Search PubMed⌕ Search

Biomedical subjects

Jay E Slater

Publications and source records attributed to Jay E Slater.

8 recordsLinked to original sources
PubMed2006

beta-Glucans in standardized allergen extracts.

BACKGROUND: Allergen extracts contain variable quantities of bacterial endotoxin. Recent studies have suggested that (1-->3)-beta-D-glucans (beta-glucans), also microbial cell wall components, may have adjuvant properties that could affect allergen immunotherapy. OBJECTIVE: To determine the quantities of beta-glucans in standardized allergen extracts. MATERIALS AND METHODS: Ninety-four lots of 13 standardized allergen extracts were tested for beta-glucan content by Glucatell assay, and for endotoxin content by a specific, chromogenic formulation of the Limulus amebocyte lysate test. RESULTS: Standardized allergen extracts contain variable quantities of endotoxins and beta-glucans. As in our previous work, endotoxin activity was greatest in cat pelt and Dermatophagoides farinae, and least in the pollens. There was no correlation between endotoxin and beta-glucan levels (r = 0.1887; P = 0.07). beta-Glucan content was highest for grass pollen (median content, 10.6 ng/ml; range, 0.4-41.8 ng/ml), ragweed pollen (32.9 ng/ml; range, 6.5-41.2 ng/ml), and cat pelt (25.5 ng/ml; range, 16.7-41.1 ng/ml), and lowest for cat hair (4.9 ng/ml; range, 1.2-10.3 ng/ml), D. farinae (1.2 ng/ml; range, 0.4-5.2 ng/ml) and Dermatophagoides pteronyssinus (1.8 ng/ml; range, 0.4-6.7 ng/ml). CONCLUSIONS: beta-Glucans are present in standardized allergen extracts. The effects of these quantities of beta-glucans on allergen immunotherapy and allergen skin testing require further study.

Allergens↗
PubMed2005

Bacterial 16S ribosomal DNA in house dust mite cultures.

BACKGROUND: Allergen extracts prepared from Dermatophagoides farinae contain significantly more endotoxin than Dermatophagoides pteronyssinus extracts, and extracts from both mite extracts contain more endotoxin than pollen extracts. Attempts to culture bacteria from mite cultures have failed to establish the sources of the endotoxin. OBJECTIVE: To determine the bacterial sources of endotoxin in mite extracts. METHODS: Live mites of both species were obtained from 2 sources, DNA was extracted from the mites, and DNA encoding bacterial 16S ribosomal RNA was amplified by using specific primers. The amount of bacterial DNA in each mite DNA sample was determined by quantitative PCR using an internal standard, and sequence homologies were determined from amplifications performed by using a high-fidelity DNA polymerase. RESULTS: DNA from D farinae appeared to contain between 11-fold and 24-fold more 16S ribosomal gene copies than the genomic DNA from D pteronyssinus (P < or = .003). Sequence analysis indicated the dominant presence of at least 3 phylogenetic clusters of Bartonella species (henselae, quintana, vinsonii, and grahamii), as well as uncharacterized alpha-proteobacteria, from both D farinae and D pteronyssinus. In a few clones, sequences from Escherichia coli, Pseudomonas species, and Acinetobacter species were also identified. CONCLUSION: House dust mite DNA contains evidence of Bartonella and other Gram-negative species. These Gram-negative species are likely to be the sources of the endotoxin found in mite allergenic extracts.

Animals↗
PubMed2004

Recombinant allergens in the US.

Recombinant allergens may increase the safety and efficacy of allergen immunodiagnostics and immunotherapy, and may prove to be excellent tools for the standardization of existing, natural allergens. However, there are several biological and regulatory issues that need to be addressed as these products are moved from bench to bedside. This article discusses some of these issues.

Allergens↗
PubMed2004

Latex allergens.

Explore the source record for details and available documents.

Allergens↗
PubMed2003

Endotoxin content of standardized allergen vaccines.

BACKGROUND: Endotoxin is a ubiquitous and potent proinflammatory agent. Previous limited studies suggest that it is pres-ent in allergen vaccines and that this could affect the safety and efficacy of allergen immunotherapy. The endotoxin content of standardized allergen vaccines is unknown. OBJECTIVE: The purpose of this study was to quantify the amount of endotoxin contained in standardized allergen vaccines. METHODS: The endotoxin content of 14 allergen vaccines was measured by using the Limulus amebocyte lysate (LAL) gel-clot assay. To account for (1,3)-beta-d-glucan and protease interference, vaccines were selectively depleted of endotoxin and then retested with the gel-clot assay. Proteases were also heat-inactivated in selected vaccines. Fifty-eight lots of vaccines were tested, including at least two manufacturers per vaccine. RESULTS: The endotoxin content of the 58 vaccines ranged from undetectable to 34,000 EU/mL. Cat pelt (12,735 EU/mL; range, 5177 to 33,805) had significantly more endotoxin activity than cat hair (2883 EU/mL; range, 1 to 16,962), and Dermatophagoides farinae extracts (4619 EU/mL; range, 849 to 8485) had more than Dermatophagoides pteronyssinus (11 EU/mL; range, 1 to 34). Grass (160 EU/mL; range, 3 to 1561) and ragweed pollen (341 EU/mL; range, 8 to 1697) vaccines contained less endotoxin. (1,3)-beta-d-glucan interference was significant (>10%) only in three ragweed vaccines and two grass vaccines. Heat inactivation had no effect. There were considerable differences in endotoxin content of the same vaccines made by different manufacturers. CONCLUSIONS: The endotoxin content of standardized allergen vaccines is extremely variable. Interference by proteases and (1,3)-beta-d-glucans is minimal. The effects of the high levels of endotoxin in some vaccines on the immunomodulatory changes associated with allergen immunotherapy require further study.

Allergens↗
PubMed2003

Sample size considerations for establishing clinical bioequivalence of allergen formulations.

Bioequivalence of formulations must be established by proving that the differences between the formulations are within a specified interval according to Equation 1, the Interval Hypothesis. Explicit estimates of sample size determined from Equation 8 and listed in Table 1 are qualitatively larger than those that would be determined from Equation 2, the Hypothesis of No Difference. Equation 8 was derived from the TOST procedure; other valid methods should yield comparable results. In any context, this discussion has illustrated that the failure to demonstrate a difference is not sufficient to demonstrate equivalence, and that a properly powered equivalence study of allergen formulations will generally demand many more than four study subjects.

Allergens↗