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D Scheel-Toellner

Publications and source records attributed to D Scheel-Toellner.

22 records · Page 2Linked to original sources

Comparative study of CD26 as a Th1-like and CD30 as a potential Th2-like operational marker in leprosy.

In the last years we have been able to establish CD26 as an operational marker for a human Th1-like reaction in various granulomatous diseases. Recently, CD30 was described as a marker for a Th2-type reaction, where CD30 is preferentially expressed and its soluble form released by human T cell clones producing Th2-type cytokines. To evaluate the possibility of CD30 as an eventual operational marker for a human Th2-like reaction in vivo, we performed immunohistological stainings on frozen sections of skin biopsies from patients with lepromatous and tuberculoid leprosy. A maximum of three to four CD30-positive cells was found per section, and there was no difference in the accumulation of CD30-positive cells between the tuberculoid and the lepromatous form of leprosy. With respect to CD26-positive cells, a high number was found in tuberculoid leprosy in contrast to a greatly reduced expression of CD26 in lepromatous leprosy. We conclude that, while CD26 was confirmed as an operational marker for a Th1-like reaction in leprosy, CD30 does not represent an operational Th2 marker in this disease.

Biomarkers↗

The use of reverse transcription polymerase chain reaction to analyse large numbers of mRNA species from a single cell.

A PCR method is described for determining the expression of multiple heterogeneous mRNAs from single cells. The total mRNA pool of a single selected cell is subjected to reverse transcription and subsequent tailing with poly(dA). This cDNA is preamplified by a sequence non-specific PCR protocol using oligo(dT)-containing primers. The single cell cDNA library obtained permits the analysis of virtually unlimited numbers of mRNA species per cell using sequence-specific PCR. This procedure of multiple mRNA analysis enables phenotyping of any cell for its mRNA composition and could be used to study the cytokine mRNA expression of individual human T cells ex vivo. The method should greatly facilitate the analysis of combinatorial expression of known genes in any cell.

Base Sequence↗

The human germinal centre cells, follicular dendritic cells and germinal centre T cells produce B cell-stimulating cytokines.

Cytokine gene expression was investigated in the germinal centre constituents of follicular dendritic cells and germinal centre T cells and compared to the mRNA expression of nongerminal centre tonsillar cells. Cells were isolated from human tonsils by preenrichment with MACS and subsequent FACS sorting. Cytokine gene expression was investigated by intronspanning RT-PCR for IL-1 alpha, IL-1 beta, IL-2, IL-4, IL-5, IL-6, IL-10, IFN-alpha, IFN-beta, IFN-gamma, and TNF-alpha. Frequency of cytokine-producing cells and the cytokine production pattern of single cells were determined by single cell PCR. Furthermore, cytokine protein expression was investigated by immunohistology. Using these methods, we found a strong production of IL-1 beta mRNA and protein in a small percentage of FDC. Germinal centre T cells showed production of IL-2, IL-4, IL-10, IFN-gamma, and TNF-alpha mRNA. The mRNAs of these cytokines could also be detected at the single cell level; as they were produced in a high percentage of germinal centre T cells, whereas immunohistological staining was negative, we conclude that a high percentage of germinal centre T lymphocytes produce IL-2, IL-4, IL-10, IFN-gamma, and TNF-alpha in low concentrations in contrast to T cells outside the germinal centre, in which strong cytokine production in few cells was shown earlier.

B-Lymphocytes↗

CD26 expression in leprosy and other granulomatous diseases correlates with the production of interferon-gamma.

BACKGROUND: Leprosy represents a spectrum of clinical manifestations that reflect the immune response to antigens of Mycobacterium leprae. The tuberculoid form of leprosy, which is characterized by an organized development of granulomas, has recently been correlated with a Th1-like immune response. The lepromatous form of leprosy, with a characteristic lack of cellular immunity, has been correlated with a Th2-like immune response to mycobacterial antigens. Dipeptidylpeptidase IV (CD26) is an ectopeptidase that is expressed in various tissues; in the hemopoietic system, it is predominantly expressed by T cells. EXPERIMENTAL DESIGN: We stained frozen sections of skin biopsies obtained from patients with different forms of leprosy, sarcoidosis, and Piringer's lymphadenitis. Sections were stained for interferon-gamma (IFN-gamma) and CD26 with the alkaline phosphatase anti-alkaline phosphatase technique and in two-color stainings by immunofluorescence. RESULTS: We found strong signals for IFN-gamma and for CD26 in all investigated cases of tuberculoid leprosy. In contrast, in all biopsies taken from patients with lepromatous leprosy, we found no or very weak signals for these antigens. By immunofluorescence double-labeling, we could show that IFN-gamma and CD26 were expressed by the identical cell population. We confirmed this correlation of CD26 expression and IFN-gamma production in other granulomatous inflammatory reactions such as sarcoidosis and Piringer's lymphadenitis. CONCLUSIONS: From our results, we conclude that a high expression of CD26 may be suggestive of Th1-like immune reactions.

Dipeptidyl Peptidase 4↗