Stressed stability and protective efficacy of lead lyophilized formulations of ID93+GLA-SE tuberculosis vaccine.

With the recent exception of coronavirus disease 2019 (COVID-19), tuberculosis (TB) causes more deaths globally than any other infectious disease, and approximately 1/3 of the world's population is infected with Mycobacterium tuberculosis (Mtb). However, encouraging progress in TB vaccine development has been reported, with approximately 50% efficacy achieved in Phase 2b clinical testing of an adjuvanted subunit TB vaccine candidate. Nevertheless, current lead vaccine candidates require cold-chain transportation and storage. In addition to temperature stress, vaccines may be subject to several other stresses during storage and transport, including mechanical, photochemical, and oxidative stresses. Optimal formulations should enable vaccine configurations with enhanced stability and decreased sensitivity to physical and chemical stresses, thus reducing reliance on the cold chain and facilitating easier worldwide distribution. In this report, we describe the physicochemical stability performance of three lead thermostable formulations of the ID93 + GLA-SE TB vaccine candidate under various stress conditions. Moreover, we evaluate the impact of thermal stress on the protective efficacy of the vaccine formulations. We find that formulation composition impacts stressed stability performance, and our comprehensive evaluation enables selection of a lead single-vial lyophilized candidate containing the excipient trehalose and Tris buffer for advanced development.

Examination of Fluconazole-Induced Alopecia in an Animal Model and Human Cohort.

Fluconazole-induced alopecia is a significant problem for patients receiving long-term therapy. We evaluated the hair cycle changes of fluconazole in a rat model and investigated potential molecular mechanisms. Plasma and tissue levels of retinoic acid were not found to be causal. Human patients with alopecia attributed to fluconazole also underwent detailed assessment and in both our murine model and human cohort fluconazole induced telogen effluvium. Future work further examining the mechanism of fluconazole-induced alopecia should be undertaken.

Development of a thermostable nanoemulsion adjuvanted vaccine against tuberculosis using a design-of-experiments approach.

BACKGROUND: Adjuvants have the potential to increase the efficacy of protein-based vaccines but need to be maintained within specific temperature and storage conditions. Lyophilization can be used to increase the thermostability of protein pharmaceuticals; however, no marketed vaccine that contains an adjuvant is currently lyophilized, and lyophilization of oil-in-water nanoemulsion adjuvants presents a specific challenge. We have previously demonstrated the feasibility of lyophilizing a candidate adjuvanted protein vaccine against Mycobacterium tuberculosis (Mtb), ID93 + GLA-SE, and the subsequent improvement of thermostability; however, further development is required to prevent physicochemical changes and degradation of the TLR4 agonist glucopyranosyl lipid adjuvant formulated in an oil-in-water nanoemulsion (SE). MATERIALS AND METHODS: In this study, we took a systematic approach to the development of a thermostable product by first identifying compatible solution conditions and stabilizing excipients for both antigen and adjuvant. Next, we applied a design-of-experiments approach to identify stable lyophilized drug product formulations. RESULTS: We identified specific formulations that contain disaccharide or a combination of disaccharide and mannitol that can achieve substantially improved thermostability and maintain immunogenicity in a mouse model when tested in accelerated and real-time stability studies. CONCLUSION: These efforts will aid in the development of a platform formulation for use with other similar vaccines.

Dietary Docosahexaenoic Acid and trans-10, cis-12-Conjugated Linoleic Acid Differentially Alter Oxylipin Profiles in Mouse Periuterine Adipose Tissue.

