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Leukocyte migration inhibition activity of nonimmune acute inflammatory pleural exudate
Abstract:
Material with leuckocyte migration inhibition (LMI) activity has been demonstrated in various types of nonimmunologically induced acute pleural inflammatory exudates. This activity is present in inflammatory cell-free exudate and appears to involved the deposition of fibrin around the migrating leukocyte, resulting in "cell-trapping." This is supported by the fact that removal or inhibition of fibrin formation leads to loss of exudate LMI activity. Both fibrinogen and complement as well as vitamin K-dependent clotting factors appear to be required for LMI activity. The mechanism involved in the LMI reaction and its significance in nonimmune and cell-mediated immune inflammation are discussed.
Insights
Leukocyte migration inhibition (LMI) activity in pleural exudates involves fibrin deposition, trapping leukocytes. Inhibiting fibrin formation abolishes this non-immune inflammatory response.
Area of Science:
- Inflammation and Immunology
- Hematology
- Biochemistry
Background:
- Leukocyte migration inhibition (LMI) activity is observed in acute pleural inflammatory exudates.
- This activity occurs in cell-free exudate and is linked to fibrin deposition around leukocytes, causing 'cell-trapping'.
Purpose of the Study:
- To investigate the mechanism of LMI activity in non-immunologically induced pleural inflammation.
- To determine the role of fibrin formation and other factors in LMI activity.
Main Methods:
- Analysis of inflammatory exudates for LMI activity.
- Experimental manipulation of fibrin formation (removal or inhibition).
- Assessment of the requirement for fibrinogen, complement, and vitamin K-dependent clotting factors.
Main Results:
- LMI activity was demonstrated in non-immunologically induced pleural exudates.
- Fibrin deposition around migrating leukocytes was identified as the cause of 'cell-trapping'.
- Removal or inhibition of fibrin formation led to the loss of LMI activity.
- Fibrinogen, complement, and vitamin K-dependent clotting factors were found to be necessary for LMI activity.
Conclusions:
- Fibrin deposition is a key mechanism underlying LMI activity in acute pleural inflammation.
- The LMI reaction plays a role in non-immune inflammatory processes.
- Understanding LMI mechanisms may offer insights into cell-mediated immune inflammation.
