Elevation of serum transcobalamin II in patients with scrub typhus.

Serum transcobalamin II levels were measured in scrub typhus patients. Eighteen out of fifty-two patients admitted to Maharat Nakhon Ratchasima Hospital were diagnosed with scrub typhus infection. The serum unsaturated vitamin B12 binding protein (UBBC) and total vitamin B12 binding protein (TBBC) levels in these patients were significantly higher than in normal subjects (p < 0.001). The mean serum transcobalamin II level in the typhus patients was also significantly higher than in the normal subjects (p=0.004). There was a significant correlation between serum TCII levels and typhus IgM or IgG titers (p < 0.05), but not to total IgM levels. These findings indicate that patients with scrub typhus had stimulation of the recticuloendothelial system as a result of a considerable increase in transcobalamin II levels.

In vivo and in vitro measurement of cell mediated immunity in Marek's disease: role of reticuloendothelial system.

Dinitrofluorobenzene (DNFB) contact-sensitivity test and leucocyte adherence inhibition (LAI) test were performed in this study as in vivo and in vitro tests to measure the cell-mediated immunity (CMI) in chickens subjected to stimulation of reticuloendothelial (RE) system, depletion of RE system and other experimental groups after being challenged with Marek's disease (MD) virus. It was found that CMI was lower in the birds with depleted RE system and infected control birds, whereas CMI was higher in the birds with activated RE system and vaccinated birds as revealed by DNFB contact-sensitivity test. In cases of LAI test, the number of LAI-positive birds were highest in the chicks with depleted RE system particularly in 3rd and 4th month of age, when the incidence of MD was also maximum.

Effects of Anti-salivary Gland Antibodies on Circulating and Tissue Lymphocytes: An Animal Experimental Study

In the present study, normal guinea pigs were used to investigate the possible pathogenic role of cell-mediated immunity in Sjogren's syndrome. The effects of anti-salivary gland antibodies on circulating lymphocytes, various organs including salivary glands, thymus and the reticuloendothelial system, and on delayed hypersensitivity were studied. Our study demonstrated that anti-salivary gland antibodies directly affected circulating lymphocytes. There was a 60-80% decrease in the lymphocyte count from the original level with a maximum effect at 5 hours after the introduction of the antibodies. When antibodies were injected repeatedly, the recovery to the pre-injection level of lymphocytes was delayed. We also found that antisalivary g1and antibodies were not organ-specific and were cross-reactive with various organs that are often involved in Sjogren's syndrome. Direct immunofluorescent study showed antibody deposits in the thymus-dependent areas of lymph nodes. These results suggest that antisalivary gland antibodies are lymphocytotoxic and have an anti-T cell property. The anti-salivary gland antibodies prepared in this experiment did not produce any pathological lesions such as those found in Sjogren's syndrome. The amount of antiserum or the period of administration might not have been long enough to produce pathological changes. Another possibility is that the anti-salivary gland antibodies might be species-specific. On the basis of these results, it appears that impaired cell-mediated immunity is not the primary pathogenic factor responsible for Sjogern's syndrome but rather that deranged immunity is secondary to the development of anti-salivary gland antibodies which occur in Sjogern's syndrome.