Studies in a Murine Model Confirm the Safety of Griffithsin and Advocate Its Further Development as a Microbicide Targeting HIV-1 and Other Enveloped Viruses

Kouokam, Joseph Calvin; Lasnik, Amanda B.; Palmer, Kenneth E.

To validate the use of a murine model, we evaluated the toxicological effects of GRFT on PMBCs purified from mouse blood samples, in light of data described in our previous work on human PBMCs and cervico-vaginal cell lines [12] . As shown above, purified mPBMCs were not, or only moderately, affected by high concentrations of GRFT, in terms of viability and mitogenicity. In addition, IL-1b, IL-10 and TNF-α amounts in mPBMC culture supernatants were not altered by GRFT at concentrations of up to 4 μM. IL-6 concentrations were not affected by 1 μM GRFT, although a transient and moderate increase was observed after treatment with 4 μM at one day after treatment. These data indicate that GRFT does not boost release of the above four cytokines in mPBMCs, Figure 6 . Safety of a chronic dose of 2 mg/kg GRFT in mice. Mouse body (A) and spleen (B) weights were assessed after 10 daily s.c., intravaginal, and intraperitoneal administrations, respectively, of GRFT at 2 mg/kg or PBS; In addition, immune cell activation of splenocytes from these mice was evaluated by flow cytometry after dual fluorescent staining with FITC-conjugated anti-CD4 or CD19 mAb in combination, respectively, with PE-conjugated anti-B220 (C) or anti-CD69 (D). B220+, cells staining positive for B220 only (single positive); Ttotal B220+ represent B220 single positive and B220/CD19 double positive.