Preclinical evaluation of magainin-A as a contraceptive antimicrobial agent  Aranha Clara, Ph.D., Dhananjay D. Manjramkar, M.V.Sc., Venkatarami K. Reddy, Ph.D.  Fertility and Sterility  Volume 81, Issue 5, Pages 1357-1365 (May 2004) DOI: 10.1016/j.fertnstert.2003.09.073

FIGURE 1 Dose-dependent inhibition of sperm motility in monkeys by magainin-A. Fresh aliquots of semen (blue squares) and swim-up sperm (orange circles) were incubated with twofold serial dilutions of magainin-A. The effect of magainin-A on sperm motility was evaluated by Sander-Cramer assay. Complete sperm immobilization was observed with 800–1,000 μg of magainin-A. Clara. Magainin-A and vaginal contraception. Fertil Steril 2004. Fertility and Sterility 2004 81, 1357-1365DOI: (10.1016/j.fertnstert.2003.09.073)

FIGURE 2 Photomicrographs of (A) control and (B) magainin-A-treated spermatozoa of monkey. Complete sperm immobilization was seen after treatment. Spermatozoa were stained with the Papanicolaou method. Original magnification, ×100. Clara. Magainin-A and vaginal contraception. Fertil Steril 2004. Fertility and Sterility 2004 81, 1357-1365DOI: (10.1016/j.fertnstert.2003.09.073)

FIGURE 3 Dose-dependent inhibition of cell viability, by nisin. Cells were incubated with twofold serial dilutions of nisin, and the extent of conversion of MTT dye to formazan was measured by spectrophotometer. The susceptibility of cells to nisin was found to be in the order of sperm (red diamonds) < RBCs (green circles) and HeLa (orange triangles). Control wells (blue squares) without magainin-A did not show any change in viability. Clara. Magainin-A and vaginal contraception. Fertil Steril 2004. Fertility and Sterility 2004 81, 1357-1365DOI: (10.1016/j.fertnstert.2003.09.073)

FIGURE 4 Vaginal smears in (A) controls and (B) after 14 days intravaginal administration of magainin-A in monkey. The smears were stained with the Papanicolaou method. No treatment-related changes in the vaginal cell morphology were observed. Original magnification, ×100. Clara. Magainin-A and vaginal contraception. Fertil Steril 2004. Fertility and Sterility 2004 81, 1357-1365DOI: (10.1016/j.fertnstert.2003.09.073)

FIGURE 5 Dose-dependent hemolysis of RBCs by magainin-A in monkey. Fresh aliquots of RBCs were incubated with twofold serial dilutions of magainin-A, and the extent of RBC lysis was monitored by spectrophotometer. Total hemolysis of RBCs was observed with 4 μL of 0.1% Triton X100. Each bar represents the mean ± SD of three observations. Clara. Magainin-A and vaginal contraception. Fertil Steril 2004. Fertility and Sterility 2004 81, 1357-1365DOI: (10.1016/j.fertnstert.2003.09.073)

FIGURE 6 Dose-dependent growth inhibition of pathogens by magainin-A treatment. Standard strains and clinical isolates of various pathogens were incubated with twofold serial dilutions of magainin-A. The MIC of magainin-A required to inhibit the growth of pathogens was measured by ELISA. The order of susceptibility was S. aureus (purple squares) and E. coli (blue diamonds) followed by C. albicans (orange triangles) and P. aeruginosa (black line). The clinical isolates of E. coli (green diamonds) and S. aureus (red squares) were less susceptible than their standard counterparts. Clara. Magainin-A and vaginal contraception. Fertil Steril 2004. Fertility and Sterility 2004 81, 1357-1365DOI: (10.1016/j.fertnstert.2003.09.073)