Chemical Inactivation of the Kveim Reagent

Abstract

In an attempt to identify the nature of the active principle, Kveim reagent was exposed to chemical fractionating agents. Thirty-one patients with sarcoidosis underwent simultaneous intradermal injection with fractionated and unfractionated Kveim material. Kveim reagent was stable in the presence of DNAse, RNAse, pronase, 95% phenol, neutral detergent, and to lipid extraction with chloroform-methanol. Kveim reagent was also stable in the presence of both 8 M urea (8MU) and 2-mercaptoethanol (2ME) when used alone. When both these agents were used together, Kveim reagent was inactivated. Fourteen patients had a positive test to unfractionated Kveim reagent; of these, only 2 gave a positive response to material fractionated by exposure to 8MU and 2ME. Simultaneous exposure to 8MU and 2ME was more likely to inactivate Kveim reagent (10/10 tests) than sequential exposure to 8MU and 2ME (2/4 tests). Chemical analysis of the fractionated material showed that it retained granuloma-generating activity despite the lack of carbohydrates. Protein loss in terms of total and relative amino acid composition was progressive and nonspecific throughout processing. These results are consistent with a protein-active principle which is dependent on three-dimensional structure.

Serum Amyloid A Regulates Granulomatous Inflammation in Sarcoidosis through Toll-like Receptor-2

“…Our initial studies of SAA were prompted by recognition that the biophysical properties of the granuloma-inducing component of sarcoidosis tissues had striking parallels to the properties of amyloid or prion fibrils (12,14,15). Despite the often intense staining of SAA in sarcoidosis granulomas, sites of SAA deposition were not associated with typical features of amyloid fibril aggregation as evidenced by the lack of widespread Congo red birefringence or staining with serum amyloid P. However, Congo red staining of amyloid or prion fibrils may significantly underestimate the presence of amyloid or prion proteins in tissues, suggesting there may be aggregates of SAA below the level of detection by this analytic method (27,28).…”

“…Our previous studies demonstrated clonal T-cell populations at Kveim reaction sites consistent with antigen-driven responses (13). Because the granuloma-inducing properties of sarcoidosis tissue extracts (Kveim reagent) have physicochemical properties similar to those of amyloid or prion fibrils (neutral detergent insolubility; relative heat, acid, nuclease, and protease resistance; and sensitivity to alkali and potent denaturants) (14), we hypothesized that host proteins with the potential to form poorly soluble aggregates or amyloid fibrils play a role in the development of epithelioid granulomas in sarcoidosis.…”

State of the Art. Potential Etiologic Agents in Sarcoidosis

“…These properties include the following: relative resistance to neutral detergents, heat, acidity, organic solvents, nucleases, and proteases (15,16). The fact that Kveim reactivity is abrogated by potent denaturants suggests a protein component is responsible for the granulomainducing activity (17). These physicochemical properties presumably reflect the same characteristics of the factors that cause granulomas in patients with systemic sarcoidosis.…”

Sarcoidosis: immunopathogenetic concepts and their clinical application

“…So far, the nature of the Kveim reagent remains obscure. Denaturing experiments have revealed that the active, granulomainducing principle should consist of a protein and depends on its three-dimensional structure [81].…”