Analysis Lipoproteins

Total blood cholesterol less than 200 mg/dL HDL 35 mg/dL or more, repeat total cholesterol and HDL measurements within 5 years or with physical exam provide education on general population eating pattern, physical activity, and risk factor education. HDL less than 35 mg/dL, do lipoprotein analysis base further action on LDL levels. 

Perform fasting lipoprotein analysis and risk factor assessment. 

Christie, W.W. (1995) Silver ion high-performance liquid chromatography, in New Trends in Lipid and Lipoprotein Analysis (eds J.-L. Sebedio and E.G. Perkins), AOAC Press, Champaign, Illinois, USA, pp. 59-74. 

Understand the utility of (apo)lipoprotein analysis in clinical medicine, and understand the various types of primary lipoproteinemias. 

Three disorders of lipoprotein metabolism share these characteristics familial hypobetal-ipoproteinemia, chylomicron retention disease, and ABL (Table 27-2). The presence or absence of specific plasma apoB lipoproteins, as well as their mode of inheritance, can be useful when attempting to differentiate between these disorders. Symptoms associated with familial hypo-betalipoproteinemia are usually milder than for the other two and are inherited as dominant traits, that is, symptoms are observed in at least one parent of an affected offspring. Chylomicron retention disease is an autosomal recessive disorder with a severe phenotype commonly presenting soon after birth. Plasma lipoprotein analysis from affected individuals shows a specific absence of chylomicrons (apoB48) but normal amounts of VLDL and LDL (apoB 100). In our patient, evidence of recessive inheritance and absence of all apoB-containing lipoproteins implicates ABL as the most likely diagnosis. 

Ceriotti L, Shibata T, Fohner B, Weiller BH, Roberts MA, de Rooij NF, et al. Low density lipoprotein analysis in microchip capillary electrophoresis systems. Electrophoresis 2002 23 3615-22. 

Sebedia JL, Perkins EG. New trends in lipid and lipoproteins analysis. Champaign IL AOCS Press, 1995. 

Because of the elaborate calculations and data processing required for this kind of mathematical analysis, it has not been feasible to consider potentially useful techniques to accomplish this task manually. However, with the recent availability of high-speed digital computers of large storage capacity, and the development of data-handling techniques, such an extensive lipoprotein analysis becomes not only entirely realistic, but perhaps necessary in order to increase our understanding of the human lipoprotein system. 

It is our primary purpose here to emphasize some potentially important revisions in lipoprotein procedure, including additions to the technology of lipoprotein analysis. At the same time, we wish to present some recent data on lipoprotein composition determined by improved lipid analytical techniques. Finally, as a preliminary application of these techniques, we have included the evaluation of correlations between the major variables studied, including all measiued portions of the low- and high-density lipoprotein spectra as observed in an adult male and female population. 

One of the most important requirements for reproducible lipoprotein analysis is the accurate manipulation and monitoring of solvent densities. Since the lipoprotein fractionation utilized here involves the use of the monovalent salts NaCl and NaBr, the ability to control accurately and measure conveniently these salt-solution densities is essential. It is recommended, therefore, that both an absolute and relative method for density measurement, utilizing pycnometry (6) and precision refractometry (7, 8), respectively, be employed, A precision Abb sugar refractometer (Bausch and Lomb, Rochester, N.Y.), with a range of n from 1.203 to 1.508 operated above room temperature and temperature-controlled to 0.05°C, is extremely well suited for this latter work. 

Fig. 2. A stylized tracing of a low-density schlieren pattern showing the subdivision into 29 standard intervals, together with the corresponding (uncorrected) integral curve. The superimposed scale demonstrates the approximate magnitude of the F versus C effect for a typical lipoprotein analysis.

V. Potential Improvements in the Computer Methodology for Lipoprotein Analysis... 

Agarose gel chromatography has been used to separate the major lipoprotein classes for the characterization of serum lipoproteins (4,9,10). However, this technic for lipoprotein analysis has been limited because of the long experimental time, large sample required for analysis, low resolution and low reproducibility. 

Human sera used in this method are obtained from normal male and female subjects, hyperlipidemia and other patients with various diseases after 12-16 hours of fasting. Serum is usually used for lipoprotein analysis by this technique. Plasma can be also used for this method. However, it should be noted that plasma might form fibrin during HPLC procedures, so that serum is preferable to plasma for samples in this technique. Sera are stored at 4 C, and analyzed within one week. Sera stored at -20 C can be used for analysis. But, in the case of hyper-... 

Although the separation profile of the total lipoprotein fraction can be given by monitoring of protein moiety at A gg, the concentration of each lipoprotein class could not be calculated from peak area because of the difficulties in estimating lipoprotein levels caused by the following factors evaluation of turbidity, different molar coefficient of A2gg due to each lipoprotein, coelution of serum proteins with HDL fractions. At this point of view, a selective detection method of lipid components by enzymatic reaction using whole serum is useful for lipoprotein analysis as described in the next section. 

Reproducibility of our HPLC method for lipoprotein analysis is excellent. The elution volume Is reproducible within 0.01 ml for each lipoprotein peak in the case of the individual lipoproteins or serum lipid monitoring system. Reproducibility of the concentration of lipid in each lipoprotein class obtained as described in Section 5 is very high. The standard deviation from the mean value for each lipoprotein fraction was 0.1 to 0.4 mg/dl, and the coefficient of variation (Cv) is less than 2 % for the concentration of PL as presented in Table 3. 

However, this good correlation for the lipoprotein analysis between the two methods dose not exist when the size of lipoproteins no longer corresponds to the density as proved by a comparison of the results for a liver disease group (n=20) by Okazaki et al. (31), and by a study of lecithin cholesterol acyltrans-ferase deficiency by Kodama et al. (32). 

Our HPLC technique for serum lipoprotein analysis has many clinical applications, some of which have already been reported (32, 36-39). 

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