1150 



PHYSIOLOGY 



Polymorphonuclear (polyrmclear, finely 

 granular oxyphile. neutrophile, or 

 amphophile cell). 



Eosinophile (coarsely granular oxyphile, 

 macroxycyte). 



Lymphocyte (? of two types). 

 Plasma-cell (? histogenous). 

 Endothelioid leucocyte (mononuclear 



leucocyte, hyaline cell (in part), * epi- 



thelioid cell '(in part). 



Connective tissue wandering cell (in- 

 cluding clasmatocyte). 



Originating in adult mammals from 

 the bone marrow, and migrating 

 from the blood into the inflam- 

 matory area. 



Originating from lymphoid tissue and 

 from vascular and other endothelia 

 respectively ; present in inflamed 

 area either by migration from blood 

 or as result of local proliferation. 



Originating locally as result of tissue 

 proliferation. 



The part played by each of these forms is still to a large extent 

 the subject of discussion. There is no doubt that in all active 

 inflammations the polymorphonuclear leucocyte is the form which 

 is attracted first and in largest numbers to the seat of injury. It 

 is the characteristic cell from which pus is formed, and is actively 

 phagocytic. It has nothing to do with the regeneration of the 

 destroyed tissue. The eosinophile corpuscle is also present at an 

 early stage around the inflammatory focus, but is never present in 

 numbers at all comparable with those of the polymorphonuclear 

 leucocyte. It is especially abundant in chronic inflammations of 

 certain tissues, such as the skin. According to Kant hack and Hardy, 

 these cells discharge their granules into the surrounding fluid, render- 

 ing this fluid toxic for bacteria. Although later observations have 

 failed to confirm these views, no other satisfactory explanation has 

 been given as to the part played by these cells. They are rarely seen 

 to ingest bacteria and therefore cannot be spoken of as phagocytic. 

 The lymphocyte predominates in certain chronic inflammations, 

 especially in those caused by the tubercle bacillus. They do not ingest 

 bacteria. The histogenous wandering cells appear in the inflam- 

 matory area at a later period than the polymorphonuclear and eosino- 

 phile cells. They are actively phagocytic and are motile. As a rule 

 their phagocytic properties are exerted, not on bacteria, but on other 

 cells and cell-debris. After an acute inflammation their chief office 

 is to clear away the remains of the polymorphonuclear leucocytes and 

 dead tissues so as to prepare the way for subsequent regeneration. It 

 is possible that these cells may take a part in the formation of new 

 connective tissue. They are indistinguishable from the immature 

 form of connective tissue-cells. It is therefore difficult to be certain 

 whether the wandering and the fixed connective-tissue corpuscles are 

 of identical or of different origin. Metchnikoff speaks of these cells as 

 macrophages, to distinguish them from the polymorphonuclear type, 

 which he terms microphages. 



We thus see that several types of the wandering cells of meso- 

 blastic origin which take part in inflammation do not exert active 



