The immunomodulatory effect of neem (Azadirachtaindica)‎ seed aqueous, ethanolic extracts and Candida albicans cell wall mannoproteins on immune response in mice vaccinated with Brucella Rev-1

Abstract EN

In the present study, the immunomodulatory effect of Neem (Azadirachtaindica) seed aqueous, ethanolic extracts and Candida albicans cell wall mannoproteins on the immune response of mice vaccinated with Brucella Rev-1 vaccine was investigated.

The study was conducted on two main groups (160 mice for each group), Each group was divided into eight subgroups 20 mice for each (I : treated with distilled water, II : treated with the Brucella Rev-1 vaccine, III: treated with mannoproteins, IV : treated with neem aqueous extract, V : treated with neemethanolic extract, VI, VII and VIII : treated with mannoproteins, neem aqueous extract and neemethanolic extract, respectively, then they were vaccinated with Brucella Rev-1).

All these treatments were carried out on day 1 and then vaccinated with brucella Rev-1 vaccine on day 4 .Then the mice were tested as follows , on day 8 after vaccination(serum IFN-γ level), day 21 for (anti-Brucella antibody titer).

The doses of both plant extracts and mannoproteins represented 10 % of the calculated LD50 (neem extracts : 3.8096 g / Kg mannoproteins : 5.7144 mg / Kg), which were given subcutaneously.

Mice of the second main group were injected with the immune suppressive drug prednisolone (5mg / Kg) 5 days prior to the treatments, which carried out on mice of the first main group.

The results demonstrated clear immunomodulatory effects (improvement of non-specific, humoral immunity) of the tested immunomodulators in mice vaccinated with Brucella Rev-1 as compared with mice that were not treated with Neem extracts or mannoproteins.

In this regard, the interferon-γ showed a significant increase (P ≤ 0.01) serum level in immunomodulatortreated and -vaccinated mice in comparison with negative and positive groups, and again group VII showed the highest increase.

The anti-Brucella antibodies assessed by indirect Immunoflourescent test also showed a significant increase titer in immunomodulatortreated and -vaccinated mice in comparison with negative and positive groups.

Conclusion : The aqueous and ethanolicNeem seed extract reported the highest enhancement in all immunological parameters employed in comparison with mannoproteins of Candida albicans cell wall.