Host protective immunity and vaccine development studies in lymphatic filariasis

Lymphatic filariasis caused mainly by infection fromWuchereria bancrofti andBrugia malayi remains as the major cause of clinical morbidity in tropical and subtropical countries. Development of vaccine against filarial infection can act as additional measure to the existing therapeutic and vector control methods in the control of this disease. The main hurdles in the development of anti-filarial vaccine are the strict primate specificity ofWuchereria bancrofti, the paucity of parasite material, the diversity of clinical manifestations and their associated complex immune responses, lack of clear understanding on host-parasite interactions and the mechanisms involved in protective immunity. However in the past few years, the information generated in immuno-epidemiological studies, correlated with observations in experimental animals suggests that a filarial vaccine is feasible. Initially live irradiated infective larvae have been successfully used to induce high level of protective immunity in several animal models. Applying diverse strategies, variety of purified or recombinant filarial antigens have been explored for their ability to induce protection in different host-parasite systems. Some of these targeted filarial antigens induced high level of resistance in experimental animals against challenge infections. More focussed studies on thorough characterization of parasitological and immunological changes associated with resistance induced by such candidate protective antigens and on delivery mechanisms and safety aspects will be crucial in their selection for possible use in humans.     

Nychthemeral rhythmicity of urinary copper levels in healthy Indians and renal stone formers

Nychthemeral rhythmicity of urinary copper (Cu) was studied in 40 clinically healthy volunteers and 35 renal stone formers. A marked diurnal rhythm was noticed in urinary Cu levels in healthy subjects with maximum excretion at 0000 to 0600 hr followed by a progressive fall during the rest of the period reaching minimum between 1200 to 1800 hr in males and 0600 to 1200 hr in female volunteers. Similarly, all stone patients exhibited a definite rhythm in urinary Cu with significant amplitude and acrophases at 2145 hr for males and 2141 hr for female stone formers. However, there was no difference in mean 24-hr Cu excretion in male and female stone formers, whereas a significant change was observed in case of healthy subjects. Urinary Cu was found to be significantly increased in renal stone formers in comparison to healthy controls of either sex attributing a significant role of this overlooked trace mineral in the crystallization and/or activation of either of the process of stone formation in the renal tubules.     

Biochemical markers of liver and kidney function are influenced by thyroid function-a case-controlled follow up study in Indian hypothyroid subjects

Thyroid hormones regulate the renal hemodynamics and basal metabolic rate of most cells. This hospital-based case-control study was done to evaluate the changes in biochemical markers of liver and kidney function in hypothyroid subjects before and after treatment. The study included 176 subjects randomly selected from Thyroid clinics. Serum T₃, T₄, TSH, Liver and Kidney Function tests were analysed using standard kits. Forty-six hypothyroid patients were re-evaluated 6 weeks after thyroxine substitution therapy. Hypothyroid subjects (n=80) showed significantly raised serum creatinine and uric acid levels as compared to euthyroid subjects (n=96). After 6 weeks of thyroxine replacement, serum creatinine and uric acid decreased significantly and were comparable to euthyroid group. A positive correlation of ALT, AST, uric acid, protein and albumin with TSH levels (p<0.05) and negative correlation of serum T₄ levels with ALT, AST, proteins (p<0.05) was observed in the hypothyroid group. Hypothyroidism results in reversible impairment of hepatorenal function.