Protective role of interferon against cytotoxcicity induced by rabies virus in mice

Abstract

Rabies remains an important public health problem in the world due to uncontrolled enzootic rabies, lack of safe efficient vaccines and poor information on the risk of contracting rabies post animal exposure. The lethality and mutagenic potential of challenge virus standard (CVS) was evaluated in mice. Mice were intracerebrally infected (MIC) with low, medium and high viral LD 50 (MICLD 50 ). Mice were subjected to immunomodulation using interferon (IFNα-2a) pre-infection. The infected groups pretreated with IFN-α 2a showed a higher survival rate than the infected group. Statistically significant increase in structural and numerical chromosomal aberrations and a decreased mitotic activity of mice bone marrow cells was observed post infection. Pretreatment of the infected groups with IFN α-2a showed a marked and significant reduction of these cytogenetic changes. The increased survival rate and reduced cytogenetic changes suggest that protection induced by interferon against rabies virus activity could be, at least partially, attributable to blockage of the replication of CVS strain of rabies virus. It could be concluded that interferon can be used as an immune enhancer to the application of vaccine administration.

A preliminary study of recombinant human interferon-α-2a activity against rabies virus in murine model

“…The increased survival rate and reduced cytogenetic changes suggest that protection induced by interferon against rabies virus activity could be, at least partially, attributable to blockage of the replication of CVS strain of rabies virus. [12] Similar observation was reported from study involving monkeys infected with rabies virus when administered by repeated intramuscular administration of human leukocyte interferon beginning 24 h after infection. [7] Bosko Postic et al, showed simultaneous inoculation of interferon and street rabies in rabbit in opposite hind limbs decreased the mortality but interferon in vitro failed to neutralise rabies virus.…”

“…The infected Swiss albino mice were observed for mortality upto 21 days. [12] The pre-exposure and post-exposure treatments of rhuIFN α-2a challenged with RV CVS were repeated in triplicate. All the infectious work was carried out in Biosafety level-2 cabinet.…”

Exogenous interferon prolongs survival of rabies infected mice

“…Our results were similar to that reported by Tohamy et al, where pre treatment of mice with IFN, 24 h before infection delayed the onset of specific rabies signs [31]. Therefore, based on development of characteristic signs of illness in the pre-exposure and post-exposure groups, we speculated that priming with interferon in the pre-exposure group can lead to local production of cytokines and recruitment of lymphocytes.…”

“…However, the mechanism behind the reported protective activity of exogenous interferon is not clear. Recently Tohamy et al, demonstrated that pretreating rabies infected mice with interferon significantly reduced cytogenetic changes [31]. These reports formed the basis of the present study which is an attempt to investigate the role of recombinant human interferon alpha (rhIFN a-2A) on prognosis and expression of innate immunity cytokines during rabies infection.…”