Antibody response to Syphacia obvelata infection was observed in AKR/J mice by ELISA. Experimental infection with the pinworm eggs showed the presence of specific IgG against S. obvelata somatic antigens at 12 days postinfection, and that it increased steadily thereafter. Sera of S. obvelata-infected mice showed cross-reactivity with somatic antigens of other Syphacia species such as S. mesocriceti and S. muris, but not with Aspiculuris asiatica. Western blotting of S. obvelata antigen with sera of S. obvelata-infected mice showed a corresponding increase in the number of bands during the course of infection. Infected mice showed significantly higher antibody production to sheep red blood cells than the uninfected control mice. Thus, S. obvelata infection is shown to alter the humoral response to nonparasitic antigenic stimuli. These observations indicate that infection by helminths, which apparently do not produce clinical symptoms, might modulate the immune system of the host and, therefore, affect experimental results.

An overview of the epidemiological, biological, and clinical studies of Taenia and taeniasis in Taiwan for the past century is presented. The phenomenal observations that led to the discovery of Taenia asiatica as a new species, which differ from Taenia solium and Taenia saginata, are described. Parasitological surveys of the aborigines in Taiwan revealed a high prevalence of taeniasis, which might be due to the culture of eating raw liver of hunted wild boars. Chemotherapeutic deworming trials involving many patients with taeniasis were discussed. Praziquantel was found to be very effective, but sometimes complete worms could not be recovered from the feces after treatment, probably due to the dissolution of the proglottids. Atabrine, despite some side effects, can still be used, in properly controlled dosages, as the drug of choice for human T. asiatica infection if we need to recover the expelled worms for morphological examinations. Research results on the infection of T. asiatica eggs from Taiwan aborigines in experimental animals were also noted. Since the pig serve as the natural intermediate host of T. asiatica and the predilection site is the liver, a differential comparison of other parasitic pathogens that might cause apparently similar lesions is also presented.

Deletion of the long arm of chromosome 20 (del 20q) has been observed in patients with myelodysplastic syndrome (MDS) or myeloid malignancies. We experienced an MDS female case of del 20q accompanied by clusters of plasmacytic cells in bone marrow. Her bone marrow cells showed morphological abnormalities in three lineages and the chromosomal abnormality of 46, XX, del (20) (q11.2q13.3). Although the percentage of plasma cells was low in free cells, such cells showed nuclear abnormalities. In bone marrow clots, we also observed clusters of anti-CD38 and anti-CD138 antibody-positive cells. According to the FAB or WHO classification, the diagnosis was unclear. Therefore, we were obliged to term this case as MDS with plasma cell dysplasia. This patient was considered to be a rare case of MDS related to abnormalities in myeloid and B-lymphoid cells.

Dynamics of serum liver enzymes in rabbits experimentally infected with metacercariae of Fasciola sp. (intermediate form between Fasciola hepatica and F. gigantica) were monitored. Gradual increase of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were observed from 3 weeks post-inoculation (WPI) and peaked at 6 WPI, which corresponded well to the period of migration and development of juvenile fluke in the liver parenchyma and the time when the young adult flukes migrated to the bile duct. However, no significant increase in serum gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP) were observed. This could reflect reduced or minimal injury of bile ducts and biliary epithelia as the flukes had reached the adult stage. Alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) were not detected in the infected rabbit during the course of the experiment. Serum liver enzymes monitoring might be useful for understanding the host-parasite relationship in fascioliasis.