Debaryomyces is enriched in Crohn's disease intestinal tissue and impairs healing in mice.

Alterations of the mycobiota composition associated with Crohn's disease (CD) are challenging to link to defining elements of pathophysiology, such as poor injury repair. Using culture-dependent and -independent methods, we discovered that Debaryomyces hansenii preferentially localized to and was abundant within incompletely healed intestinal wounds of mice and inflamed mucosal tissues of CD human subjects. D. hansenii cultures from injured mice and inflamed CD tissues impaired colonic healing when introduced into injured conventionally raised or gnotobiotic mice. We reisolated D. hansenii from injured areas of these mice, fulfilling Koch's postulates. Mechanistically, D. hansenii impaired mucosal healing through the myeloid cell-specific type 1 interferon-CCL5 axis. Taken together, we have identified a fungus that inhabits inflamed CD tissue and can lead to dysregulated mucosal healing.

Evaluation of surgical tissue from patients with Crohn's disease for the presence of Mycobacterium avium subspecies paratuberculosis DNA by in situ hybridization and nested polymerase chain reaction.

Crohn's disease (CD) is a chronic inflammatory bowel disease (IBD) with tissue granuloma and histopathological alteration that resembles aspects in tuberculosis, leprosy, and paratuberculosis. Mycobacterium avium subsp paratuberculosis (MAP) is the causative agent of paratuberculosis, with a suspected role in the etiology of CD. We investigated the presence of MAP DNA in 31 surgical tissue samples from 20 subjects using fluorescence in situ hybridization (FISH) with the aid of confocal scanning laser microscopy and nested polymerase chain reaction (PCR) using the IS900 sequence unique to MAP. MAP DNA was detected by PCR in tissue from 10 of 12 (83%) patients with CD: 7/12 (58%) in inflamed, 6/11 (55%) in noninflamed and in 10 (83%) of either tissue and by FISH in 8 of 12 (67%) patients with CD: 7 of 12 (58%) in inflamed, 4 of 11 (36%) in noninflamed, and in 8(67%) of either tissue. In non-IBD subjects, MAP DNA was detected in the tissue of only 1 of 6 patients (17%) by PCR and 0 of 6 patients (0%) by FISH. MAP DNA was identified by PCR in inflamed tissue from 2 of 2 patients with ulcerative colitis. The detection of MAP DNA by either technique in tissue from subjects with CD is significant compared with non-IBD subjects (P < 0.005). Identification of MAP DNA in both inflamed and noninflamed tissue by both techniques suggests that MAP infection in patients with CD may be systemic. The data add more evidence toward a possible association of MAP in the pathogenesis of CD.

Molecular evidence for two forms of Crohn disease.

Recent epidemiological evidence suggests that there are two forms of Crohn disease (CD): perforating and nonperforating. We hypothesized that, just as with tuberculoid and lepromatous leprosy, differences in the two forms of CD would be both identified and determined by differences in the host immune response. Resected intestinal tissue from control patients as well as perforating and nonperforating CD patients was evaluated for mRNA levels. We employed 32P PCR amplification with published or custom-designed primers of a housekeeping gene (beta-actin); a human T-cell marker (CD3-delta); and the cytokines tumor necrosis factor alpha, transforming growth factor beta, granulocyte/macrophage colony-stimulating factor, interleukin (IL) 1 beta, IL-1ra, and IL-6. Differences were identified with IL-1 beta (control = 162 +/- 57 vs. perforating = 464 +/- 154 vs. nonperforating = 12,582 +/- 4733; P < or = 0.02) and IL-1ra (control = 1337 +/- 622 vs. perforating = 2194 +/- 775 vs. nonperforating = 9715 +/- 2988; P < or = 0.02). These data corroborate the epidemiological observation that there are two forms of CD. Nonperforating CD, the more benign form, is associated with increased IL-1 beta and IL-1ra mRNA expression. We conclude that it is the host immune response that determines which form of CD becomes manifest in any given individual and discuss the investigative, diagnostic, and therapeutic implications of these observations.

[Lamprene in ano-perineal lesions of Crohn's disease. A retrospective study]. / Le Lamprène dans les localisations ano-périnéales de la maladie de Crohn. Une étude rétrospective.

UNLABELLED: The efficacy of clofazimine (Lamprene) was analysed retrospectively in twenty one patients with anoperineal lesions (APL) of Crohn's disease. Clofazimine is known for its antimycobacterial, antiinflammatory and immunomodifier properties. It is used with success in leprosy and certain dermatological disorders. A number of clinical and laboratory arguments suggest the probability of a role of mycobacteria in the etiology of Crohn's disease. METHODS: twenty one patients with ileo-colono-anal or bucco-colono-anal Crohn's disease formed the basis of this study. They had been treated in various ways for APL, without success. They had APL of varying degrees of advancement (primary lesions: seven cases; secondary lesions: ten cases; major advanced lesions: four cases). Treatment with Lamprene was given for three to 38 months (mean: 12 months), the mean cumulative dose being 40 grams (4 to 146). Other therapeutic measures were started simultaneously in twelve patients: medical in six cases, medico-surgical in four cases and surgical only in two cases. The aim of treatment in fourteen cases was to obtain the healing of ulcerated lesions and/or fistulas, in three patients to delay dilatation sessions and in four patients to avoid proctectomy in the short-term. RESULTS: ten patients showed no improvement while eleven were improved (with regression of primary lesions in ten cases). Taking combined treatment into consideration, the link between the result obtained and Lamprene was considered probable in five cases, possible in four cases and uncertain in one case. Lamprene was well tolerated in general. It was not possible to evaluate the efficacy of treatment regarding intestinal disease. CONCLUSION: the efficacy of Lamprene in ano-perineal lesions of Crohn's disease is possible and is worthy of evaluation in a controlled trial.

Cell death in granulomata: the role of apoptosis.

Unequivocal apoptosis were seen by light microscopy in examples of leprosy, sarcoidosis, tuberculosis, Crohn's disease and foreign body granulomata. A limited electron microscopic investigation showed typical apoptotic bodies in both sarcoid and leprosy granulomata. The number of apoptosis and mitoses in granulomata were counted and their densities calculated. The wide variation in the results between individual lesions may reflect differences in disease activity.