A study on assay method for fucose and sialic acid contents in sputum and serum of patients with lung diseases
Fujisawa, K.; Yasuoka, S.; Tatenuma, Y.; Noda, Y.; Nakanishi, Y.; Nii, Y.; Ozaki, T.; Ogura, T.
Nihon Kyobu Shikkan Gakkai Zasshi 26(6): 658-664
1988
ISSN/ISBN: 0301-1542 PMID: 3241505 Document Number: 324872
In order to establish suitable assay methods for fucose and sialic acid contents in sputum and serum, and to examine their diagnostic values in sputum and serum of patients with lung diseases, assays were performed by method I, a colorimetric method without isolation of these sugars and by method II involving isolation of these sugars using HPLC. In method I, the fucose content was measured by the method of Gibbons, a colorimetric method without isolation from other sugars. In method II, the fucose content was measured by a colorimetric method using 2-cyanoacetamide method after it was isolated from other sugars by HPLC using Aminex HPX-87. It was shown that fucose concentration measured by method I was about 3-fold higher in serum and 4-fold higher in purulent sputum than the value obtained by method II, while it was almost the same as the latter in mucoid sputum. This result indicates that method I is not suitable for assay for fucose content in serum or purulent sputum although it yields accurate measurement of fucose content in mucoid sputum. The sialic acid concentration value obtained by measurement with method I, the TBA method was almost the same as that by method II, in which the concentration was estimated by absorbance at 200 nm after isolation by HPLC, not only in mucoid sputum but also in serum and purulent sputum, indicating that the sialic acid concentration in these samples can be accurately measured by the TBA method, a conventional colorimetric method. It was shown by gel filtration and DEAE-Sephacel column chromatography that considerable amount fucose and sialic acid in serum are distributed to different proteins of glycoproteins from each other, and about 35% is distributed to IgG in serum of normal subjects. It was also shown that changes in serum fucose concentration are caused by those in the concentrations of both IgG and component other than IgG. It was suggested that the serum fucose level has a diagnostic value different from that of serum N-acetylneuraminic acid (NANA) level in patients with lung diseases. It was confirmed by method II that NANA content of purulent sputum is higher than that of mucoid sputum while there is no significant difference between the fucose content of mucoid and purulent sputum in patients with chronic airway diseases.