Diets containing high n-3 polyunsaturated fatty acids (PUFA) decrease inflammation and the incidence of chronic diseases including cardiovascular disease and nonalcoholic fatty liver disease while trans-fatty acids (TFA) intake increases the incidence of these conditions. Some health benefits of n-3 PUFA are mediated through the impact of their oxygenated metabolites, i.e. oxylipins. The TFA, trans-10, cis-12-conjugated linoleic acid (CLA; 18:2n-6) is associated with adipose tissue (AT) inflammation, oxidative stress, and wasting. We examined the impact of a 4-week feeding of 0, 0.5, and 1.5% docosahexaenoic acid (DHA; 22:6n-3) in the presence and absence of 0.5% CLA on AT oxylipin profiles in female C57BL/6N mice. Esterified oxylipins in AT derived from linoleic acid (LNA), alpha-linolenic acid (ALA), arachidonic acid (ARA), eicosapentaenoic acid (EPA), DHA, and putative from CLA were quantified. CLA containing diets reduced AT mass by ~62%. Compared with the control diet, the DHA diet elevated concentrations of EPA-and DHA-derived alcohols and epoxides and LNA-derived alcohols, reduced ARA-derived alcohols, ketones, epoxides, and 6-keto-prostaglandin (PG) F1α (P < 0.05), and had mixed effects on ALA-derived alcohols. Dietary CLA lowered EPA-, DHA-, and ALA-derived epoxides, ARA-derived ketones and epoxides, and ALA-derived alcohols. While dietary CLA induced variable effects in EPA-, DHA-, and LNA-derived alcohols and LNA-derived ketones, it elevated ARA-derived alcohols and PGF1α, PGF2α, and F2-isoprostanes. DHA counteracted CLA-induced effects in 67, 57, 43, and 29% of total DHA-, ARA-, EPA-, and ALA-derived oxylipins, respectively. Thus, CLA elevated proinflammatory oxylipins while DHA increased anti-inflammatory oxylipins and diminished concentration of CLA-induced pro-inflammatory oxylipins in AT.

Lyophilization of an Adjuvanted Mycobacterium tuberculosis Vaccine in a Single-Chamber Pharmaceutical Cartridge.

Although substantial effort has been made in the development of next-generation recombinant vaccine systems, maintenance of a cold chain is still typically required and remains a critical challenge in effective vaccine distribution. The ability to engineer alternative containment systems that improve distribution and administration represents potentially significant enhancements to vaccination strategies. In this work, we evaluate the ability to successfully lyophilize a previously demonstrated thermostable tuberculosis vaccine formulation (ID93 + GLA-SE) in a cartridge format compared to a traditional vial container format. Due to differences in the shape of the container formats, a novel apparatus was developed to facilitate lyophilization in a cartridge. Following lyophilization, the lyophilizate was assessed visually, by determining residual moisture content, and by collecting melting profiles. Reconstituted formulations were assayed for particle size, protein presence, and GLA content. Based on assessment of the lyophilizate, the multicomponent vaccine was successfully lyophilized in both formats. Also, the physicochemical properties of the major components in the formulation, including antigen and adjuvant, were retained after lyophilization in either format. Ultimately, this study demonstrates that complex formulations can be lyophilized in alternative container formats to the standard pharmaceutical glass vial, potentially helping to increase the distribution of vaccines.

Staining and Transfer Techniques for SDS-PAGE Gels to Minimize Oil-in-Water Emulsion Adjuvant Interference.

Adjuvants in modern vaccines boost and shape immune responses and allow for antigen dose-sparing. Analysis of protein antigens in the presence of adjuvants can prove challenging, especially if the adjuvant interferes with visualization of the protein band on an SDS-PAGE gel. In this chapter, a variety of different techniques are presented to mitigate the interference of a nanoemulsion adjuvant, GLA-SE, with different recombinant proteins of varying molecular weight by addressing sample preparation and staining methods.

Interactions Between Antigens and Nanoemulsion Adjuvants: Separation and Characterization Techniques.

Determining the association of vaccine components in a formulation is of interest for designing and optimizing well characterized vaccines. Three methods are described to assess interactions between protein antigens and oil-in-water nanoemulsion adjuvants. The methods include (1) ultracentrifugation to measure free versus adjuvant-associated protein, (2) size exclusion chromatography (SEC) to qualitatively assess existing interactions, and (3) Native PAGE as a means to visualize the formulation run in its native state on a polyacrylamide gel. As with many techniques, the methods alone are not definitive, but data from multiple orthogonal assays can provide a more complete picture of protein-adjuvant interactions.

Vitamin A metabolism and mucosal immune function are distinct between BALB/c and C57BL/6 mice.

