Monoclonal antibodies against human recombinant tumor necrosis factor: prevention of endotoxic shock

Six murine monoclonal antibodies, AT-1, 2, 3, 4, 5, and 6 were produced against human recombinant tumor necrosis factor (gamma TNF). AT-1, -2, -3, -4, and -6 were IgG1, and AT-5 was IgG2a. AT-1, -2, and -3 neutralized the activity of gamma TNF (2 X 10(3) U/ml) over a range of dilutions between 5 and 500 micrograms/ml of IgG, while AT-4, -5 and -6 failed to neutralize the activity in these concentrations. All the antibodies showed immunoprecipitating activity for gamma TNF (2 X 10(3) U/ml) over a range of dilutions between 0.5 and 500 micrograms/ml. The AT-6 was weaker than the rest. AT-1, which neutralized gamma TNF activity efficiently, and AT-4, which did not neutralize the activity, were used to protect mice against endotoxic shock. AT-1 protected mice from the lethal effects of endotoxin, while AT-4 failed to do so. AT-1, -2, and -3 also neutralized the activity of human and mouse natural TNF. AT-1, -2, and -3 neutralized the activity of gamma TNF, but not that of lymphotoxin (LT) and interferon (IFN).

Isolation, amino acid sequence, synthesis, and biological activity of some oligopeptides from porcine spinal cord

Four oligopeptides, designated SCP-3, SCP-4, SCP-5, and SCP-6, have been isolated and purified to homogeneity from porcine spinal cord. The amino acid sequences have been determined as pyroGlu-Gly, pyroGlu-Gly-Gly, Met-Met-Gly, and Asp-Ala-Gly-Ala-Gly, respectively. All of these peptides have been synthesized by conventional liquid-phase or solid-phase methods. The synthetic and extracted peptides showed identical behavior in a reverse-phase high-performance liquid chromatography system. SCP-3 and SCP-4 exhibited some significant inhibitory activity on the electrical stimulation-induced contractions of longitudinal muscle strip of guinea pig ileum, and SCP-5 showed some stimulating effect on the same preparation. The physiological significance of these purified peptides is being investigated.

The antilipemic effectiveness of pentaerythritol tetranicotinate on hyperlipidemic patients with or without diabetes mellitus--a double-blind, randomized and two-period change-over experiment

Pentaerythritol tetranicotinate (Perycit), at an oral dosage of 750 mg daily, was given to 12 patients with idiopathic hyperlipidemia and to 12 patients with hyperlipidemia superimposed with diabetes mellitus (DM). With 2 months off-drug period as the baseline, each patient then received 3 months of placebo and 3 months of Perycit. The sequence of treatment was randomized and balanced in frequency. Blood glycosylated hemoglobin (Hb A1) and fasting plasma glucose (FPG) were used as indices of diabetic control. Serum triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), and TC/HDL-C ratio were measured and calculated in order to compare the antilipemic effectiveness of Perycit with that of placebo. The non-parametric Wilcoxon test was used for the statistical analysis. The results showed that in the idiopathic group, Perycit significantly lowered the serum level of TG and the ratio of TC/HDL-C, and elevated the serum level of HDL-C. In the diabetic group, although there was a similar improvement in diabetic control in both periods of placebo and Perycit treatments, there was no change in the serum levels of TG and HDL-C. There was a slight increase of the serum levels of TC in the periods of Perycit treatment, whereas a small increase of HDL-C resulted in a mild decrease of the TC/HDL-C ratio. There was mild and transient facial flushing during the Perycit treatment in 6 out of 12 diabetic patients. Otherwise, there was no side effects in either group. Pooling the two groups' data together, Perycit increased the serum levels of HDL-C and decreased the TC/HDL-C ratio. It is concluded that Perycit has antilipemic effects in patients with idiopathic hyperlipidemia, and may be helpful in reducing the atherogenic risks in these patients. In patients with hyperlipidemia superimposed with DM, although the serum lipids composition was not significantly changed after Perycit, the atherogenic risks might also be reduced as demonstrated by the decrease of the TC/HDL-C ratio.

Isolation and partial characterization of two biologically active peptides from porcine spinal cord

Two biologically active peptides designated SCP-1 and SCP-2 have been isolated and partially characterized from porcine spinal cord. The results of amino acid analysis, electrophoresis, isoelectric focusing and the chromatographic analysis of the dansylated derivatives indicate that these two peptides are homogeneous. The amino acid composition and apparent untriakontapeptide and SCP-2 is a pentacospeptide. The N-terminal amino acids of SCP-1 and SCP-2 are Arginine and Tryptophan respectively. SCP-1 can stimulate the contraction of isolated guinea pig ileum and SCP-2 induces hypotension in anesthetized rat. Both SCP-1 and SCP-2 show no morphine-like activity. The chemical composition and biological properties of SCP-1 and SCP-2 distinguish them from any known peptide.

Fatal primary Epstein-Barr virus infection masquerading as histiocytic medullary reticulosis in young children in Taiwan

We reported 3 fatal cases of primary Epstein-Barr virus (EBV) infection resembling histiocytic medullary reticulosis (HMR) in young children in Taiwan, where an HMR-like illness has been previously found to be prevalent. The disease ran a fulminant course, manifesting as fever, anemia, jaundice, skin rash, pulmonary infiltration, and/or hepatosplenomegaly lasting for only 1-3 weeks. Laboratory tests revealed no hemolytic anemia and Coombs test was negative. Sepsis or HMR was the main clinical differential. At autopsy, the spleen, liver, lymph node, lung, and bone marrow showed infiltration of atypical "histiocytes" or blasts, lymphocytes, and mature histiocytes with hemophagocytosis. Immunophenotype and gene rearrangement studies of the lymphoid tissues revealed that these atypical "histiocytes" were actually polyclonal B immunoblasts in one case and transformed T lymphocytes in the remaining 2 cases, representing two different types of virus-host interaction. Southern blot and in situ hybridization studies on frozen lymphoid tissues demonstrated the presence of EBV DNA in all 3 patients; the study for cytomegalovirus was negative. The young age of these patients, closely correlated with the prevalent age of primary EBV infection in the general populations in Taiwan, strongly suggest that these childhood cases of previously diagnosed HMR-like disease may actually represent a lethal form of primary EBV infection or fatal infectious mononucleosis.