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H Hörig

Publications and source records attributed to H Hörig.

28 records · Page 2Linked to original sources

On the relative roles of interleukin-2 and interleukin-10 in the generation of lymphokine-activated killer cell activity.

Induction of cytokine gene transcription by recombinant human IL-2 (rhIL-2) in peripheral blood mononuclear cells (PBMC) from healthy donors was studied by qualitative polymerase chain reaction. In all donors tested, optimal doses of rhIL-2-induced transcription of genes encoding for IL-5, GM-CSF, IFN-gamma, and TNF-alpha whereas transcription of IL-1-alpha, IL-3, IL-4, and IL-6 genes could only be detected in about half of the donors. Moreover, we observed that different doses of rhIL-2 were needed to induce transcription of different cytokine genes. In contrast, transcription of IL-2 and IL-10 genes was only observed in a minority of donors, irrespective of the concentration of rhIL-2 used. Since IL-10 displays a well-characterized inhibitory activity on the synthesis of cytokines possibly involved in the generation of lymphokine-activated killer (LAK) cells, we asked whether the absence of IL-10 gene transcription plays a role in the induction of LAK cells. Thus, we tested the effects of different doses of rhIL-10 on the rhIL-2-driven generation of LAK activity. Interestingly, rhIL-10 dose-dependently inhibited the production of IFN-gamma and TNF-alpha induced by IL-2, but had no effects on PBMC proliferation and generation of LAK activity. Similarly, purified CD3-/CD16+ lymphocytes, the precursors of LAK effector cells, could be optimally induced by low doses of rhIL-2 to proliferate and generate MHC-unrestricted cytotoxic activity against NK-resistant targets in the presence of rhIL-10. Altogether, our results indicate that rhIL-2 induces transcription of a preferential pattern of cytokine genes, with the IL-10 gene being infrequently transcribed. On the other hand, rhIL-10 shows diverse effects on rhIL-2-triggered PBMC activation, in that it inhibits IFN-gamma and TNF-alpha production but does not affect PBMC proliferation or generation of LAK activity.

Base Sequence↗

[Artificial nutrition in surgery: status, current problems and perspectives].

Parenteral and enteral nutrition are safe and efficacious substitutes of normal oral intake even for prolonged periods of time and offer adequate treatment of protein-calorie malnutrition and effective palliation of cancer cachexia. Perioperative nutritional support reduces operative morbidity and mortality in malnourished patients. Furthermore, parenteral and enteral nutrition are an effective primary treatment for acute inflammatory bowel disease, short bowel syndrome and small bowel fistulae. Enteral nutrients specifically support structure and function of both the intestinal mucosa and the mucosa-associated lymphatic tissues: Recent clinical data emphasize the need to feed enterally whenever possible, especially in critically ill patients. Continuing efforts to include new substrates and to create more balanced and disease-adapted solutions of parenteral and enteral nutrition will improve the available systems. In addition, parenteral and enteral nutrition as a component of new complex treatment modalities including growth factors and cytokines will improve treatment and patient care in general surgery, oncology and traumatology.

Diet↗

Role of glutamine in the immune response in critical illness.

The dependence of human lymphocyte functions on the exogenous provision of glutamine (GLN) was evaluated in a series of in vitro experiments. The transcription of early activation markers (IL-2, IL-2-receptor, IL-4, IL-4, GM-CSF, IFN gamma) as evaluated by polymerase chain reaction was observed even in the absence of exogenous GLN. In contrast, later events of lymphocyte activation including cytokine production, proliferation of lymphocytes and lymphokine-activated killer cell activity were found to depend on exogenous GLN provision. These in vitro results are discussed in the context of established data on the reduction of peripheral blood GLN concentrations in critically ill patients and in view of recent studies reporting improved outcome of critically ill patients following GLN substitution. By and large, these data support the concept of GLN substitution in critical illness. However, the definition of indications and dose-response relationships clearly require further clinical studies.

Cells, Cultured↗

Glutamine peptide-supplemented long-term total parenteral nutrition: effects on intracellular and extracellular amino acid patterns, nitrogen economy, and tissue morphology in growing rats.

Glutamine (GLN) is a nonessential amino acid that is not included in current regimens for parenteral nutrition because of its chemical instability. This study tested the hypothesis that GLN supplementation during long-term total parenteral nutrition (TPN) (3 weeks) would enhance GLN availability, thereby improving nitrogen economy and growth in a growing rat model: Standard TPN delivering 300 kcal/kg per day (lipid:carbohydrate = 1.1) including 2.1 g of nitrogen per kilogram per day in an all-in-one solution was compared with an isonitrogenous, isocaloric, and isovolemic TPN regimen with 0.29 g of nitrogen per kilogram per day substituted by GLN derived from the dipeptides glycyl-GLN and alanyl-GLN (TPN GLN). Enterally fed controls were included. Analysis was confined to nonbacteremic animals with negative blood culture, in which extracellular and intracellular amino acid concentrations including GLN, nitrogen balance, serum protein concentrations, growth, and histologic sections of liver and small-bowel mucosa (light and scanning electron microscopy) were evaluated. Hepatic intracellular GLN concentrations were significantly lower, in animals receiving GLN-free TPN (11.7 +/- 1.6 nmol/mg fat-free dry and solid tissue mass, n = 9) compared with both GLN-supplemented TPN (16.0 +/- 3.0, n = 7) and enteral feeding (18.2 +/- 1.8, n = 6) (p < .001). Corresponding results were found for intracellular GLN concentrations in skeletal muscle (TPN standard 12.5 +/- 3.1, TPN GLN 14.7 +/- 3.1, enteral control 17.3 +/- 2.3, p < .05), intestinal mucosa, and spleen as well as for plasma concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