Lysozyme and the Pericapillary Reticulin Network

Abstract

We have previously observed a heterogeneity in the carbohydrate fraction of human reticulin fibres and basement membranes. This heterogeneity seemed to be related to the biological age of the subject, the age of the network, the metabolic characteristics of certain organs and tissues and the functional dynamics of various cellular groups^1,2. In a further investigation of the mechanisms of silver impregnation, which will be described in a later publication, we made many enzyme digestions (sialidase, lysozyme, pectinase, α-amylase, β-glucuronidase, bacterial and testicular hyaluronidase, ribonuclease, pepsin, trypsin, papain and collagenase). During this investigation a peculiarity was revealed after incubation with lysozyme of the samples fixed in Carnoy solution. In the sections treated for 48 h at 37° C with lysozyme (Worthington Biochemicals Corporation, twice crystallized 5 mg/30 ml. of 0.2 molar phosphate buffer, pH 5.3 (ref. 3)) there was a constant disruption and dislocation of the pericapillary (or perisinusoidal) reticulin network (Figs. 1–4). These aspects have not been seen in control slides incubated in an inactivated lysozyme by Lugol's iodine 1 : 300 buffer³ or in the buffer solution. Of all the glycoly-tic and proteolytic enzymes used, lysozyme alone could bring about this process. If the incubation with lysozyme was preceded by digestion with another enzyme, the changes occurred with the same intensity as those observed with lysozyme alone.