PMN Chemotactic Activity Research Articles

Thalidomide does not Affect Polymorphonuclear Leukocyte (PMN) Chemotaxis

Effects of thalidomide on PMN chemotactic activity were investigated in guineapigs. Thlidomide, 12.5 and 25mg/kg, was injected intraperitoneally for two days, and in vitro chemotaxis of cardiac blood PMNs to LPS-treated serum and casein sodium was evaluated using Boyden chamber techniques. Thalidomide revealed no significant suppression of locomotion of PMNs.It is suggested that the effect of thalidomide on erythema nodosum leprosum, an Arthus type reaction, is not caused by the reduced PMN chemotaxis in the peripheral blood.

Polymorphonuclear leukocyte function during otitis media.

Polymorphonuclear leukocyte (PMN) function was evaluated in children with serous (SOM) and mucoid otitis media (MOM) and in an experimental model of acute purulent otitis media due to Streptococcus pneumoniae using chinchillas. Twenty-three of 100 children with SOM or MOM had depressed peripheral blood PMN chemotactic, bactericidal or chemiluminescence activity. Depressed PMN chemotactic activity was observed in 17(18%) of 97 children. Children whose middle ear effusions cultured Hemophilus influenzae were more than twice as likely to have depressed PMN chemotactic activity as children whose effusions were sterile. Depressed PMN bactericidal activity was observed in seven (23%) of 30 children, and depressed PMN chemiluminescence activity was found in three (16%) of 19 children. Combined chemotactic and bactericidal dysfunction was observed in four (13%) of 30 children. All seven of the chinchillas with pneumococcal otitis media showed significantly depressed PMN chemotactic activity during the first week after inoculation, while only two of ten uninfected control chinchillas showed the same degree of chemotactic depression (P = .002). The association of H. influenzae and S. pneumoniae with depressed PMN function suggested that bacterial components of these microbes might have functional similarities. Both bacteria are surrounded by capsular polysaccharides which are known to persist in mammalian tissues for an extended period. It is possible that these or other components of H. influenzae and S. pneumoniae, or even host factors generated during middle ear infection and inflammation, impair the PMN response to middle ear infection resulting in delayed bacterial killing and persistent middle ear effusion.

Defective Polymorphonuclear Leukocyte Chemotaxis and Bactericidal Capacity in a Boy With Recurrent Pyogenic Infections

A 13-year-old boy with a history of recurrent pyogenic infections had abnormalities of polymorphonuclear leukocyte (PMN) function which probably accounted for his susceptibility to infection. PMN phagocytosis and nitroblue tetrazolium dye reduction were normal but glucose 14C oxidation was abnormally increased in resting cells. The patient's PMNs possessed decreased bactericidal activity against Staphylococcus aureus and Escherichia coli. Also documented were decreased PMN chemotactic activity and leukocyte accumulation in Rebuck skin windows. PMN random motility, PMN bone marrow reserve, PMN kinetics, lymphocyte blastogenesis, and delayed cutaneous hypersensitivity were normal. This patients represents another of the growing number of distinct granulocytopathies currently being recognized which may result in increased susceptibility to infection.

In vivo and in vitro studies on possible pathogenic mechanisms of Actinomyces viscosus

Actinomycotic infections are characterized by long-term inflammatory lesions containing large numbers of polymorphonuclear leukocytes (PMNs) and mononuclear cells. The pathogenic mechanisms involved in these lesions are not understood. Homogenates of Actinomyces viscosus (AVIS) induce an acute inflammatory response with a predominance of PMNs within 6 h after injection into the footpads of nonimmunized mice. These homogenates, when tested in vitro, contain potent chemotactic activity for human PMNs. In vitro chemotactic activity for human monocytes is weak but statistically significant (P less than 0.025). Doses of AVIS, which alone have little chemotactic activity, cause the generation of PMN chemotactic activity in fresh, but not complement-inactivated, serum. The injection of AVIS into the footpads of immunized mice induces an acute inflammatory response followed within 48 h by a mononuclear cell infiltrate, suggesting that factors affecting monocyte accumulation are generated by the immune host in response to challenge with the bacterial antigens. These findings indicate that the pathogenicity of the Actinomyces may result in part from (i) their direct chemotactic effect on PMNs, (ii) their cytotaxigenic effects on serum, and (iii) their ability to stimulate host immune cells to produce and release mediators of inflammation.

Generation of chemotactic factors in guinea pig serum via activation of the classical and alternate complement pathways

The characteristics of generation of PMN chemotactic factors by endotoxin and immune complexes have been studied in normal and C4-deficient guinea pig serum. Over a wide dosage range, both activating agents effectively interacted with C4-deficient serum to produce normal levels of chemotactic activity. The appearance of activity was blocked by EDTA or prior heating of the serum, but not by EGTA. The alternate pathway of complement activation, therefore, is capable of mediating efficient generation of chemotactic factors by endotoxin and immune complexes. In studies of the kinetics of generation of chemotactic factors, it was shown that activation of the alternate complement pathway resulted in an initial latent period with subsequent rapid appearance of activity, while classical C142 pathway activation led to very rapid early generation of chemotactic activity. The PMN chemotactic activity generated by either endotoxin or immune complexes resides in two distinct low molecular weight factors (17,000 and 10,000). These factors have been identified as two different C5 cleavage products.

Polymorphonuclear Leukocyte Chemotactic Activity in Rabbit Serum and Guinea Pig Serum Treated with Immune Complexes: Evidence for C5a as the Major Chemotactic Factor

A number of polymorphonuclear leukocyte (PMN) chemotactic factors derived from complement components have been described. We sought to determine which of these factors accounted for the majority of PMN chemotactic activity in rabbit serum and guinea pig serum treated with preformed immune complexes. Normal rabbit sera, guinea pig sera, or rabbit sera deficient in C6 were treated with homologous antibovine serum-albumin-bovine serum-albumin complexes. Sera so treated contained one major PMN chemotactic factor which was heat-stable (56 C for 30 min), had a molecular weight of approximately 15,000, and did not require the presence of C6 for its generation. This factor appears to be analogous to C5a.