19 



Bone Destruction by 

 Multinucleated Giant Cells 



JAMES T. IRVINCrand CHESTER S. HANDELMAN, Harvard School 

 of Dental Medicine and For.s\th Dental Center, Boston. IVIassachusetts 



THE osteoclastic ability of foreign body giant cells was noted by 

 Bujard ( 1946 ) , who injected particles of ground-up bone under the 

 skin or into muscles and found them surrounded by giant cells which 

 behaved like osteoclasts. A little later Ham and Gordon (1952) 

 implanted dead autogenous bone into muscles and observed the 

 formation of typical osteoclasts around the implants. They con- 

 cluded that these cells did not need to arise from osteogenic cells 

 or from osteoblasts. Bujard considered that these osteoclasts could 

 arise from mesenchymatous cells that were in the "etat histocytaire." 

 In the present experiments a similar technique was used in the 

 investigation of several problems: (1) to determine whether these 

 giant cells had the same cytochemical properties as osteoclasts 

 found around bone in its normal position; (2) to study the effect 

 of chemical or biological alterations of implanted bone upon the 

 ability of these giant cells to resorb it; in the present paper, the 

 reaction with rachitic osteoid is described; ( 3 ) to determine whether 

 the osteoclasis of the devitalized bone implants was dependent on 

 the parathyroid glands. 



515 



