Modulation of immunoglobulin production and cytokine mRNA expression in peripheral blood mononuclear cells by intravenous immunoglobulin

Intravenous immunoglobulin (IVIG) has the potential to regulate Ig production, but the mechanism(s) responsible for this effect is unknown. In experiments reported here, we examined the ability of IVIG to regulate Ig production in human peripheral blood mononuclear cells (PBMCs) stimulated with pokeweed mitogen (PWM). IVIG (2–10 mg/ml) showed a potent (80–85%) inhibition of PWM-stimulated IgG, IgM, and IgA production. To determine more precisely how IVIG mediated the inhibition of Ig production, we studied Ig promoting cytokine gene expression after PWM stimulation with or without IVIG (2 and 10 mg/ml) using dot-blot techniques. RNA was isolated from PBMCs at predetermined time points and probed with cDNAs specific for human cytokines (IL-1-, IL-2, IL-2R, IL-4, IL-5, IL-6, -IFN, and TNF-). IL-6 mRNA accumulation was maximal at 4.5 hr post-PWM stimulation and was inhibited 64–75% when IVIG (10 mg/ml) was present. -IFN mRNA levels peaked at 72 hr poststimulation and were also 68–75% inhibited by IVIG. IL-2 mRNA levels peaked at 4.5 hr and were 23–46% inhibited by IVIG. The inhibitory effect of IVIG on production of these cytokines (IL-6 and -IFN) was also observed at the protein level in sonicated PBMCs after incubation with PWM and IVIG. The mRNA levels for other cytokines were not or only minimally inhibited by IVIG. Addition of IL-6, -IFN, or IL-2 partially restored Ig production in IVIG-treated PWM-stimulated cultures, suggesting that inhibition of other cytokines or another mechanism(s) independent of cytokine inhibition might also be involved, although inhibition of IL-6, -IFN, and IL-2 may be one of the critical factors in the suppression of Ig production by IVIG.     

Haematological improvement by long-term administration of recombinant human granulocyte-colony stimulating factor and recombinant human erythropoietin in a patient with severe aplastic anaemia

A 6-year-old girl with post-hepatitic severe aplastic anaemia was referred to our hospital. Haematological examination showed a haemoglobin level of 5.2 g/dl, platelet count of 8,000/l, and white blood cell count of 130/l with 17% neutrophils. She was treated with recombinant human granulocytecolony stimulating factor (15 g/kg/day i.v.) and cyclosporin A (6 mg/kg/day p.o.). The absolute neutrophil count gradually increased, but Hb and platelets were not improved. The intravenous administration of recombinant human erythropoietin (100 U/kg three times a week) was started, and the reticulocyte count reached 20000/l on day 12. The platelets increased to 81000/l after 16 months of combined administration of recombinant human granulocyte-colony stimulating factor, recombinant human erythropoietin and cyclosporin A. After 20 months of combined administration, the haematological results were: Hb, 13.1 g/dl; platelets 80000/l: WBC, 9500/l with 40% neutrophils. After recombinant human granulocyte-colony stimulating factor treatment, the myeloid elements of the bone marrow and the number of granulocyte-macrophage colony forming units increased. Bone marrow erythropoiesis and erythroid colonies also increased after recombinant human erythropoietin administration. The clinical course suggested a beneficial effect of haemopoietic growth factors and cyclosporin A in post-hepatitic aplastic anaemia.     

Computational study on antioxidation mechanism of catechins

All C-H and O-H bond dissociation enthalpies (BDE's) in catechins, (-)-epigallocatechin) were calculated by semi-empirical molecular orbital calculation using the SPARTAN program. The BDE's of benzyl hydrogens (C-2 position in catechins) were found to be quite low. This suggests that abstraction of benzyl hydrogen is crucial step for antioxidative activity. This is corroborated by the reported results of LC/MS and spectrophotometric analysis of reaction intermediates from catechins treated with AAPH.     

A 13-week subchronic toxicity study of chitin in F344 rats

A subchronic toxicity study of chitin, a natural structural component of crustacean shells, was performed in F344 rats by feeding of the powdered diet containing 5%, 1.7%, 0.6%, 0.2%, and 0% concentrations of the substance. Each group consisted of 10 males and 10 females. All animals survived until the end of the experiment. There were no changes indicating obvious toxicity of chitin in the clinical signs, body weight, food intake, hematology, serum biochemistry, or histopathological findings, except a slight decrease in body weight gain in the 5% chitin-treated males. Although the mechanism is unclear, the suppression of body weight gain may be due to the slight decrease in caloric content of the food in the 5% chitin-treated animals, a change unrelated to toxicity. Thus, there was no obvious toxicity of chitin in F344 rats at concentrations up to 5% in the diet for 13 weeks.     

