【摘要】 <正> 血吸虫病的病变和发病机理是由于虫卵在人体组织中引起肉芽肿所致。目前认为发育成熟含毛蚴的血吸虫卵分泌可溶性抗原物质,它致敏寄主后,使淋巴细胞、巨噬细胞和嗜酸粒细胞集聚在虫卵周围形成了肉芽肿,并证明血吸虫卵肉芽肿是属于迟发型超敏免疫反应(Warren,1972)。Warren等(1975)还认为日本血吸虫卵和曼氏血吸虫卵肉芽肿形成的有关免疫因素及发病机理可能有所不同。通过组织化学的途径对组织内日本血吸虫卵胚胎发育的研究,不仅有助于探讨血吸虫卵发育的生理及寄主组织和虫卵之间的相互关系,而且对血吸虫病的病原诊断方面亦有一定的实际意义。为此,作者对沉积于组织内的虫卵从受精卵细胞至形成毛蚴的胚胎发育全过程进行了一般组织学及组织化学的观察。更多还原

【Abstract】 This paper deals with the results of histologieal and histochemieal investigation on the embryonic development of the ova of Schistosoma japonicum deposited in the tissues of mice and rabbits. A variety of wellestablished histochemieal techniques are used to analyze the nature of the in vivo eireumoval precipitates, usually referred to as Hoeppli phenomenon in literature.The duration of differentiation and development from a single fertilized ovum to a cilliated miracidium in host tissue requires 11 to 12 days. Based on the structural characteristics, the entire course of development may be divided into four stages: (1) single-cell stage, (2) cell-cleavage stage, (3) organo-formation stage, and (4) mature-miracidium stage. The characteristic features of each stage are described as follows.In the single-cell stage, a great deal of lipids are found in the vitelline cells with a small amount of nucleic acids and proteins, while polysaecharide deposits are very-scanty. Thereafter in cell-cleavage and organo-formation stages, both nucleic acids and proteins are markedly increased during the cell division, and the reaction for polysaccharides soon becomes positive in the area between the embryo and the eggshell, although the embryo itself is devoid of polysaecharide. At these stages the amount of lipids decreases gradually. In the mature-miracidium stage, nucleic acids are most pronounced in the cells of neural mass which occupies the center of the mature embryo, and in the germinal cells. Most interesting of all, the lipids richly stored in the early single-cell stage have almost disappeared or are present only in the form of few granules scattered around the miraeidium. However, large quantities of carbohydrates are found in the whole miraeidium at this stage. It seems that in the schistosomal embryo some enzymes may be existent for the conversion of lipids to carbohydrates during embryogenesis. Phosphatase activity is also extensively distributed in the embryo during development. No evidence of inorganic substances such as calcium or iron could be demonstrated during the embryonation.The results of histochemieal observations on the egg-shell-enclosed miraeidium indicate that the apical gland contains mainly diastase-fast PAS-positive material, while the pair of cephalic glands shows, besides a lot of neutral mucopolysac-charides, positive reactions for ENA, proteins and phosphatase. It is therefore suggested that there is a suite of complex chemical components consisting of neutral mucopolysaccharides, proteins and enzymes in the cephalic glands of the miraeidium.Once the miraeidium have been formed, the secretions of both apical and cephalic glands of miraeidium ooze out of the egg-shell, meanwhile the latter, for the first time, takes on a very strong diastase-fast PAS-positive reaction. In tissue sections of infected mice, the in vivo precipitates appear around intact ovum with nature miracidium as early as 41 days after infection. They are excrescences of a thick layer of eosinophilic fringes on the shell surface. As the in vivo circumoval precipitates mainly occur around mature ova, the presence of antigen component is apparently related to the time of miracidial maturity. It is conceivable that the in vivo circumoval precipitates represent an antigen-antibody complex. Our observation also indicates that the in vivo circumoval precipitates show prominent zonation: the inner zone consists a corona of teeth, perpendicularly and fan-likely radiating from the egg-shell, while the outer zone is usually a homogeneous and doughy substance circumscribing and interposing the inner corona. Histochemical observation reveals that the components of the in vivo circumoval precipitates contain mainly diastase-fast PAS-positive substances, basic proteins and proteins combined with tyrosine, trytophan and histidine. A schematic representation of ova with miracidium of S. japonicum and the in vivo circumoval precipitates is hereby precented.更多还原