ORIGIN AND FATE OF OSTEOCLASTS 317 



Bassini ('72), Pomraer ('81), and Gegenbaur 3 concurred fully 

 with Kolliker's thesis; Ziegler ('78), Lewis ('13), and others have 

 rejected it. Morrison ('73), working under the inspiration of 

 Kolliker, likewise reported having observed intermediates (in 

 the number of nuclei?) between the osteoblast and osteoclast. 



An origin by osteoblastic fusion was inferred by Howell ('90). 

 It is, he argues, "plausible to think that the closely packed cells 

 might become forced to form a polykaryocyte and a number 

 of transitional steps [in size and number of nuclei?] can be seen 

 in sections . . . ." 



Bredichin ('67) held the giant-cells of normal and pathological 

 bone resorption to be transitional stages in the transformation 

 of bone tissue into marrow and granulation tissue ; in other words, 

 they are nothing more than liberated bone cells become multi- 

 nucleate. Murisier (75) and Ziegler (78) expressed a some- 

 what similar opinion, while Rindfleisch (72) was likewise 

 convinced from the study of giant-cell sarcomata that the poly- 

 karyocytes are bone cells 'which have become free and gone 

 over into a peculiar hypertrophic state. The proliferation of 

 bone cells was also noted by Morrison (73). According to 

 Lowe (79), the osteoclastic nuclei arise either from bone cells 

 or from inwandering leucocytes. 



Wegner (72) observed a close association between poly- 

 karyocytes and blood-vessels in pathological bone resorption. 

 He also maintains that normally the osteoclasts originate as 

 proliferations of the vessel wall. An intimate relation to blood- 

 vessels, although not in every case an actual origin from them, 

 has been emphasized as well by Morrison (73), Brodowski 

 (75), Maas (77), Schaffer ('88), Bidder ('06), and others. 



According to Kaczander ('82), giant-cells (osteoclasts?) form 

 from enlarged, liberated cartilage cells by coalescence. These 

 cartilage cells may be multinucleate while within their capsules. 

 This interpretation is modified by Geddes ('13), who considers 

 osteoclasts to be "hybrid syncytial masses composed of fused 

 cartilage cells containing osteoblasts." 



3 Cited by A. Bidder ('06). 



