Calibration methods for automated hematology instruments

Recent CAP survey data have documented marked improvement in the reproducibility of hematologic tests. The favorable outcome is attributable largely to the widespread use of automated whole-blood analyzers. Calibration variability, however, detracts from this enhanced precision, and there are clear indications that improvement is necessary. Primary calibration methods for hemoglobin, hematocrit and cell counting procedures are presented. The methods of applying these primary calibration methods to automated whole-blood analyzers are delineated. The use of both preserved reference blood and statistical control technics for the identification of calibration loss is described.

Human neoplastic and normal cells in tissue culture. I. Cell lines derived from malignant melanomas and normal melanocytes

Forty-six cell lines derived from 31 human melanomas obtained from 28 patients were cultured. Fourteen of 16 lines have produced malignant tumors when injected into nude (thymus-deficient) mice. Tumors in 5 of the nude mice metastasized to distant lymph nodes and/or to the lungs of the mouse host. Extreme variability from line to line was observed for doubling time (34 to 106 hr), plating efficiency (0-86%), and melanin production. All tested lines had type B glucose-6-phosphate dehydrogenase, thereby excluding HeLa cell contamination. HeLa cells have been grown for some time in our laboratory. Our results clearly demonstrated that HeLa cell contamination does not occur invariably in heteroploid lines growing in a laboratory simultaneously with Hela cells, provided that proper care is taken to avoid such occurrence. Multiple cell lines derived from the same tumor had identical phosphoglucomutase enzyme phenotype, which suggested a lack of significant cross-contamination between the lines. Four long-term cultures of normal human uveal embryo melanocytes have also been established and characterized. Although all produced melanin after reaching saturation density, they differed from the melanoma cells morphologically; they were flat, not refringent, and lacked piling up and plating ability. When melanoma cells were exposed to bromodeoxyuridine (BUDR) for long periods, a phenotypic change toward non-neoplastic characteristics was observed. Cells became flat and not refringent and, when injected into nude mice, tumors appeared after a long latent period. These changes were completely reversible in vitro and in vivo. The BUDR-treated cultures were undistinguishable from the untreated mother cultures after 2 to 3 passages. Lines derived from tumors in nude mice (obtained by injection of BUDR-treated cells) were again indistinguishable from the untreated mother line. Normal melanocytes were mostly euploid; all the melanoma cells were aneuploid. All 29 cell lines derived from 14 patients had an average chromosome number higher than 46. Detailed group-by-group chromosome analysis always showed an excess of C chromosomes, which suggested that hyperreduplication of one or more C chromosomes is a specific characteristic of human melanomas.

Ultrastructure of the lung in Loeffler's pneumonia

A case is presented fulfilling the diagnostic criteria of "Loeffler's eosinophilic pneumonia". No etiologic factors could be determined, and the chest roentgenogram returned to normal. Lung biopsy at the peak of the disease demonstrated an interstitial eosinophilic pneumonia without tissue necrosia or vasculitis. By electron microscopy, the alveolar capillary basement membranes were intact and exhibited no immune deposits. Normal appearing eosinophils were abundant in the alveolar capillaries, interstitium and alveolar spaces. Occasional eosinophils released their granules within the alveolar wall. Macrophages were increased in number in both the alveolar wall and alveolar spaces.