Nitric oxide-dependent neutrophil recruitment: role in nasal secretion

Leukotriene B4 (LTB4), an inflammatory mediator, is a potent chemoattractant for neutrophils that plays an important role in nasal secretion via release of elastase. Nitric oxide (NO) is an important modulator of leucocyte-endothelial cell interactions, endogenously produced in large quantities in the paranasal sinuses. To examine the role of NO in LTB4-stimulated nasal secretion. A newly-developed method for isolating and superfusing a nasal segment in dogs was used. Instillation of LTB4 into the nasal segment caused a time-dependent increase in the volume of airway fluid and in the recruitment of neutrophils. N(G)-nitro-L-arginine-methylester (L-NAME), an inhibitor of NO synthase, prevented LTB4-induced neutrophil recruitment and nasal secretion. These studies show that NO modulates LTB4-induced neutrophil recruitment and subsequent fluid secretion in the nose, and they suggest a therapeutic role for NO inhibitors in modulating neutrophil-dependent nasal secretion.     

LTB4和IL-5在AR病情发展中的作用

目的：探讨白三烯B4（LTB4）、白介素-5（IL-5）在变应性鼻炎（AR）病情发展中的作用。方法：通过检测不同病情AR患者外周血LTB4、IL-5含量情况。结果：AR重度组外周血LTB4、IL-5含量高于AR中度组（均P〈0.05）;AR中度组外周血LTB4、IL-5含量高于AR轻度组（均P〈0.05）;AR轻度组外周血LTB4、IL-5含量高于对照组。结论：AR患者体内高浓度的LTB4、IL-5对病情起了加剧、促进作用,LTB4与IL-5间可能存在某种正反馈机制。临床可通过检测AR患者外周血LTB4、IL-5的含量,作为评价AR病情严重程度与治疗效果的指标。     

Elevated expression of prostaglandin receptor and increased release of prostaglandin E2 maintain the survival of CD45RO+ T cells in the inflamed human pleural space

Throughout the body, the distribution and differentiation of T-cell subsets varies in a way that optimizes host responses. The role of activation-induced cell death (AICD) in altering the distribution of T-lymphocyte subsets at an immune or inflammatory sites has been unexplored. The objective of this study was to assess whether pleural macrophages modulate AICD of specific pleural T-lymphocyte subsets. We found that pleural T-lymphocytes spontaneously undergo apoptosis, which is associated to increased expression of both FAS and FAS ligand, to decreased expression of Bcl 2 and to caspase 8 and 3 activation. While pleural T lymphocytes were partly protected from apoptosis, autologous peripheral blood T lymphocytes increased their apoptosis when cultured with exudative pleural fluids. Pleural CD45RO(+) T cells, in comparison to pleural CD45RA(+) T cells, were more susceptible to apoptosis, but were preferentially protected by exudative pleural fluids. Pleural prostaglandin E 2 (PGE(2)) was implicated in protecting T-lymphocytes from apoptosis because exudative pleural T lymphocytes highly express PGE(2) receptors, and because exudative pleural fluid contained high concentrations of PGE(2). Activated pleural macrophages released PGE(2) and reduced the spontaneous apoptosis of pleural T lymphocytes and depletion of PGE(2) from pleural fluids decreased this protective effect. This study demonstrates that PGE(2), released in the pleural fluids following pleural macrophage activation, prolongs the survival of specific T-cell subsets, resulting in differentiation of the T-cell repertoire within the inflamed pleural space.     

