A quantitative immunological study of plasma proteins in blood stains

An electroimmunodiffusion technique, which enables precise measurements of the concentrations of some plasma proteins in blood stain extracts to be made, has been developed. It is possible that if a number of plasma proteins, with high discriminating power were found to be stable in blood stains, and were measured by this technique, that the information so obtained could be of value for the forensic examination of blood stains. The tandem antigen–antibody crossed electrophoretic technique has also been examined, and its application to this problem assessed. Nine plasma proteins have been examined, and some of them found to be stable in blood stains. Additional immunological techniques l1ave been employed in an attempt to establish the nature of the changes which the unstable proteins underwent. Seven of the proteins were quantitated in samples provided in a number of blind trials, in order to test the feasibility of a plasma profiling system for matching blood stains. Finally, the advantages and disadvantages of a plasma profiling system over existing methods of blood stain analysis have been discussed

Monoclonal antibodies produced against isoelectrically focused nocardia asteroides proteins and characterized by the immunoelectro-transfer blot technique, 1984

Nocardiosis is one of the most difficult bronchiopulmonary infection to diagnose because of its close morphological, physiological and antigenic resemblance as well as its coexistence with other bacteria which cause chronic pulmonary diseases, especially Mycobacterium tuberculosis. The objective of this work is to apply improved techniques to the delineation of the antigenic specificity of Nocardia asteroides which may provide early diagnosis to detect specific antibodies in the sera of nocardiosis patients. Nocardia asteroides B1042 was grown in modified Sauton's medium in liquid shake culture at 35C for 4 and 6 weeks. Culture filtrates (CF) and homogenates (H) were prepared and concentrated. The protein content of the CF and H was estimated. Rabbits were immunized with the CF and H antigens in incomplete Freund Adjuvant. These antigens were analyzed by Immunoelectrophoresis (IEP), isoelectric focusing (IEF) and an immunoelectro-transfer blot technique modified for use with pH gradient polyacrylamide gels. Rabbit antisera to the CF and H antigens demonstrated consistency in antibody production with the maximum number of precipitin arcs observed after 8 to 12 weeks of immunization. The isofocused patterns of the CF and H proteins were similar with only quantitative differences in the respective components. An exception was that one band at 3.5 pH was present in the CF, but not in the H antigenic complex. Each pattern revealed at least 20 protein components having isoelectric points (pis) in the range of pi 4.0 to 5.4. The modified immunoelectro-transfer blot technique was optimized and combined with the sensitivity afforded by enzyme immunoassay (EIA). These combined techniques showed that most of the proteins of the isofocused patterns reacted as antigens against rabbit antisera, and at least 8 of them also reacted with sera from nocardiosis and tuberculosis patients. A specific antigen with a pi 4.68 reacted with 47% of the sera from nocardiosis cases and not with those from tuberculosis patients. Three monoclonal antibodies (MAbs) directed against three of these anti-genic factors (1,6 and 8), located at pis 4.0, 4.43 and 4.68 respectively, were produced. Two of these MAbs showed specificity to Nocardia because they did not react with the typical Mycobacterium tuberculosis sonicated cell extract. The potential use of these MAbs will facilitate the further evaluation of specific IN. asteroides antigens and may even provide a rapid serological test for nocardiosis