Effects of different sample preparations on enumeration of large granular lymphocytes (LGLs), and demonstration of a sex difference of LGLs.
Peripheral natural killer (NK) cells were identified by their morphologic appearance as large granular lymphocytes (LGLs) in a cytocentrifuged or spun blood film but not in thin wedge blood film. The authors studied the effect of different methods of sample preparation and staining on the enumeration of peripheral human LGLs as a routine test. In the blood film made from anticoagulated venous blood, LGLs were scattered in a field and sometimes deformed by compression of erythrocytes. In a blood film made from mononuclear cells, LGLs were shrunken, rendering it difficult to always identify cytoplasmic granules. In contrast, LGLs were easily and accurately identified in a blood film made from leukocyte-rich plasma, displaying none of the above artifacts. As well, the percentage of LGLs obtained was similar to that obtained from a blood film made from anticoagulated venous blood. In addition, May-Grünwald-Giemsa (MGG) stained azurophilic granules more clearly than did Giemsa above. As a result of these observations, a blood film that was made from leukocyte-rich plasma and that was stained by MGG was considered to be most suitable for the routine enumeration of LGL. Using this method, the authors found a significant correlation between the percentages of LGLs and Leu-7+ cells in the same subjects (r = 0.71; n = 22; P less than 0.001) and also a significant sex difference in the percentages of peripheral LGLs, which were significantly lower in women (17.0 +/- 3.6%; n = 35; P less than 0.05) than in men (19.5 +/- 5.3%; n = 20). Furthermore, the percentage of LGLs with abundant cytoplasmic granules, which might have greater NK activity, was also significantly lower in women (15.9 +/- 3.1%; n = 35; P less than 0.01) than in men (17.9 +/- 4.0%; n = 20).
Iwatani
Y
Y
Department of Laboratory Medicine, Osaka University Medical School, Japan.
Amino
N
N
Kabutomori
O
O
Tamaki
H
H
Aozasa
M
M
Motoi
S
S
Miyai
K
K
D000328:Adult; D005260:Female; D006801:Humans; D007694:Killer Cells, Natural / Q000166:cytology*; D007958:Leukocyte Count / Q000379:methods*; D008297:Male; D012727:Sex Characteristics; D013194:Staining and Labeling