The vitamin A metabolite retinoic acid (RA) has been reported to suppress Th1 responses and enhance Th2 responses. Here, we investigated whether differences in vitamin A metabolism could underlie the differences between C57BL/6 and BALB/c mice, which are reportedly seen as Th1 and Th2 responders, respectively. BALB/c mice were shown to have higher intestinal epithelial expression of RALDH1 (where RALDH is retinaldehyde dehydrogenase), and, consequently, higher RALDH activity in MLN-DCs, leading to an increased ability to induce IgA class switching in B cells. Furthermore, within BALB/c mice, induction of IgA secretion as well as increased accumulation of regulatory T cells (Treg) in the intestinal lamina propria was observed. Additionally, as BALB/c mice are more resistant to dextran sulphate sodium (DSS) induced colitis, mice that lacked vitamin A in their diet had a more severe form of DSS-induced colitis compared to control mice. Therefore, the level of RA production and consequently the degree of RA-mediated signaling is crucial for the efficiency of the mucosal immune system.

DHA concentration of red blood cells is inversely associated with markers of lipid peroxidation in men taking DHA supplement.

An increase in the proportion of fatty acids with higher numbers of double bonds is believed to increase lipid peroxidation, which augments the risk for many chronic diseases. (n-3) Polyunsaturated fatty acids provide various health benefits, but there is a concern that they might increase lipid peroxidation. We examined the effects of docosahexaenoic acid [22:6 (n-3)] supplementation on lipid peroxidation markers in plasma and red blood cells (RBC) and their associations with red blood cell and plasma fatty acids. Hypertriglyceridemic men (n = 17 per group) aged 39-66 years participated in a double-blind, randomized, placebo-controlled, parallel study. They received no supplements for the first 8 days and then received 7.5 g/day docosahexaenoic acid oil (3 g/day docosahexaenoic acid) or olive oil (placebo) for 90 days. Fasting blood samples were collected 0, 45, and 91 days after supplementation. Docosahexaenoic acid supplementation did not change plasma or RBC concentrations of lipid peroxidation markers (total hydroxyoctadecadienoic acid, total hydroxyeicosatetraenoic acid, total 8-isoprostaglandin F2α, 7α-hydroxycholesterol, 7ß-hydroxycholesterol) when pre- and post-supplement values were compared. However, the post-supplement docosahexaenoic acid (DHA) concentration was inversely associated with RBC concentrations of ZE-HODE, EE-HODE, t-HODE, and total 8-isoprostaglandin F2α, (p<0.05). RBC concentration of hydroxycholesterol was also inversely associated with DHA but it did not attain significance (p = 0.07). Our results suggest that increased concentration of DHA in RBC lipids reduced lipid peroxidation. This may be another health benefit of DHA in addition to its many other health promoting effects.

A novel mouse model of nonalcoholic steatohepatitis with significant insulin resistance.

Currently available models insufficiently reflect the pathogenic alternation of nonalcoholic steatohepatitis\NASH), such as insulin resistance. The present study aimed to characterize a novel NASH model caused by feeding the diet containing conjugated linoleic acid (CLA). In this study, mice were fed a control diet or the diet containing 0.5% CLA for 8 weeks. The insulin tolerance test (ITT) and homeostasis model assessment of insulin resistance (HOMA-IR) were used to determine the extent of insulin resistance. Liver lipotoxicity and inflammation were assessed by endoplasmic reticulum (ER) stress, autolipophagy, recruitment of Kupffer cells and hepatic stellate cell (HSC) activation. We found that liver weight was markedly increased, and histopathological examination showed marked macrosteatosis with focal hepatocellular death through apoptosis, and mild pericellular fibrosis with Kupffer cell recruitment and HSC activation, as well as light chain IIIß-positive cells and enhanced ER stress in mice fed the CLA-containing diet. Enhanced synthesis and reduced ß-oxidation of fatty acids resulted in their accumulation and lipotoxicity in hepatocytes. A biophotonic technology revealed lipid droplet accumulation in the liver from mice fed the CLA-containing diet, and Raman spectroscopic analysis indicated that these lipid droplets predominantly contained saturated fatty acids. Elevated fasting insulin levels, abnormal ITT and HOMA-IR confirmed the marked insulin resistance in these mice. Decreased phosphorylation of the insulin-signaling molecule Akt was partially responsible for the significant insulin resistance. In conclusion, Mice fed the diet containing CLA-developed steatohepatitis with marked insulin resistance, which is similar to the characteristics observed in NASH patients. The further characterization of this model would be particularly useful for revealing the critical role of insulin resistance in NASH development in conditions such as metabolic syndrome, diabetes and obesity.

