An indirect fluorescent antibody (IFA) test for the serodiagnosis of Kala-Azar.

The IFA test developed using Leishmania donovani promastigote and amastigote antigens showed very high antibody titre in clinically and parasitologically established cases (30) of kala-azar, the geometrical mean reciprocal titre (GMRT) being 870 +/- 5.4 and 5370 +/- 1.80 respectively with the two antigens. In contrast, the GMRT of normal subjects of endemic area was only 12.44 +/- 6.19 and 80.35 +/- 1.66 respectively with these antigens. None of the subjects from non-endemic area suffering with other parasitic diseases, such as malaria, filaria, amoebiasis, leprosy or tuberculosis (20 cases each) gave a positive response to any of the antigen. The test holds promise in the diagnosis of Kala-azar.

Adjuvant activity of some nonpyrogenic hydrophobic analogues of muramyl dipeptide in enhancing the primary humoral and cell mediated immune responses in guinea pig model.

Five muramyl dipeptide analogues synthesized by derivatization of gamma-carboxyl of D-isoglutamine residue of MDP into alkyl amides or incorporation of lysine residue at the site via epsilon-NH2 function were evaluated for immuno-adjuvant activity. Derivatization of gamma-carboxyl of D-isoglutamine into butyl, octyl and dibutyl residues stimulated delayed type of hypersensitivity (DTH) response, the maximum stimulation being observed with octyl amide. Introduction of lauryl amide residue abolished DTH response. The antibody response was impaired with all the alkyl amide analogues except for the lysyl amide derivative with which the response was higher than MDP. Correlation was observed between DTH response and macrophage migration.

Adaptogenic activity of Indian Panax pseudoginseng.

The crude extract and saponins of Indian pseudoginseng and saponins of Korean ginseng have been studied using a battery of biological tests in rats and mice. Indian pseudoginseng saponins were found to exhibit better activity than the Korean ginseng saponins in several tests employed. The results indicate a need for in-depth study of Indian pseudoginseng as an adaptogenic agent, after cultivation of the plant under controlled conditions.

Animal model for testing human Ascaris allergens.

Guinea pigs immunized through the nasal route by an antigenic preparation of human Ascaris lumbricoides produced predominantly homocytotropic antibodies. The sensitization of the homologous skin required a latency period. Hypersensitivity reaction was triggered within 30 min. of the antigen challenge. The antibodies were sensitive to heat and β–mercaptoethanol treatments and appeared to be similar to the IgE type of immunoglobulins of man and rabbit. The antigenic preparation elicited an immediate type of skin hypersensitivity reaction also in human subjects harbouring the Ascaris parasite. The guinea pig model appears suitable for testing the activity of Ascaris allergens.