Stromal cells differentially regulate neutrophil and lymphocyte recruitment through the endothelium

Stromal fibroblasts modify the initial recruitment of leucocytes by endothelial cells (EC), but their effects on subsequent transendothelial migration remain unclear. Here, EC and dermal or synovial fibroblasts were cultured on opposite surfaces of 3‐μm pore filters and incorporated in static or flow‐based migration assays. Fibroblasts had little effect on tumour necrosis factor‐α‐induced transendothelial migration of neutrophils, but tended to increase the efficiency of migration away from the endothelium. Surprisingly, similar close contact between EC and fibroblasts strongly reduced lymphocyte migration in static assays, and nearly abolished stable lymphocyte adhesion from flow. Fibroblasts did not alter endothelial surface expression of adhesion molecules or messenger RNA for chemokines. Inhibition of attachment did not occur when EC‐fibroblast contact was restricted by using 0·4‐μm pore filters, but under these conditions pre‐treatment with heparinase partially inhibited adhesion. In the 3‐μm pore co‐cultures, inhibition of metalloproteinase activity partially recovered lymphocyte adhesion, but addition of CXCL12 (SDF‐1α) to the endothelial surface did not. Hence, the ability of EC to present activating chemokines for lymphocytes may have been enzymatically inhibited by direct contact with fibroblasts. To avoid contact, we cultured EC and fibroblasts on separate 3‐μm pore filters one above the other. Here, fibroblasts promoted the transendothelial migration of lymphocytes. Fibroblasts generate CXCL12, but blockade of CXCL12 receptor had no effect on lymphocyte migration. While stromal cells can provide signal(s) promoting leucocyte migration away from the sub‐endothelial space, direct cell contact (which might occur in damaged tissue) may cause disruption of chemokine signalling, specifically inhibiting lymphocyte rather than neutrophil recruitment.     

Combined treatment with a CXCL12 analogue and antibiotics improves survival and neutrophil recruitment and function in murine sepsis

Previous studies demonstrated that the CXCL12 peptide analogue CTCE-0214 (CTCE) has beneficial effects in experimental sepsis induced by caecal ligation and puncture (CLP). We examined the hypothesis that CTCE recruits neutrophils (polymorphonuclear leucocytes; PMN) to the site of infection, enhances PMN function and improves survival of mice in CLP-induced sepsis with antibiotic treatment. Mice with sepsis (n = 15) were administered imipenem (25 mg/kg) and CTCE (10 mg/kg) subcutaneously versus vehicle control at designated intervals post-CLP. CTCE treatment increased PMN recruitment in CLP-induced sepsis, as evidenced by increased PMN in blood, by 2·4 ± 0·6 fold at 18 hr, 2·9 ± 0·6 fold at 24 hr, and in peritoneal fluid by 2·0 ± 0·2 fold at 24 hr versus vehicle control. CTCE treatment reduced bacterial invasion in blood [colony-forming units (CFU) decreased 77 ± 11%], peritoneal fluid (CFU decreased 78 ± 9%) and lung (CFU decreased 79 ± 8% versus CLP vehicle). The improved PMN recruitment and bacterial clearance correlated with reduced mortality with CTCE treatment (20% versus 67% vehicle controls). In vitro studies support the notion that CTCE augments PMN function by enhancing phagocytic activity (1·25 ± 0·02 fold), increasing intracellular production of reactive oxygen species (32 ± 4%) and improving bacterial killing (CFU decreased 27 ± 3%). These composite findings support the hypothesis that specific CXCL12 analogues with ancillary antibiotic treatment are beneficial in experimental sepsis, in part, by augmenting PMN recruitment and function.     

Eicosapentaenoic acid modulates neutrophil leukotriene B4 receptor expression in cystic fibrosis.