The effect of docosahexaenoic acid on t10, c12-conjugated linoleic acid-induced changes in fatty acid composition of mouse liver, adipose, and muscle.

BACKGROUND: Concomitant supplementation of 1.5% docosahexaenoic acid (22:6 n-3; DHA) with 0.5% t10, c12-conjugated linoleic acid (18:2 n-6; CLA) prevented the CLA-induced increase in expression of hepatic genes involved in fatty acid synthesis and the decrease in expression of genes involved in fatty acid oxidation. The effect of CLA on fatty acid compositions of adipose tissue and muscle and whether DHA can prevent those CLA-induced changes in fatty acid composition is not known. METHODS: We investigated if DHA fed concomitantly with CLA for 4 weeks will prevent the CLA-induced changes in fatty acid compositions of liver, adipose, and muscle lipids in C57BL/6N female mice. We also examined changes in expression of adipose tissue genes involved in fatty acid synthesis, oxidation, uptake, and lipolysis. RESULTS: CLA supplementation increased liver fat and decreased total n-3 polyunsaturated fat (PUFA) concentration. DHA not only prevented the CLA-induced changes in liver fat, but also increased n-3 PUFA by >350% as compared with the control group. CLA decreased adipose weight and the expression of genes involved in fatty acid synthesis, oxidation, and uptake and increased that of uncoupling protein 2 (UCP2). Supplementing DHA along with CLA increased adipose n-3 PUFA by >1000% compared with control group, but did not prevent the CLA-induced changes in mass or gene expression. Both CLA and DHA were incorporated into muscle lipids, but had minor effects on fatty acid composition. CONCLUSIONS: Liver, adipose tissue, and muscle responded differently to CLA and DHA supplementation. DHA prevented CLA-induced increase in liver fat but not loss of adipose mass.

Docosahexaenoic acid prevents trans-10, cis-12-conjugated linoleic acid-induced nonalcoholic fatty liver disease in mice by altering expression of hepatic genes regulating fatty acid synthesis and oxidation.

BACKGROUND: Concomitant supplementation with docosahexaenoic acid (22:6 n-3; DHA) prevented trans-10, cis-12-conjugated linoleic acid (CLA)-induced nonalcoholic fatty liver disease (NAFLD) and insulin resistance. The effective dose of DHA and mechanisms involved are poorly understood. METHODS: We examined the ability of DHA (0.5% and 1.5%) to prevent increases in NAFLD and homeostatic model assessment of insulin resistance (HOMA-IR) induced by CLA (0.5%) when fed concomitantly for 4 weeks to C57BL/6N female mice. We also examined changes in expression of hepatic genes involved in fatty acid synthesis and oxidation. RESULTS: CLA supplementation increased liver triglycerides (TG) and HOMA-IR by 221% and 547%, respectively, and decreased mass of different adipose depots by 65%-90% when compared to those in the control group. When fed concomitantly, DHA prevented CLA-induced increases in liver TG and circulating insulin with varying efficiency, but it did not prevent loss in adipose tissue mass. In the CLA+0.5% DHA group, the liver TG did not differ from those in the control group, but circulating insulin and HOMA-IR were 285% and 264%, respectively. In the CLA+1.5% DHA group, liver TG were 54% lower than those in the control group, but circulating insulin concentration and HOMA-IR did not differ between these two groups. CLA increased the expression of hepatic genes involved in fatty acid synthesis and decreased the expression of genes involved in fatty acid oxidation, and 1.5% DHA prevented changes in the expression of hepatic genes caused by CLA. CONCLUSIONS: Response of different tissues to CLA and DHA varied; CLA was more potent than DHA in altering depot fat and insulin concentrations.

Prevention of insulin resistance by n-3 polyunsaturated fatty acids.

