The new nano-complex, Hep-c, improves the immunogenicity of the hepatitis B vaccine.

Prevention of hepatitis B requires a vaccine that stimulates the humoral and cellular immune responses in a balanced manner, particularly those associated with Th1 and cytotoxic T cells. Alum adjuvant is currently used in the hepatitis B vaccine formulations but it lacks the efficiency of establishing such immune responses. Therefore, for accessing a suitable vaccine to prevent this fatal disease, it is essential to design and construct a new adjuvant which can overcome the limitations of the alum adjuvant and can stimulate a strong Th1 response as used along with it. In the present study, the adjuvant effect of Hep-c, the first nano-complex which was synthesized by nanochelating technology to improve the immunogenicity of the vaccine against hepatitis B, had been evaluated. Female Balb/c mice were divided into 7 groups and were injected with 10µg/ml of the hepatitis B vaccine and different doses of Hep-c for 3 times. Groups merely treated with the vaccine, Hep-c or phosphate buffered solution were used as control. Total specific antibody, IgG1, IgG2a, IgG2b, IgM, interleukin-4 (IL-4) and interferon-gamma (IFN-γ) levels were examined by the ELISA method. The proliferative response of the splenocytes was evaluated using bromodeoxyuridine assay. Results showed that immunization with hepatitis B vaccine and Hep-c increased the lymphocyte proliferation and specific IgM and IgG2a compared to the hepatitis B vaccine immunized group. Also, this nano-complex significantly increased the IFN-γ and IL-4 cytokine levels compared to the hepatitis B vaccine immunized group. Our findings show that Hep-c can not only preserve the alum capacity to effectively stimulate production of the antibodies but also cover its inefficiency in inducing Th1 response and prompting cellular immunity. Thus, by boosting the performance of the hepatitis B vaccine, it seemed that this nano-adjuvant has the suitable potential to be used in the commercial HBS vaccine formulation.

Fluoxetine competes with cortisol for binding to human serum albumin.

Human serum albumin (HSA) is an important protein that carries variety of substances like some hormones and drugs in blood. Pharmacological studies of the interaction of many drugs and HSA are reported during several decades, specially recently years. Interaction of cortisol and fluoxetine hydrochloride (FLX) (as a common anti-stress drug) with HSA (as their carrier in blood) has been studied separately by using different spectroscopic techniques. Here, considering the increment of anti-stress drugs consumption, conformational change of HSA in presence of cortisol and FLX in 50 mM tris buffer, at pH = 7.5 and 37°C, is investigated via pH meter, UV absorption and fluorescence spectroscopy and circular dichroism methods. pH meter findings indicate that the acid denaturation of HSA in the presence of drug and cortisol occurs in the similar manner and this pattern is different relative to the denaturation of HSA in the absence of two reagents. The results of the other techniques consistent with the pH meter findings show that FLX effects on the physiochemical properties of HSA are as that of Cortisol. In-vivo study in Rats confirms in-vitro findings which means blood cortisol level increased in the presence of FLX. Experimental results indicate that FLX and cortisol alter the structural aspects of HSA in similar manner, so, this findings lead to the following reasonable conclusion: "FLX is a competitive ligand for the binding of cortisol to HSA. Binding of FLX to HSA interferes to the interaction of cortisol-HSA."