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 Tareq J. Faal ,Adhia, A. Hussein ,Mohammad K Faraj and Al-Ramahy A.K

Abstract

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.