Principle

DOE-SPEC-1142-2001

1. SCOPE. This specification is for beryllium lymphocyte proliferation tests (BeLPT) used for

detecting an individual's sensitivity to beryllium and for clinical evaluation and diagnosis of

patients for chronic beryllium disease. This specification should be used in all contracts with

laboratories for the purchase of BeLPT Services.

2. BACKGROUND. Beryllium is a lightweight metal that can cause a chronic granulomatous

disease called berylliosis and more commonly chronic beryllium disease (CBD). The

disability associated with CBD is primarily due to lung damage caused by an immune

response to beryllium retained in the lung. Development of this disease process is a function

of exposure, an individual's ability to mount a beryllium-specific, cell-mediated immune

response to beryllium (called sensitivity), their ability to develop granulomatous responses

and possibly other factors.

Testing for an individual's sensitivity to beryllium using an in-vitro assay is currently used:

as a screening assay; as part of the diagnostic criteria for chronic beryllium disease; and for

surveillance in identifying unhealthy working conditions. The following protocols have been

developed to optimize and standardize beryllium sensitivity testing.

These procedures have been shown to require some degree of experience. Individuals

requesting studies dealing with beryllium sensitization or CBD status should employ

facilities with an established and continuing record of satisfactory performance.

3. PRINCIPLE

3.1.

When a lymphocyte T cell antigen receptor recognizes a specific antigenic substance

bound to an HLA Class I or II molecule, the T cell responds in a variety of ways (for

example secreting inflammatory cytokines and/or undergoing cell division). Each T

lymphocyte expresses only a single T cell antigen receptor. When sufficient numbers

of specific T cells are present (usually greater than l/10,000), the response of specific

T cells can be detected clinically by either in-vitro or in-vivo testing. The in-vivo

response is usually measured as a delayed hypersensitivity skin test. The in-vitro T

cell response is normally measured by recording the proliferation response of the

cells. When an individual has a clinically measurable response to a specific antigen,

that individual is said to be sensitive or hypersensitive to that antigen.

3.2.

Beryllium can be a component of antigens and is associated with a granulomatous

hypersensitivity disorder in a small number (such as 5%) of individuals in an exposed

population. Large numbers of CD4+ T-lymphocytes accumulate in the lung in chronic

beryllium disease (Rossman et al, 1988, and Saltini et al, 1989). The reactivity of

these lymphocytes to beryllium provides a specific and sensitive laboratory test for

differentiating chronic beryllium disease from sarcoidosis (Rossman et al, 1988). In

chronic beryllium disease, the beryllium reactivity of lymphocytes obtained by

bronchoalveolar lavage is generally greater than the reactivity of lymphocytes

obtained from the peripheral blood. By measuring the reactivity of lymphocytes

obtained from the peripheral blood, beryllium sensitivity can also be detected in

workers without disease (Kreiss et al, 1993). Some of the workers without disease