PURPOSE OF REVIEW: Review results from recent human and animal studies regarding the effects of n-3 polyunsaturated fatty acid (PUFA) in the prevention of insulin resistance. RECENT FINDINGS: Overall, results from animal studies indicate that fish oil and individual n-3 PUFA [alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA)] prevented insulin resistance in animal models; results from two studies in mice showed that EPA increased insulin secretion. ALA, EPA, and DHA may act at different sites and involve different mechanisms. Fish oil or purified EPA reduced insulin resistance in some but not other human studies in normal weight and obese individuals. Discrepancies may be due to differences in health status of participants, macronutrient, fatty acid, and antioxidant nutrient composition of basal diet; amount, duration, and fatty acid composition of n-3 PUFA, and methods used to assess insulin resistance. Moderate amounts of n-3 PUFA did not improve or deteriorate glucose control in type 2 diabetics. SUMMARY: n-3 PUFA supplementation has clinical significance in the prevention and reversal of insulin resistance. However, increased intake of n-3 PUFA should be part of an overall healthy lifestyle that includes weight control, exercise, and reduction in the intake of refined sugars, n-6, saturated, and trans fatty acids.

DHA supplementation decreases serum C-reactive protein and other markers of inflammation in hypertriglyceridemic men.

Dietary (n-3) PUFA reduce inflammation, an independent risk factor for cardiovascular disease. The antiinflammatory effects of docosahexaenoic acid (DHA) in hypertriglyceridemic men have not been previously reported, to our knowledge, and were the focus of this study. Hypertriglyceridemic men (n = 17 per group) aged 39-66 y, participated in a double-blind, randomized, placebo-controlled parallel study. They received no supplements for the first 8 d and then received either 7.5 g/d DHA oil (3 g DHA/d) or olive oil (placebo) for the last 90 d. Blood samples were collected from fasting men on study days -7, 0, 45, 84, and 91. DHA supplementation for 45 and 91 d decreased the number of circulating neutrophils by 11.7 and 10.5%, respectively (P < 0.05). It did not alter the circulating concentrations of other inflammatory markers tested within 45 d, but at 91 d it reduced (P < 0.05) concentrations of C-reactive protein (CRP) by 15%, interleukin-6 by 23%, and granulocyte monocyte-colony stimulating factor by 21% and DHA increased the concentration of antiinflammatory matrix metalloproteinase-2 by 7%. The number of circulating neutrophils was positively associated with the weight percent (wt %) of 20:4(n-6) in RBC lipids, and negatively to the wt % of 20:5(n-3) and 22:6(n-3). Concentrations of CRP and serum amyloid A were positively associated with the sum of SFA and negatively with the wt % of 18:1(n-9) and 17:0 in RBC lipids; CRP was also positively associated with the wt % of 20:2(n-6). The mean size of VLDL particles was positively associated with plasma concentrations of neutrophils and CRP. In conclusion, DHA may lessen the inflammatory response by altering blood lipids and their fatty acid composition.

Flaxseed oil prevents trans-10, cis-12-conjugated linoleic acid-induced insulin resistance in mice.

Insulin resistance (IR) and non-alcoholic fatty liver disease (NAFLD) are found in 35 and 30 % of US adults, respectively. Trans-10, cis-12-conjugated linoleic acid (CLA) has been found to cause both these disorders in several animal models. We hypothesised that IR and NAFLD caused by CLA result from n-3 fatty acid deficiency. Pathogen-free C57BL/6N female mice (aged 8 weeks; n 10) were fed either a control diet or diets containing trans-10, cis-12-CLA (0.5 %) or CLA+flaxseed oil (FSO) (0.5 %+0.5 %) for 8 weeks. Weights of livers, concentration of circulating insulin, values of homeostatic model 1 (HOMA1) for IR and HOMA1 for beta cell function were higher by 160, 636, 985 and 968 % in the CLA group compared with those in the control group. FSO decreased fasting glucose by 20 % and liver weights by 37 % compared with those in the CLA group; it maintained circulating insulin, HOMA1-IR and HOMA1 for beta cell function at levels found in the control group. CLA supplementation decreased n-6 and n-3 wt% concentrations of liver lipids by 57 and 73 % and increased the n-6:n-3 ratio by 58 % compared with corresponding values in the control group. FSO increased n-6 and n-3 PUFA in liver lipids by 33 and 342 % and decreased the n-6:n-3 ratio by 70 % compared with corresponding values in the CLA group. The present results suggest that some adverse effects of CLA may be due to n-3 PUFA deficiency and that these can be corrected by a concomitant increase in the intake of alpha-linolenic acid, 18 : 3n-3.