DAVIES D A, CRUMPTON M J, MACPHERSON I A, HUTCHISON A M
Immunology. 1958 Apr;1(2):157-71.
Bacterial lipopolysaccharides and O' somatic antigens usually require treatment with alkali for maximal adsorption on erythrocytes in preparation for indirect haemagglutination. Although heating enhances sensitizing activity, owing partly to increasing dispersion, it is always less effective than alkali treatment. The presence of a protein component or of the chloroform soluble lipid A' does not inhibit erythrocyte sensitizing activity and no change in sugar constituents has been detected as a result of treatment. The specific polysaccharide of , which contains no lipid, requires alkali treatment for activity; in this case the effect of alkali is to remove -acetate (4 per cent). The loss of weight on treatment is also 4 per cent and no other differences can be detected by examining the infrared-absorption spectra of treated and untreated samples. For other materials investigated a loss of -acetyl has been detected, except where alkali treatment is not required to elicit maximal activity, e.g. the lipopolysaccharide which contains about 50 per cent of lipid `A'. By reacetylation of alkali treated polysaccharides it has been shown that -acetyl residues inhibit adsorption on to erythrocytes, but in some instances higher fatty acids are also removed to some extent by treatment with alkali.
细菌脂多糖和“O”体细胞抗原通常需要用碱处理，以便在制备间接血凝反应时最大程度地吸附在红细胞上。虽然加热可增强致敏活性，部分原因是分散度增加，但它总是不如碱处理有效。蛋白质成分或氯仿可溶性脂质“A”的存在并不抑制红细胞致敏活性，并且处理后未检测到糖成分的变化。不含脂质的[具体名称未给出]特异性多糖需要碱处理才能具有活性；在这种情况下，碱的作用是去除4%的乙酰基。处理后的重量损失也是4%，通过检查处理过和未处理过的样品的红外吸收光谱，未检测到其他差异。对于所研究的其他材料，已检测到乙酰基的损失，除非不需要碱处理来引发最大活性，例如含有约50%脂质“A”的[具体名称未给出]脂多糖。通过对碱处理过的多糖进行重新乙酰化，已表明乙酰基残基会抑制其吸附到红细胞上，但在某些情况下，较高脂肪酸也会在一定程度上被碱处理去除。
