A column chromatographic method for the combined analysis of creatine kinase-MB (CPK-MB) and lactate dehydrogenase 1,2 (LDH 1,2) isoenzymes.

A column chromatographic method for the simultaneous single-eluate isolation of CPK-MB and LDH 1,2 has been evaluated. The method is rapid in that the entire isolation is completed in less than an hour and subsequent analysis can be performed using presently available spectrophotometric methods and reagents without the need for electrophoresis equipment. In addition, since the isoenzymes are directly isolated, quantitation of enzymatic activity can be performed with precision. This technic permits detection of CPK-MB and LDH 1,2 in samples with normal values of total CPK and LDH utilizing a routine laboratory spectrophotometer. The sensitivities for diagnosis of acute myocardial infarction are 95% for LDH 1,2 and 100% for CPK-MB. The specificities for diagnosis of acute myocardial infarction are 86% for LDH 1,2 and 96% for CPK-MB.

Migration inhibitory factor and interferon in the circulation of mice with delayed hypersensitivity.

When mice infected with Mycobacterium tuberculosis strain BCG were inoculated intravenously with old tuberculin (OT) or living BCG cells, both migration inhibitory factor (MIF) and interferon appeared in the circulation within a few hours. In such animals, which showed delayed hypersensitivity by footpad tests, as little as 1.5 mg of OT or as few as 1.7 x 10(6) bacteria per mouse were capable of eliciting circulating MIF and interferon. Uninfected animals inoculated with large doses of OT or living BCG cells did not produce MIF or interferon. When nonspecific stimuli such as bacterial lipopolysaccharide (LPS; from Salmonella typhimurium strain LT-2), heat-killed Brucella abortus, Newcastle disease virus (NDV), and polyinosinic acid:polycytidilic acid (poly I:C) were inoculated intravenously into BCG-infected mice, MIF was produced in the circulation of animals challenged with LPS or Brucella but not in those challenged with NDV or poly I:C, although all the stimuli were capable of eliciting an interferon response. The interferon elicited in BCG-infected mice by specific antigen differed in at least one important property from the viral inhibitor produced by the nonspecific stimuli. The interferon which appeared after injection of OT or living BCG cells was destroyed by treatment at pH 2 for 24 hr at 4C, whereas the interferons produced after injection of the nonspecific stimuli were stable under the same conditions. The MIF activity in plasma from sensitized mice inoculated with specific antigen was also destroyed by treatment at pH 2. When mouse plasma containing both MIF and interferon activity was filtered through Sephadex G-100, both mediators were excluded in the same peak fractions. Sensitization of mice with complete Freund adjuvant instead of infection with BCG cells produces a different pattern of response. Although hypersensitive to specific antigen by footpad swelling tests, mice sensitized with complete Freund adjuvant failed to produce MIF or interferon when they were inoculated intravenously with OT or living BCG cells.