In patients with cystic fibrosis (CF), high intrapulmonary concentrations of the neutrophil chemotaxin leukotriene B4 (LTB4) are associated with specific reduction of LTB4-induced chemotaxis of circulating neutrophils. The chemotactic abnormality is partially corrected by dietary supplementation with eicosapentaenoic acid (EPA). LTB4-induced neutrophil chemotaxis is mediated by specific, high-affinity, cell surface LTB4 receptors. The hypotheses that neutrophil LTB4 receptors are down-regulated in CF, and that EPA normalizes receptor expression, were tested by measuring the number (Rmax) and affinity (Kd) of LTB4 receptors on neutrophils from eight CF patients before and after EPA (6 weeks of 2.7 g/day), and from nine normal individuals. High-affinity receptor Rmax was depressed in CF patients (0.6 +/- 0.2 x 10(4)/cell (mean +/- s.d.) versus 1.8 +/- 0.7 x 10(4)/cell in normals), but corrected to normal (2.0 +/- 1.9 x 10(4)/cell) after EPA. High-affinity receptor Kd was depressed in CF patients (0.4 +/- 0.3 nM versus 1.4 +/- 0.5 nM in normals), and also corrected to normal with EPA (1.4 +/- 1.2 nM). Low-affinity receptors were depressed, but did not change significantly with EPA. These results indicate that neutrophil responses in chronic inflammatory lung disease can be influenced directly by LTB4 receptor modulation, and that this effect of EPA predominates over alterations in neutrophil signal transduction in situations of chronic exposure to LTB4.     

LTB4 and BLT1 in inflammatory arthritis

Inflammatory arthritis, including rheumatoid arthritis (RA), is characterized by infiltration of inflammatory cells into the joints. Biological agents targeting TNF-α and IL-6 dramatically improve RA. However, some RA patients do not respond to current treatments and these broadly active upstream biological agents increase the risk of severe infection. Therefore, there remains a need for other effective and safe treatments for RA. Many studies have implicated that blockade of leukotriene B4 (LTB₄) and its high affinity receptor BLT1 dramatically suppress arthritis in animal models. In addition, levels of LTB₄ in serum, synovial fluid and synovial tissue are increased in RA patients compared to healthy donors or osteoarthritis patients. These data suggest that LTB₄ and BLT1 likely contribute to the pathogenesis of human RA. However, several clinical trials inhibiting BLT1 in RA were not successful. Our recent data revealed that LTB₄ is a key mediator in a complement, lipid, cytokine and chemokine cascade that first initiates and then sustains neutrophilic inflammation in inflammatory arthritis. These new mechanistic studies suggest novel ways to target the LTB₄-BLT1 pathway for the treatment of RA and other inflammatory diseases.     

Squamous cell carcinoma-derived G-CSF promotes tumor growth and metastasis in mice through neutrophil recruitment and tumor cell proliferation,associated with poor prognosis of the patients

Tumor-derived G-CSF is a well-known factor to aggravate disease progression in various types of cancers. In this study, we investigated a role of G-CSF in squamous cell carcinoma (SCC). High expression of G-CSF in the tumor tissues of esophageal SCC (ESCC) patients correlated with poor prognosis. Murine SCC NR-S1M cells produce considerable amount of G-CSF, which expression is correlated with its metastatic potentials. Deletion of G-CSF in NR-S1M cells mitigated tumor growth and metastasis to lymph node and lung of subcutaneous NR-S1M tumors in the mice. Mechanistically, G-CSF enhanced cell proliferation in autocrine manner in vitro, whereas in NR-S1M tumor-bearing mice, accumulation of plasma G-CSF was associated with expansion of peripheral neutrophils, which led to a decreased proportion of CD8⁺ T cells. Antibody depletion of neutrophils restored the number of CD8+ T cells and modestly suppressed tumor outgrowth, albeit no changes in distant metastasis. We propose that G-CSF produced by NR-S1M cells facilitates tumor progression in mice through bi-functional effects to promote neutrophil recruitment and tumor cell proliferation, which may render poor prognosis to the ESCC patients with high G-CSF expression.     

