Induction of immunity against experimental tuberculosis with mycobacterial mannophosphoinositides encapsulated in liposomes containing lipid A

Abstract

Mycobacterial mannophosphoinositides (PIMs) encapsulated in liposomes made of egg phosphatidylcholine (EPC) and cholesterol (CH) (2:1.5 molar ratio) were able to induce humoral and delayed type hypersensitivity (DTH, foot-pad swelling reaction) responses in mice without the help of any carrier protein. Animals immunized with this glycophospholipid antigen demonstrated enhanced percent survival on intravenous challenge with virulent M. tuberculosis. On fractionation of PIMs, pentamannophosphoinositide (PIM5) was found to induce higher antibody and DTH reaction and proved to be more immunoprotective than other fractions. Inclusion of lipid A as immunomodulator in liposomes containing PIMs or PIM5 resulted in a significantly increased immune response. Further, mice immunized with PIMs or PIM5 in lipid A-containing liposomes exhibited decreased mortality on challenge with M. tuberculosis H37Rv, which was comparable to BCG vaccinated animals.

Immunomodulation of alveolar epithelial cells by Mycobacterium tuberculosis phosphatidylinositol mannosides results in apoptosis

“…Mycobacterium tuberculosis H 37 Rv was grown on the modified liquid synthetic Youman's medium as a stationary pellicle culture at 37°C. The cultures were grown for 4-5 weeks without being disturbed, followed by harvesting cells in early stationary phase and PIM were isolated as described previously (17). Briefly, total lipids were extracted and PIM were isolated from the total lipids by dry column chromatography technique.…”

Nitric oxide participates in the immune response against Neisseria meningitidis serogroup B

“…), meanwhile the third group was also immunised as scheduled for group 2 but 30 min before each immunisation the mice received a single dose of LNMMA (10 mg kg 31 , i.p.). Finally, 56 days after the ¢rst immunisation, DTH was evaluated by speci¢c food-pad swelling [11] 48 h after the injection of Nm derived proteoliposome (50 Wg). At this point, samples of blood were obtained to evaluate the serum speci¢c anti-proteoliposome IgG response by ELISA.…”