Abnormal monocytes (figs. 145—147) 



The two cells shown in figures 145 and 146 

 are classed as abnormal because they are under- 

 going early autolysis. In the former there are 

 only early manifestations of cell breakdown, the 

 vacuolization in the region of the Hof has become 

 amorphous, and the remainder of the cytosome 

 has an atypical tinge of color. The concentra- 

 tion of basophilic bodies at the cell margin is 

 probably not indicative of abnormality. 



A somewhat later stage in autolysis is shown 

 in figure 146, in which the cytoplasm has taken 

 on an overall reddish color and there is a de- 

 creased color difference between nucleus and 

 cytosome. Otherwise the structural breakdown 

 has not been extensive. There is no indication 

 whether the nucleus will go in the direction of 

 lysis or of chromatin clumping. 



Abnormality has been expressed in still an- 

 other way (fig. 147). The orange spheres of 

 the Hof increased in size whereas ordinarily they 

 are relatively uniform. The increase might be 

 due either to an abnormal growth of a sphere or 

 to the coalescence of adjoining spheres accom- 

 panied by changes in the reticulum. Aside from 

 this one point there is very little indication that 

 the cell is abnormal. 



Technic artifacts (figs. 148, 149) 



Only one type of technic artifact has been 

 found thus far in monocytes — a squashing of the 

 cell when the smear is made. A squashed mono- 

 cyte is rarely identified with certainty. In fig- 

 ure 148 the large size and the indented nucleus 

 aided in the exclusion of other cells. The mono- 

 cytes, for some reason, were the only cells in tlie 

 slide from which figure 149 was taken that showed 

 fragility. This slide gave an excellent series of 

 stages from a slightly squashed monocyte to the 

 extreme condition shown in figure 149. Wlien 

 it reaches the last condition there is nothing by 

 which the squashed cell may be identified as a 

 monocyte. Its size so far exceeds the size of the 

 normal monocyte nucleus that it has very little 

 meaning. The significance of the configuration 

 of such cells has been discussed in mammalian 

 literature, where they are called basket cells and 

 disintegrating cells when they have the appear- 

 ance shown in figure 149. Osgood and Ash- 



worth (1937) in speaking of them say (p. 20), 

 "These cells are probably not artifacts made in 

 smearing but remnants of dead cells." 



Kracke and Carver (1937) mention (p. 84) 

 that in mammalian literature smudged cells have 

 been divided into two types: "It has been stated 

 that smudge forms are degenerating lymphocytes 

 and that basket cells . . . are degenerating 

 granulocytes. . . . Nevertheless, it seems more 

 probable that the smudge cell is an eaily stage 

 and the basket cell a late stage of the same 

 process. 



"Crushing and iiipturing of monocytes, neu- 

 trophils, eosinophils and basophils . . . occur 

 in improperly made smears, especially when too 

 mucli pressure is applied to the drop of blood. 

 These cellular remnants are found in various ab- 

 normal states where there is excessive destruc- 

 tion of leukocytes. In these cases their occur- 

 rence is probably the result of toxic agents or of 

 an increased fragility of the cellular elements." 

 This point of view is in agreement with our 

 opinion that the actual production of smudged 

 cells comes at the time the smear is made and that 

 it is not a record of in vivo degeneration of leuko- 

 cytes. The basis for this opinion is the conspic- 

 uous difference between smears made from the 

 same bird at the same time and also the fact that 

 large numbers of smudged cells often occur at 

 thinned-out portions of the smear where presum- 

 ably the pressure is greater. This point of view 

 is not in conflict with the idea that there are dif- 

 ferences in cell fragility and that increased fra- 

 gility may accompany diseased conditions. 



Osgood and Ashworth (1937) say (p. 20) 

 that, "One should not, however, make the error 

 of omitting to include the disintegrated cells in 

 the differential count as a large number of disin- 

 tegrated cells is strongly suggestive of a diag- 

 nosis of leukemia and failure to include them 

 may give an eri'oneous impression of the true 

 incidence of other cell types." 



We have not found at this Laboratory that the 

 presence of smudged cells aids in the diagnosis 

 of the avian leukosis complex, but it is agreed that 

 smudged cells can influence the differential count. 

 A good example is the slide from which figure 

 149 was made. Smudged monocyte nuclei simi- 

 lar to the one illustrated were found in abun- 

 dance; yet intact monocytes were scarce and were 

 actually fewer than the smudged nuclei. Should 

 they be counted? It has been our experience 



72 