Netrin‐4 is upregulated in breast carcinoma effusions compared to corresponding solid tumors

We recently identified overexpression of the NTN4 gene in breast carcinoma effusions compared to primary carcinomas using gene‐expression arrays. The objective of this study was to validate this finding at protein level and analyze the clinical role of Netrin‐4 in breast carcinoma effusions. We additionally studied Netrin‐4 expression and its clinical relevance in Müllerian (ovarian, peritoneal, and tubal) carcinoma effusions. Sections from 82 breast carcinomas (53 effusions and 29 solid tumors) and 57 Müllerian carcinoma effusions were stained for Netrin‐4 using immunohistochemistry. Immunoreactivity was scored in carcinoma cells and analyzed for association with clinicopathologic parameters, including survival. In breast carcinoma, expression of Netrin‐4 was detected in carcinoma cells in 30/53 (57%) effusions compared to 3/29 (10%) solid tumors (P < 0.001). Netrin‐4 was further expressed in 31/57 (54%) Müllerian carcinoma effusions. No association was found between Netrin‐4 expression in breast or Müllerian carcinoma effusions and clinicopathologic parameters, including survival. Our data provide validation on protein level of upregulated Netrin‐4 expression in breast carcinoma effusions. The frequent expression of Netrin‐4 in Müllerian carcinoma effusions suggests a biological role for this molecule in metastases from gynecological malignancies. Netrin‐4 expression in effusions does not appear to be a predictor of disease outcome. Diagn. Cytopathol. 2011. © 2010 Wiley‐Liss, Inc.     

Early vasculitis in the mercuric chloride induced Brown Norway rat model is neutrophil independent

In the Brown Norway rat, mercuric chloride (HgCl2) induces an autoimmune syndrome characterized by necrotizing vasculitis, predominantly affecting the caecum, and a polyclonal B-cell response. The time course of vasculitis is biphasic, with an alphabeta T-cell independent phase occurring within 24 h, and a T-cell and neutrophil dependent phase, maximal at two weeks. The pathogenesis of the early phase of vasculitis is unclear, and this study aims to examine the role of neutrophils. Rat neutrophils were depleted using cyclophosphamide. RP3, an antirat neutrophil monoclonal antibody, inhibited neutrophil leucocytosis but did not deplete neutrophils. Vasculitis was induced by subcutaneous HgCl2 injection. Serial measurements of peripheral blood leucocyte count were made. Rats were killed after 24 or 72 h. The macroscopic appearance of the caecum was scored by an experienced observer, and samples taken for histological examination. Caecums were excised and myeloperoxidase, a marker enzyme for neutrophil infiltration, assayed. Cyclophosphamide induced marked neutropaenia whereas RP3 inhibited the neutrophilia observed after HgCl2 injection. Vasculitis was present in both treated and control animals, with no significant differences in macroscopic or microscopic scores between the groups. Tissue myeloperoxidase activity was low in all animals and did not differ significantly between groups. The data do not support a role for neutrophils in the initial pathogenesis of vasculitis in this model.     

MUC4 is upregulated in ovarian carcinoma effusions and differentiates carcinoma cells from mesothelial cells

Using gene expression arrays, we recently showed that MUC4 expression is significantly higher in ovarian/primary peritoneal serous carcinoma (OC/PPC) compared to diffuse peritoneal malignant mesothelioma (DMPM). In the present study, we analyzed the anatomic site-related expression of MUC4 in OC/PPC and studied its prognostic role. We additionally studied the ability of MUC4 to differentiate between OC/PPC and reactive mesothelial cells (RMC). OC/PPC effusions (n = 142) and benign reactive effusions (n = 10) were immunostained for MUC4 expression. Immunoreactivity was scored in carcinoma cells and RMC and was compared with tumor cell expression in 60 previously studied primary carcinomas and solid metastases and analyzed for association with clinicopathologic parameters, including survival. MUC4 was detected in carcinoma cells in 141/142 (99%) effusions, with comparable expression in peritoneal and pleural effusions. RMC were present in 72 malignant effusions and were MUC4-negative in all specimens, as well as in the 10 reactive effusions. MUC4 expression in carcinoma cells in effusions was significantly higher than in primary carcinomas and solid metastases (P < 0.001). Higher MUC4 expression was seen in tumors from older (>60 year) patients (P = 0.049). No association was found between MUC4 expression and other clinicopathologic parameters, including survival. MUC4 is universally expressed in OC/PPC effusions and is upregulated at this anatomic site compared to primary carcinomas and solid metastases. The data in the present study, together with our earlier report, show that MUC4 is an excellent marker for differentiating OC/PPC from both benign and malignant mesothelial cells.     

