Effect of atorvastatin on humoral immune response to 23-valent pneumococcal polysaccharide vaccination in healthy volunteers: The StatVax randomized clinical trial.

BACKGROUND: The immunomodulatory effects of statins on vaccine response remain uncertain. Therefore, the objective of this study was to determine if atorvastatin enhances pneumococcal-specific antibody titer following 23-valent pneumococcal polysaccharide vaccination. METHODS: Double-blind, placebo-controlled, single-center randomized clinical trial entitled StatVax. Subjects were enrolled between June and July 2014 and followed up through September 2014. 33 healthy volunteers signed informed consent after volunteer sampling. 11 participants were excluded; 22 healthy volunteers without prior pneumococcal vaccination were enrolled and completed the study. Participants were randomized to receive a 28-day course of 40 mg atorvastatin (n = 12) or matching lactose placebo (n = 10). On day 7 of treatment, Pneumovax 23 was administered intramuscularly. The primary outcome was fold change in total pneumococcal-specific antibody titer determined by a ratio of post-vaccination titer over baseline titer. Secondary outcomes included serotype-specific pneumococcal antibody titer, seroconversion, complete blood counts (CBC), erythrocyte sedimentation rate (ESR), and serum cytokine analysis. RESULTS: Of the 22 randomized patients (mean age, 23.86; SD, 4.121; 11 women [50%]), 22 completed the trial. Total anti-pneumococcal antibody titer in the atorvastatin group went from a baseline mean of 32.58 (SD, 15.96) to 147.7 (SD, 71.52) µg/mL at 21 days post-vaccination while titer in the placebo group went from a mean of 30.81 (SD, 13.04) to 104.4 (SD, 45) µg/mL. When comparing fold change between treatment groups, there was a significant increase in fold change of total anti-pneumococcal antibody titer in the atorvastatin group compared to the placebo group (2-way ANOVA, p = .0177). CONCLUSIONS: Atorvastatin enhances antigen-specific primary humoral immune response to a T cell-independent pneumonia vaccination. Pending confirmation by larger cohort studies of target populations, peri-vaccination conventional doses of statins can become a novel adjuvant for poorly-immunogenic polysaccharide-based vaccines. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02097589.

Immune Modulatory Effects of Hypercholesterolemia: Can Atorvastatin Convert the Detrimental Effect of Hypercholesterolemia on the Immune System?

Many observations showed that hypercholesterolemia can disrupt immune response. Statin drugs that were used for the treatment of hypercholesterolemia patients can interfere in the regulation of the immune response and cytokine secretion. The primary aim of the current study was to investigate the immune response among treatment-naïve patients with hypercholesterolemia and healthy subjects. The secondary goal of the study was to determine whether atorvastatin can reverse the detrimental effect of hypercholesterolemia on the immune system. Peripheral blood mononuclear cells (PBMCs) were isolated from 50 patients afflicted with hypercholesterolemia who were treatment-naïve along with 50 sex/age-matched hypercholesterolemia patients receiving atorvastatin, and 50 sex/age-matched healthy subjects. Quantitative PCR and ELISA methods were used for gene and protein expression analysis of T helper 1 (Th1) and Th2 related cytokines. Additionally, the expression of the cluster of differentiation (CD) markers on T, B, and natural killer (NK) cells was measured by flow cytometry method. The results showed that hypercholesterolemia and atorvastatin down-regulated the expression of Th1-related cytokines and elevated the levels of Th2-related cytokines. The expression of cell surface markers, CD25 and CD69, was significantly decreased in the treatment-naïve, and atorvastatin groups. It seems that atorvastatin is not able to repair the deleterious effects of hypercholesterolemia on the immune system. Moreover, elevated levels of cholesterol along with the administration of atorvastatin tilt the Th1/Th2 balance in favor of Th2 and reduce T cell activation.