICAM-1 is essential for lymphocyte-endothelial cell interactions. We have demonstrated that increased expression of ICAM-1 in tumors results in an enhanced response to adoptive immunotherapy. We undertook this study to determine whether increased expression of ICAM-1 results in increased lymphocyte adhesion in vivo.


METHODS
Parental MCA-105 tumor cells were cotransfected with ICAM-1 and the NeoR plasmid. A neomycin resistant clone (Cl149) was selected and increased expression of ICAM-1 confirmed by FACS analysis. Tumor fragments (MCA-105 or Cl149) were placed in a dorsal skin-fold chamber on day 0 in C57BL/6 mice. Lymphocytes were fluorescently labeled using 0.5% acridine orange and activity recorded on videotape at 700x magnification. Lymphocyte activity was quantitated over 30 second intervals in postcapillary venules as either passing or rolling/sticking (R/S). The % R/S was calculated for each category and evaluated using chi 2 analysis.


RESULTS
Whereas 38% of lymphocytes were classified as R/S in normal tissue, 32% were classified as R/S (P > .05) in the MCA-105 tumor. However, in the ICAM-1 transfected CL149, there was significantly greater R/S at 53% (P < .05).


CONCLUSIONS
These data demonstrate increased lymphocyte adhesion in tumors with enhanced expression of ICAM-1 by direct in vivo observations and may partially explain the salutary effect of increased ICAM-1 expression on adoptive immunotherapy. This suggests the possible application of adhesion molecule expression in the cellular therapy of cancer.
Turner
J
J
Department of Surgery, University of Maryland School of Medicine, Baltimore, USA.
Rhee
J G
JG
Fabian
D F
DF
Lefor
A T
AT
D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D004730:Endothelium, Vascular / Q000502:physiology; D005260:Female; D005354:Fibrosarcoma / Q000139:chemically induced / Q000378:metabolism*; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism* / Q000502:physiology; D008214:Lymphocytes / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018715:Microscopy, Video; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1