Induction of keratinocyte IL-8 expression and secretion by IgG autoantibodies as a novel mechanism of epidermal neutrophil recruitment in a pemphigus variant

A subset of pemphigus herpetiformis, a rare pemphigus variant, is characterized histopathologically by subcorneal acantholysis and neutrophilic infiltration. The mechanism of neutrophil infiltration is unknown, but chemokines such as IL-8 may play a role. We investigated the possible role of IL-8 in two such cases. Direct and indirect immunofluorescence studies demonstrated in vivo-bound and circulating IgG epithelial cell surface-binding autoantibodies, both predominated by IgG4 subclass. ELISA and immunoblotting studies revealed that the patients' IgG autoantibodies recognized recombinant desmoglein 1 but not desmoglein 3. Preadsorption of the patients' sera with recombinant desmoglein 1 completely removed the epidermal cell surface immunostaining. Significantly, immunohistochemistry demonstrated intense expression of IL-8, co-localized with in vivo-bound IgG, in the upper epidermis, where the acantholysis took place. Affinity-purified sera IgG from these two patients, a normal individual, and a pemphigus vulgaris patient containing desmoglein 1 autoantibodies, were incubated with normal human keratinocytes in vitro. Cells treated with these patients' IgG secreted a seven-to-nine-fold increase of IL-8 (30-37 pg/ml) compared with the controls (2-4 pg/ml) and expressed a higher intensity of cytoplasmic IL-8 staining. These data demonstrate a novel functional role for IL-8 in the pathogenesis of the neutrophil-dominant subset of pemphigus herpetiformis. The autoantibody-induced epidermal cell IL-8 expression may represent a novel mechanism of epidermal neutrophil recruitment.     

Immunomodulatory oligonucleotides inhibit neutrophil migration by decreasing the surface expression of interleukin-8 and leukotriene B4 receptors

Neutrophils play important roles in many inflammatory diseases. The migration of neutrophils to the inflammatory site is tightly regulated by specific chemokines, of which interleukin-8 (IL-8) and leukotriene B₄ (LTB₄) constitute key mediators by binding to the surface receptors CXCR1/2 and BLT1, respectively. Oligonucleotides (ODN) containing CpG motifs mediate potent immunomodulatory effects through binding to Toll-like receptor 9. So far, knowledge on how ODN can affect neutrophil migration during inflammation is lacking. This study demonstrates that several novel CpG ODN significantly down-regulate the surface expression of CXCR1/2 and BLT1. In addition, the ODN significantly blocked IL-8-induced and LTB₄-induced neutrophil migration in vitro, as well as leucocyte migration in vivo demonstrated in mice by intravital microscopy and in a model of airway inflammation. The down-regulation of CXCR1 is rapid, occurring 15 min after ODN stimulation, and can be mediated through an endosomally independent mechanism. Inhibition of the IL-8 and LTB₄ pathways may provide new opportunities of therapeutic intervention using ODN to reduce neutrophil infiltration during inflammation.     

