The granuloma pouch: An in vivo model for pharmacokinetic and chemotherapeutic investigations. I. Biochemical and histological characterization

Abstract

The "granuloma pouch" model in rats was evaluated on the basis of biochemical, haematological and histological factors. Seven days after formation of the pouch following the intramuscular injection of air and a mixture of 1% croton oil in olive oil as an irritant, the pouch was filled by approximately 5 ml of haemorrhagic exudate. Biochemical assessment of the exudate revealed that its main characteristics were increased lactate dehydrogenase levels as well as increased alpha 2- and gamma-globulin fractions. Histological sections of the surrounding tissue showed a typical granulomatous inflammatory response. The granuloma pouch can therefore be characterized as a local, chronic inflammation caused by the creation of a body cavity. The biochemical data of the pouch exudate were compared with those of human wound fluid obtained after surgery; since the values were in very good agreement, it is assumed that the granuloma pouch model reflects the clinical situation in inflamed wound cavities following the extirpation of organs.

Rat Pneumonia and Soft-Tissue Infection Models for the Study of Acinetobacter baumannii Biology

“…After 7 days this resulted in an encapsulated "pouch" that was filled with an exudative fluid (pouch fluid), mimicking a subcutaneous abscess. This model has been well characterized (7,8). It is a dynamic model, as evidenced by the fact that neutrophils will migrate into the pouch in response to appropriate stimuli.…”

“…Complement and neutrophils are innate host defense factors known to be active in the soft-tissue infection model (7,8). Since various strains of Acinetobacter were variably cleared in this model, we hypothesized that complement is an important host factor in protecting against A. baumannii infection in vivo.…”

Intradermal air pouch leukocytosis as an in vivo test for nanoparticles

“…6 For a considerable time, the rodent air pouch model was assumed to reflect the clinical situation of healing wound cavities after extirpation of organs. 7 Thereafter came a period when it was recognized that this model is useful for the study of immune reactions, bone and cartilage breakdown, and also for drug testing. [8][9][10][11][12][13] In addition to cell infiltrations, the production of biological agents, eg, matrix metalloproteinases (MMPs), was studied in the pouch exudates.…”

“…15 Air pouch models were used to study mechanisms of action of drugs, pharmacokinetics, enzyme induction or inhibition, regional drug delivery, angiogenesis, and cell migration. 7,14,[16][17][18][19][20][21][22] Gradually, the mouse air pouch model became a standard test in pharmacological, immunological, and biomaterials research. [23][24][25][26][27] With the application of the mouse air pouch model, genetic factors, including those encoding cytokines, proteinases and other enzymes, and adhesion molecules were identified in inflammation; the combination with spontaneous gene deficiencies or gene knockout technology further enhanced insights into inflammatory processes.…”

IroN Functions as a Siderophore Receptor and Is a Urovirulence Factor in an Extraintestinal Pathogenic Isolate of Escherichia coli

“…To determine whether IroN contributes to virulence in an extraintestinal site of infection other than the urinary tract, dual infection (competition) experiments were performed with the rat granuloma pouch model, which mimics an intra-abdominal abscess (6). Three independent experiments were performed, in which a total of 20 rats were challenged with a mixed inoculum containing approximately 10 3 to 10 4 CFU of both CP9 (wild type) and its isogenic IroN-deficient derivative (CP82), and the ratio of CP9 to CP82 in granuloma pouch fluid was determined at 0, 3, 6, and 24 h. Although some animal-to-animal variability occurred, overall no consistent or statistically significant competitive advantage was observed for either strain (data not shown).…”