The effects of tensile load on the metabolism of cultured chondrocytes

The effect of cyclic tensile load on articular cartilage metabolism was investigated experimentally using 12 Japanese White rabbits. Chondrocytes obtained from the knee joints were cultured on plates with flexible silicone rubber bases. They were subjected to a cyclic (3 seconds on and 3 seconds off) tensile load for 24 hours with a maximum increase in area of 17%. Proteoglycan synthesis, collagen synthesis, and tissue inhibitors of metalloproteinases production by the chondrocytes under the load were quantified and compared with those produced by the control cells in an unloaded condition. The cultured chondrocytes under the cyclic tensile load perpendicularly aligned to the direction of the tensile load. Collagen synthesis and tissue inhibitors of metalloproteinases production increased significantly under the cyclic tensile load, although no significant change in proteoglycan synthesis was observed. These results suggested that the cyclic tensile load on the chondrocytes contribute to the regulation of articular cartilage metabolism in part.     

Changes in immune function following surgery for esophageal carcinoma.

Changes in immune function due to surgical injury have been well-documented. Immunosuppression is one of the causes of infectious complications leading to organ dysfunction in critical illness. It is not known what kind of surgery in the daily clinical practice causes immunosuppression. Stress response and immune function following surgery for esophageal carcinoma, assuming a highly-stressed operation, were studied and then compared with the stress response and immune function following gastric surgery, a moderately-stressed procedure. Forty patients who underwent esophagectomy and 39 patients receiving gastric operation were studied. The concentrations of serum interleukin-6 (IL-6) were measured preoperatively, at 1, 2, and 6 h, and at 1, 3, and 10 d after operation. Total protein, serum albumin, rapid turnover protein, serum CRP, and cortisol were measured before operation and at 1, 3, 7, and 21 d after operation. ConA- and PHA-stimulated lymphocyte proliferation, IgA, IgG, and IgM were also measured preoperatively, and on 7 and 21 d following surgery. The patients were fed exclusively by total parenteral nutrition (TPN). A striking rise of IL-6 was observed, with a peak in both groups at 1 to 6 h following operation. The peak values were 419+/-30 pg/mL, which was approximately twice as high in the esophagectomy patients as in the gastrectomy patients (195+/-40 pg/mL). CRP and cortisol also increased after operation, and these increases were also significantly greater in the esophagectomy patients. ConA- and PHA-stimulated lymphocyte proliferation decreased significantly 7 d after esophagectomy (P<0.05), but was unchanged in the patients receiving gastrectomy. Suppression of cellular immunity correlated significantly with serum cortisol, and was preceded by a rise in serum IL-6. The IgA, IgG, and IgM levels, however, remained unchanged from their preoperative values throughout the study in both groups. Nutritional status in terms of serum protein, albumin, and rapid turnover protein, decreased postoperatively, but there was no difference between the two groups. It is, therefore, concluded that cell-mediated immunosuppression, preceded by a hyperinflammatory response, is an observable reaction in patients following esophageal surgery, but not in patients undergoing gastric surgery.     

Clinicopathologic study of mass-screened neuroblastoma with special emphasis on untreated observed cases: a possible histologic clue to tumor regression

Spontaneous regression and maturation of neuroblastoma (NB) are well documented and occur frequently in infants, including those detected by mass screening. To seek histologic clues for regression/maturation in mass-screened NB, clinicopathologic features of 12 tumors that were resected after 2 to 18 months of untreated observation were reviewed. Unobserved screened and age-matched unscreened patients were also studied. To evaluate the possible important role of apoptosis, apoptotic cells were detected by in situ deoxyribonucleic acid (DNA) nick end labeling and immunohistochemical stain for activated caspase-3. Nests with a varying degree of reduced cellularity ("less cellular" and "hypocellular" nests) were common in patients younger than 18 months of age, and were rare in older patients. Two characteristic cells, which have not been focused previously, were frequent, especially in the hypocellular nests. One showed amorphic eosinophilic cytoplasm with pyknotic nuclei and the other contained plump cytoplasm with well-maintained nuclei. These cells were also observed in 89% of the unobserved screened NBs and 79% of the age-matched unscreened patients with good outcome, whereas they could not be confirmed in any of the age-matched unscreened NBs with poor outcome. The amorphic and plump cells were negative for activated caspase-3 and in situ DNA nick end labeling. From these results, the authors hypothesize that these cells most likely represent a degenerative process, in either a state before the activation of caspase-3 or a caspase-independent form of cell death. The presence of less cellular and hypocellular nests with amorphic/plump cells may serve as one of the important clues in predicting tumor prognosis.     

Treatment of Lethal Midline Granuloma Type Nasal T-Cell Lymphoma

Nasal T-cell lymphoma of the LMG type (LMG-NTL) is characterized by progressive, unrelenting ulceration, and necrosis of the nasal cavity and midline facial tissues. The clinical behavior of this tumor in 16 patients is compared with that of a nasal lymphoma of non-LMG-NTL type (non-LMG-NTL) in 8 patients and a paranasal sinus lymphoma (PSL) in 6 patients. All patients had stage I or II disease. Fourteen of the 16 patients with LMG-NTL received chemotherapy before and/or after radiotherapy. Cause-specific 5-year survival rates for patients with LMG-NTL, non-LMG-NTL, and PSL were 22%, 75%, and 67%, respectively. Seven patients with LMG-NTL, had complete response, although 3 recurred, whereas it was incomplete in 9 patients. The data indicates that it is desirable to deliver 50 Gy or more to achieve in-field control of LMG-NTL.