Monitoring of immune response by blood serum profiling using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

The application of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) to the analysis of blood serum leads to the observation of a large variety of reproducible mass spectral peaks corresponding to blood components. In this study, the use of MALDI-TOFMS was developed as a tool for monitoring immune response to bacterial infection. Employing the MALDI-TOFMS approach, the levels of many components of blood were found to be immune response independent whereas others were found to correlate directly with the response of the immune system to two known types of bacteria (Staphylococcus aureus and Enterococcus faecalis). The methodologies reported here should be useful for the rapid monitoring of blood, especially that of the immune response mechanisms in various animal species.

Rapid identification and speciation of Haemophilus bacteria by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Several species of the genus Haemophilus are well known etiological agents of pneumonia, meningitis, conjunctivitis, epiglottitis and chancroid. However, identification and speciation of Haemophilus is both time consuming and labor intensive. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOF-MS) has been used by several investigators to profile proteins from intact and disrupted bacteria; consequently, MALDI/TOF-MS has emerged as a powerful tool in diagnostic bacteriology. This paper reports the use of MALDI/TOF-MS as a technique for the rapid identification and speciation of Haemophilus. This technique was used to not only identify the pathogen, H. ducreyi, but also to determine strain differences from different isolates. Mass spectral 'fingerprints' were obtained which permitted the rapid speciation of not only pathogenic forms of Haemophilus, but also those bacteria which are normally regarded as non-pathogenic and members of the normal flora. MALDI/TOF mass spectra can be acquired in 10 min, allowing the identification of Haemophilus spp. within 24 h rather than the 48 h or more needed for traditional bacteriological methods. In addition, these are the first mass spectral fingerprints available in the literature for many of these organisms.

Analysis of rabbit tear fluid using capillary electrophoresis with UV or laser-induced fluorescence detection.

In preliminary studies of the development of tear analysis methodology that may eventually be useful in the clinical setting, the authors evaluated various protocols for analyzing rabbit tears by capillary zone electrophoresis (CZE). Conditions included the use of a 50-mM monosodium phosphate buffer, pH 2.5, or a 400-mM sodium borate buffer, pH 8.9, both with ultraviolet (UV) detection, as well as a 50-mM borate buffer, pH 8.5, with laser-induced fluorescence (LIF) detection of ATTO-TAG CBQ (Molecular Probes, Inc., Eugene, OR, U.S.A.) derivatized tears. All CZE analyses were performed with a P/ACE System 2100 instrument equipped with System Gold software (Beckman Instruments, Fullerton, CA, U.S.A.), using a 50 microns x 57 cm (50 cm to the window) fused-silica capillary, at 25 degrees C, with constant voltage of 20 kV for UV detection and 11 kV for LIF detection. Tear samples were collected from normal rabbit eyes by means of 10-microL glass micropipets. The volume of each sample was approximately 2 microL. Analysis using the phosphate buffer with UV detection produced as many as 35 peaks in each sample, of which 11 peaks were readily discerned. This compared favorably with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, which produced 32 bands with silver staining and 11 quantifiable bands with Coomassie brilliant blue staining. Many of the tear protein components have yet to be identified. CZE analysis with the high-ionic-strength borate buffer with UV detection produced only four peaks, and the low-ionic-strength borate buffer with LIF detection produced only six peaks. CZE analysis was completed in less than 1 hr, compared with 7-8 hr for SDS-PAGE. In summary, CZE analysis of tear fluid is comparable to CZE analysis of other bodily fluids and shows great potential for use in clinical diagnosis as well as for enhancing our understanding of the cellular actions of tears on the front of the eye.