Higher neutrophil infiltration mediated by osteopontin is a likely contributing factor to the increased susceptibility of females to alcoholic liver disease

Alcoholic liver disease (ALD) is a major public health problem in the United States and women are known to be more susceptible to ALD. However, the precise mechanism for increased susceptibility of females to ALD is not completely understood. The present study is based on the hypothesis that induction of osteopontin (OPN), a matricellular protein, is the likely contributing factor for higher neutrophil recruitment in females during alcoholic steatohepatitis (ASH). ASH was induced in male and female Sprague-Dawley rats by feeding them a Lieber-DeCarli diet containing ethanol (EtOH) for 6 weeks, followed by a single injection of lipopolysaccharide (LPS, 10 mg/kg, ip). Liver injury, measured by plasma transaminase elevations and confirmed by haematoxylin and eosin-stained liver sections, revealed approximately 25-fold higher liver injury in the female ASH model compared with the males. Although steatosis, necrosis, and neutrophil infiltration were evident in both male and female rats, hepatic neutrophilic necrotic foci were noted as early as 2 h after LPS injection in the EtOH-treated female rats. Hepatic neutrophil infiltration correlated with higher expression of cleaved (cOPN) and uncleaved OPN in the EtOH + LPS-treated female rats compared with the males. OPN secretion was localized predominantly in the biliary epithelium and females had significantly higher OPN mRNA than their male counterparts in the ASH model. The ability of OPN to attract neutrophils was further confirmed in vivo, in a peritonitis rat model, and by neutralizing OPN (nOPN) antibody experiments. Hepatic neutrophil infiltration was largely inhibited ( approximately 50%) by nOPN antibody. Flow cytometry experiments revealed OPN-mediated up-regulation of the CD11b neutrophil adhesion molecule. In conclusion, these data suggest that higher hepatic expression of OPN is the likely reason for higher and early hepatic neutrophil infiltration making females more susceptible to ALD during ASH.     

P-selectin requirement for neutrophil accumulation and injury in the direct passive Arthus reaction

The aim of this study was to investigate the role of P-selectin in the accumulation of neutrophils in the direct passive Arthus reaction in rat skin. Direct passive Arthus dermal reaction was induced in male Sprague-Dawley (SD) rats by a single i.v. injection of rat anti-sheep globulin (SG) 1 h before i.d. injection of SG antigen. Anti-P-selectin or irrelevant control antibody was given 1 h before rat anti-SG injection. Complement depletion was also performed in a separate group by pretreatment with cobra venom factor (CVF). In all groups dermal swelling was assessed 4 h after antigen challenge. Four hours after antigen challenge, rats treated with control antibody developed skin swelling (2.29 ± 0.47 mm), prominent complement deposition and neutrophil accumulation. This response was associated with local up-regulation of endothelial P-selectin. Pre-treatment with anti-P-selectin antibody 1 h before passive Arthus induction prevented skin swelling (0.29 ± 0.06 mm, P < 0.05, cf with control antibody treatment), neutrophil accumulation and up-regulation of endothelial P-selectin despite complement deposition. CVF treatment prevented complement deposition, neutrophil accumulation and skin swelling (0.13 ± 0.07 mm, P < 0.05, cf with saline treatment). However, endothelial P-selectin expression was still present. Inhibition of skin swelling and neutrophil accumulation in direct passive Arthus by functional inhibition of P-selectin suggest a pivotal role for this adhesion molecule in this inflammatory process. These results also suggest that multiple steps are involved in the evolution of direct passive Arthus, including both P-selectin expression and complement activation. However, while complement activation is essential for neutrophil accumulation and expression of dermal injury, P-selectin up-regulation initiated by antibody/antigen deposition occurs independently of complement activation.     

Enhanced formation and impaired degradation of neutrophil extracellular traps in dermatomyositis and polymyositis: a potential contributor to interstitial lung disease complications

