Dynamic deformation of migratory efferent lymph‐derived cells “trapped” in the inflammatory microcirculation

Abstract

The cellular immune response depends on the delivery of lymphocytes from the lymph node to the peripheral site of antigenic challenge. During their passage through the inflammatory microcirculaton, the migratory cells can become transiently immobilized or "trapped" in small caliber vessels. In this report, we used intravital microscopy and temporal area mapping to define the dynamic deformation of efferent lymph-derived mononuclear cells trapped in the systemic inflammatory microcirculation. Mononuclear cells obtained from the efferent lymph draining the oxazolone-stimulated microcirculation were labeled with fluorescent dye and reinjected into the feeding arterial circulation. Intravital video microscopy observed thousands of cells passing through the microcirculation; 35 cells were "trapped" in the oxazolone-stimulated microcirculation. Temporal area maps of the trapped cells demonstrated dramatic slowing and deformation. The cells were trapped in the microcirculation for a median of 8.90 sec (range 5-17 sec) prior to returning to the flow stream. During this period, the cells showed sustained movement associated with both antegrade locomotion (mean cell velocity = 7.92 microm/sec; range 1.16-14.23 microm/sec) and dynamic elongation (median cell length = 73.8 microm; range 58-144 microm). In contrast, efferent lymph-derived cells passing unimpeded through the microcirculation demonstrated rapid velocity (median velocity = 216 microm/sec) and spherical geometry (median diameter = 14.6 microm). Further, the membrane surface area of the "trapped" cells, calculated based on digital image morphometry and corrosion cast scanning electron microscopy, suggested that the fractional excess membrane of the cells in the efferent lymph was significantly greater than previous estimates of membrane excess. These data indicate that transient immobilization of efferent lymph-derived mononuclear cells in the systemic inflammatory microcirculation is rare. When "trapping" does occur, the shape changes and sustained cell movement facilitated by excess cell membrane may contribute to the return of the "trapped cells" into the flow stream.

Microangiectasias: Structural regulators of lymphocyte transmigration

“…The intravital videomicroscopy studies of the control microcirculation showed that Ͼ99% of the observed cells had flow velocities Ͼ2 m͞msec; no reproducible regions of lymphocyte slowing were observed (16). In contrast, the oxazolonestimulated microcirculation demonstrated reproducible lymphocyte slowing in focal regions of the microcirculation ( Fig.…”

Sepsis-3: new edition — old problems. analysis from the perspective of general pathology

“…Так, при СВ интенсивность системной альтерации должна быть сопоставима с локальным повреждением в очаге классического воспаления, чтобы реализовался феномен системной воспалительной микроциркуляции (системного микрососудистого васкулита). Таким образом, феномен воспалительной микроциркуляции является атрибутом очага классического воспаления [50], а на системном уровне -шокогенным проявлением СВ [3]. Проблема заключается в том, что однозначно идентифицировать СВ с помощью измерения уровня СВР можно только в ограниченном числе случаев, например при тысячекратных повышениях в крови некоторых цитокинов («цитокиновый шторм» -признак гиперергической фазы СВ).…”

Möglichkeiten und Grenzen der Mikrogefäßdarstellung

“…6 a und b). Zur besseren Kontrastierung können Farbstoffe i. v. appliziert werden, zur Verfolgung zum Beispiel von Lymphozyten, die in definierten Gefäßabschnitten markiert und resuspendiert werden [19]. Die wichtigste Einschränkung der Intravitalmikroskopie ist jedoch die limitierte Eindringtiefe.…”