In vivo evaluation of 111In-labeled T-lymphocyte homing in experimental colitis.
Blockade of lymphocyte recruitment to the intestinal mucosa is considered a useful therapy for inflammatory bowel disease (IBD) and anti-alpha4 antibodies have clinical benefit in patients with active Crohn's disease. The aim of this study was to evaluate a scintigraphic technique to assess lymphocyte homing to the colon in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced experimental colitis (TNBS colitis) in vivo.


METHODS
TNBS-sensitized and nonsensitized murine total lymphocytes or CD4+ lymphocytes were radiolabeled with 111In-oxinate. Cells were injected into control mice (n = 5) or mice with TNBS colitis (n = 5). Specific abdominal radioactive uptake was determined by SPECT using a dedicated pinhole system 48 h after cell transfer. Radioactive colon uptake was correlated with histology and colon weight as parameters of inflammation.


RESULTS
The radioactive colon uptake was most evident in mice with TNBS colitis that received sensitized lymphocytes (uptake ratio [mean +/- SEM], 0.51 +/- 0.03 vs. 0.22 +/- 0.04; P = 0.004). The sensitized 111In-labeled lymphocytes exacerbated colitis compared with nonsensitized lymphocytes. The colon uptake correlated well with both colon weight and histologic score (R2 = 0.836 and 0.933, respectively). The use of purified 111In labeled CD4+ lymphocytes resulted in a similar scintigraphic pattern. Administration of an anti-alpha4 antibody decreased radioactivity colon uptake of the (111)In-labeled cells compared with the control antibody in mice with TNBS colitis (uptake ratio, 0.72 +/- 0.14 to 0.33 +/- 0.03; P = 0.012).


CONCLUSIONS
Animal pinhole SPECT can be applied for temporal and spatial analysis of the lymphocyte homing process in experimental colitis. This technique makes possible the in vivo evaluation of therapeutic efficacy of new drugs that interfere with lymphocyte migration. Moreover, colon uptake of radioactivity can be used as a parameter of disease activity in experimental colitis.
Department of Experimental Internal Medicine, Academic Medical Center, Amsterdam, The Netherlands.
Catherine
C
van Montfrans
Roelof J
RJ
Bennink
Kora
K
de Bruin
Wouter
W
de Jonge
Hein J
HJ
Verberne
Fiebo J W
FJ
Ten Kate
Sander J H
SJ
van Deventer
Anje A
AA
Te Velde
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000000981:diagnostic imaging* / Q000276:immunology*; D003092:Colitis / Q000097:blood / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000276:immunology*; D004353:Drug Evaluation, Preclinical; D005260:Female; D007205:Indium Radioisotopes / Q000097:blood / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D011877:Radionuclide Imaging; D016201:Receptors, Lymphocyte Homing / Q000097:blood / Q000276:immunology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014302:Trinitrobenzenesulfonic Acid
D007205:Indium Radioisotopes; D016201:Receptors, Lymphocyte Homing; D014302:Trinitrobenzenesulfonic Acid