Nutrition Now - PB8 Immune Probiotic Supplement - 60 Capsules PB 8 Immune Probiotic Supplement helps support the immune system with 10 probiotic strains and 10 billion good bacteria. PB 8 provides digestive support and helps support the immune system with 10 billion beneficial bacteria per serving and a proprietary blend of 10 probiotic strains. Only one capsule per day provides probiotics like Bifidobacterium lactis (Bl-04) and Bifidobacterium lactis (HN019) to help support the immune system.