Dermatomyositis (DM) and polymyosits (PM) are systemic autoimmune diseases whose pathogeneses remain unclear. Neutrophil extracellular traps (NETs) are reputed to play an important role in the pathogenesis of autoimmune diseases. This study tests the hypothesis that NETs may be pathogenic in DM/PM. Plasma samples from 97 DM/PM patients (72 DM, 25 PM) and 54 healthy controls were tested for the capacities to induce and degrade NETs. Plasma DNase I activity was tested to further explore possible reasons for the incomplete degradation of NETs. Results from 35 DM patients and seven PM patients with interstitial lung disease (ILD) were compared with results from DM/PM patients without ILD. Compared with control subjects, DM/PM patients exhibited a significantly enhanced capacity for inducing NETs, which was supported by elevated levels of plasma LL‐37 and circulating cell‐free DNA (cfDNA) in DM/PM. NETs degradation and DNase I activity were also decreased significantly in DM/PM patients and were correlated positively. Moreover, DM/PM patients with ILD exhibited the lowest NETs degradation in vitro due to the decrease in DNase I activity. DNase I activity in patients with anti‐Jo‐1 antibodies was significantly lower than in patients without. Glucocorticoid therapy seems to improve DNase I activity. Our findings demonstrate that excessively formed NETs cannot be degraded completely because of decreased DNase I activity in DM/PM patients, especially in patients with ILD, suggesting that abnormal regulation of NETs may be involved in the pathogenesis of DM/PM and could be one of the factors that initiate and aggravate ILD.     

Usefulness of Claudin 4 in the cytological diagnosis of serosal effusions

The identification of metastatic cells in serous effusions has prognostic and therapeutic implications, thus leading to a continuous search for improvement of the existing diagnostic procedures, including immunocytochemistry. To evaluate the usefulness of an antibody recognizing the tight junction-associated protein Claudin 4 in detecting metastatic tumor cells and in the differential with reactive and neoplastic mesothelium, we stained 345 cases of benign and neoplastic serous effusions obtained from pleura, peritoneum, and pericardium. Two-hundred and twenty-eight of 230 cases (99.1%) of epithelial metastasis of different origin were strongly stained by anti-Claudin 4, whereas all cases of reactive mesothelitis (78) and malignant mesothelioma (37) were negative. With the exception of a single case of ovarian carcinoma hypercalcemic-type, all tumors originating from the anatomical sites that most frequently metastasize to the serosae, including lung (61), breast (23), female genital tract (67), gastrointestinal tract (27), and peritoneum (6), were found to be positive. Claudin 4 was also extremely useful in detecting single-tumor cells dispersed among heavy inflammatory reaction. Because of its high sensitivity (99.1%) and specificity (100%), Claudin 4 might be used as an ideal "single-shot" marker for the identification of metastatic epithelial cells in serous effusions.     

Use of bioluminescence imaging to track neutrophil migration and its inhibition in experimental colitis

Inflammatory bowel disease (IBD) is associated with neutrophil infiltration into the mucosa and crypt abscesses. The chemokine interleukin (IL)‐8 [murine homologues (KC) and macrophage inflammatory protein (MIP)‐2] and its receptor CXCR2 are required for neutrophil recruitment; thus, blocking this engagement is a potential therapeutic strategy. In the present study, we developed a preclinical model of neutrophil migration suitable for investigating the biology of and testing new drugs that target neutrophil trafficking. Peritoneal exudate neutrophils from transgenic β‐actin‐luciferase mice were isolated 12 h after intraperitoneal injection with thioglycollate, and were assessed phenotypically and functionally. Exudate cells were injected intravenously into recipients with dextran sodium sulphate (DSS)‐induced colitis followed by bioluminescence imaging of whole‐body and ex vivo organs at 2, 4 and 16–22 h post‐transfer. Anti‐KC antibody or an isotype control were administered at 20 µg/mouse 1 h before transfer, followed by whole‐body and organ imaging 4 h post‐transfer. The peritoneal exudate consisted of 80% neutrophils, 39% of which were CXCR2⁺. In vitro migration towards KC was inhibited by anti‐KC. Ex vivo bioluminescent imaging showed that neutrophil trafficking into the colon of DSS recipients was inhibited by anti‐KC 4 h post‐cell transfer. In conclusion, this study describes a new approach for investigating neutrophil trafficking that can be used in preclinical studies to evaluate potential inhibitors of neutrophil recruitment.