MIP-1α-[CCL3] acting on the CCR1 receptor mediates neutrophil migration in immune inflammation via sequential release of TNF-α and LTB4

In the present study, we investigated the involvement of macrophage-inflammatory protein-lot (MIP-1 alpha)[CC chemokine ligand 3 (CCL3)], MIP-1 beta[CCL4], regulated on activation, normal T expressed and secreted (RANTES)[CCL5]. and CC chemokine receptors (CCRs) on neutrophil migration in murine immune inflammation. Previously, we showed that ovalbumin (OVA)-triggered neutrophil migration in immunized mice depends on the sequential release of tumor necrosis factor alpha (TNF-alpha) and leukotriene B-4 (LTB4). Herein, we show increased mRNA expression for MIP-1 alpha[CCL3], MIP-1 beta[CCL4], RANTES[CCL5], and CCR1 in peritoneal cells harvested from OVA-challenged, immunized mice, as well as MIP-1 alpha[CCL3] and RANTES[CCL5] but not MIP-1 beta[CCL4] proteins in the peritoneal exudates. OVA-induced neutrophil migration response was muted in immunized MIP-1 alpha[CCL3](-/-) mice, but it was not inhibited by treatment with antibodies against RANTES[CCL5] or MIP-1 beta[CCL4]. MIP-1 alpha[CCL3] mediated neutrophil migration in immunized mice through induction of TNF-alpha and LTB4 synthesis, as these mediators were detected in the exudates harvested from OVA-challenged immunized wild-type but not MIP-1 alpha[CCL3](-/-) mice; administration of MIP-1 alpha[CCL3] induced a dose-dependent neutrophil migration, which was inhibited by treatment with an anti-TNF-alpha antibody in TNF receptor I (p55(-/-))deficient mice or by MK 886 (a 5-lipoxygenase inhibitor); and MIP-1 alpha[CCL3] failed to induce LTB4 production in p55(-/-) mice. MIP-1 alpha[CCL3] used CCRI to promote neutrophil recruitment., as OVA or MIP-1 alpha[CCL3] failed to induce neutrophil migration in CCR1(-/-) mice, in contrast to CCR5(-/-) mice. In summary, we have demonstrated that neutrophil migration observed in this model of immune inflammation is mediated by MIP-1 alpha[CCL3], which via CCRI, induces the sequential release of TNF-alpha and LTB4. Therefore, whether a similar pathway mediates neutrophil migration in human immune-inflammatory diseases., the development of specific CCRI antagonists might have a therapeutic potential.