The collagenous nature of amianthoid degeneration of human costal cartilage.

Amianthoid (asbestoid) fibers in aging human costal cartilage are shown to be collagenous both by their electron microscopic appearance and solubilization by clostridial collagenase. The fibers differ morphologically from collagen of dermis, synovium, tendon, fibrocartilage and hyaline articular cartilage in dimension, contour and arrangement. They measure up to 1 mu in width, and their period length is 560 to 620 A.

Immunoglobin synthesis by fresh biopsy cells and established cell lines from Burkitt's lymphoma.

(1) Freshly dispersed cells from four Burkitt's lymphoma biopsies, and three `lymphoblast' cell lines (OB2, OB3 and OB6) derived from the tumour were tested for capacity to synthesize immunoglobulins . Using labelled amino acid incorporation, electrophoretic, radio-immunoelectrophoretic and ultracentrifugation techniques, it was possible to demonstrate the release of labelled proteins with antigenic characteristics of immunoglobulins by all four biopsy samples, and the two cell lines tested by these techniques. Newly synthesized labelled proteins were demonstrable in the culture medium within 1 hour of incubation.