Increased production of granulocyte-macrophage colony-stimulating factor in Crohn's disease--a possible target for infliximab treatment.

BACKGROUND: The presence of neutrophils among epithelial cells is one of the major features of the inflammation in Crohn's disease, and has been used to indicate disease activity. The survival of neutrophils outside the blood vessels is limited and their longevity is influenced by granulocyte-macrophage colony-stimulating factor (GM-CSF), which probably reduces neutrophil apoptosis. OBJECTIVE: To study GM-CSF production in intestinal cell cultures from Crohn's disease patients before and after infliximab treatment. PATIENTS: Colonic mucosal biopsies were obtained from 29 Crohn's disease patients before and after three infliximab infusions (5 mg/ml) and from ten healthy subjects. METHODS: Biopsies were cultured in RPMI at high concentrations of interleukin-2 (IL-2) (2000 U/ml) and IL-4 (500 U/ml), but without antigen addition. GM-CSF content was analysed after 5 days culture and related to the Crohn's disease activity index (CDAI) and compared with the GM-CSF production from healthy subjects. Peripheral leucocyte count, C-reactive protein and the degree of mucosal inflammation, evaluated histologically, were determined. In-vitro T cell GM-CSF production was studied with/without addition of infliximab and after stimulation. RESULTS: GM-CSF production was increased in Crohn's disease patients compared with healthy controls (P = 0.02) and correlated with the CDAI (Spearman rho = 0.65, P = 0.001). GM-CSF levels and mucosal histology score decreased (P = 0.007 and P = 0.01 respectively) after three infliximab infusions, as did the peripheral blood leucocyte count (P < 0.001). Infliximab inhibited in-vitro T cell GM-CSF production. CONCLUSION: In-vitro cell culture production of GM-CSF was increased in Crohn's disease and related to inflammation, but decreased after infliximab treatment, probably because intestinal T cell GM-CSF production was reduced.

T-cell vaccination in Crohn's disease: principles and presentation of the first two cases.

In Crohn's disease (CD) CD4(+) T-cells producing tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) are important for disease progression. T-cell vaccination with such attenuated (gamma-irradiated) CD4(+) T cells may ameliorate the auto-reactive actions of Type-1 T cells through stimulation of interleukin-10 (IL-10)-producing regulatory T cells. This study aimed to propagate and use gut-derived type-1 CD4(+) T-cells for vaccination in CD. In a case study, two patients with CD-activity index (CDAI) >150 for >1 year were vaccinated with 800 x 10(6) attenuated autologous gut-derived CD4(+) T cells producing Type-1 cytokine -- grown in the presence of high concentrations of only IL-2 and IL-4. The T-cell vaccination was safe, causing only minor redness and tenderness at the injection sites. In Case 2, the treatment brought 3-years with active steroid-resistant CD into remission. CDAI dropped from 171 to 76, CD-endoscopic index of severity fell from 20 to eight and C-reactive protein reduced from 165 to 70 nmol/L. Case 1 received rescue infliximab (there was disease progression before sufficient quantities of cells were ready for the second vaccination). We concluded that it is possible to propagate T cells for autologous vaccination for CD and that treatment was safe. One patient, vaccinated according to the protocol, improved with sustained result for >1 year.