[Therapeutic effect of nivolumab on non-small-cell lung cancer patients with brain metastases: a retrospective study]

Objective: To preliminarily explore the treatment effect of nivolumab on Chinese non-small-cell lung cancer (NSCLC) patients with brain metastases, and further enrich the evidences of programmed death-ligand 1 (PD-1) monoclonal antibody in the treatment of NSCLC patients with brain metastases. Methods: The clinical and pathological data of 22 NSCLC patients with brain metastases treated with nivolumab were collected. The electronic imaging data were collected to confirm the treatment effect and time point of disease progression, and the survival data of the patients were obtained through follow-up. Results: Twenty-one patients were evaluated for the intracranial treatment effect. The intracerebral objective response rate (IORR) was 28.6%, the intracranial disease control rate (IDCR) was 47.6%. The median intracranial progression-free-survival (iPFS) of all the 22 patients was 5.2 months. Both the 1-year and 2-year survival rates were 56.7%. Conclusions: The treatment effect of PD-1 monoclonal antibody on NSCLC patients with brain metastases is similar as those without brain metastases.

Autocrine action of IL-10 suppresses proinflammatory mediators and inflammation in the HSV-1-infected cornea

We investigated whether IL-10 produced endogenously would influence the development of HSV-1-induced acute corneal disease. Murine corneal epithelial cells and fibroblasts cultured in vitro expressed IL-10 mRNA and protein constitutively and also IL-10 receptors. Inclusion of IL-10 neutralizing antibody in the culture medium significantly (p<0.05) enhanced TNF-alpha-induced IL-6 and MIP-2 production by both corneal cell types. Endogenous IL-10 synthesis, which also occurred in vivo, was not modulated by Herpes virus infection or by depletion of neutrophils or natural killer cells. Antibody to IL-10 given locally at the time of HSV-1 intracorneal infection was associated with significantly (p<0.05) enhanced production of IL-6, MIP-2, and MIP-1alpha, increased neutrophil infiltration, and more extensive corneal disease. Similarly, mice with a disrupted IL-10 gene developed more severe corneal disease than wild-type controls. Collectively, these observations suggest that locally produced IL-10 can act in an autocrine/paracrine fashion to down-regulate the production of proinflammatory mediators and thus limit corneal inflammation.

Gene structure and promoter function of murine Munc18-2, a nonneuronal exocytic Sec1 homolog

Sec1 family proteins are regulators of diverse exocytic processes, from yeast to man. Three mammalian homologues, Munc18-1, -2, and -3 have been described. We have studied the structure and expression of the mouse Munc18-2 gene. The Munc18-2 gene comprises 19 exons whose sizes range from 50 to 158 bp, with a total gene size of approximately 11 kb. A single transcript of 2.1 kb is expressed in multiple non-neuronal murine tissues. Munc18-2 has a striking resemblance to Munc18-1 in structure despite only 60% sequence identity, suggesting a recent gene duplication event. Analysis of the region upstream of the transcription start site shows that Munc18-2 has a TATA-less promoter, with a consensus initiator (Inr) sequence at the start of transcription, several Sp1 binding sites, and strong promoter activity in RBL-2H3 mast cells. The region from +5 to -430 is more active than +5 to -800, suggesting upstream repressor elements.

Role of MIP-2 in neutrophil migration and tissue injury in the herpes simplex virus-1-infected cornea

PURPOSE

Neutrophils are the most prominent cell type to migrate initially into the herpes simplex virus type 1 (HSV-1)-infected murine cornea. The role the C-X-C chemokines macrophage inflammatory protein (MIP)-2 and KC play in promoting this response was investigated.

METHODS

MIP-2 and KC were quantitated by enzyme-linked immunosorbent assay. Neutralization of endogenous MIP-2 and KC was achieved by subconjunctival inoculation of the appropriate antibody. Infected corneas were examined immunohistochemically for infiltrating leukocytes and assayed for myeloperoxidase activity using the dye o-dianisidine. Depletion of neutrophils and natural killer cells was accomplished by intraperitoneal administration of RB6-8C5 and asialo GM1 antibodies.

RESULTS

Herpes simplex virus type 1, when introduced intracorneally, stimulated the production of MIP-2 and KC, with peak synthesis occurring 48 hours after infection. Dose-response studies showed that exogenous MIP-2 was three to four times more potent than KC in attracting neutrophils as assessed by myeloperoxidase assay and immunohistochemical staining. Subconjunctival administration of neutralizing antibody to MIP-2 resulted in a sharp decrease in neutrophil infiltration and significantly reduced corneal opacity scores. In contrast, in vivo treatment with neutralizing antibody to KC did not suppress ocular inflammation. Additional studies indicated that MIP-2 and KC could be made by corneal epithelial cells and that production was promoted by interleukin (IL)-1. In vivo depletion of neutrophils sharply reduced MIP-2 levels but did not affect KC levels.

CONCLUSIONS

Collectively, the results suggest that MIP-2 is the major chemokine that attracts neutrophils into the HSV-1 infected cornea, where the cells directly or indirectly cause tissue injury. Resident corneal cells and inflammatory cells contribute to MIP-2 synthesis, whereas KC production seems to be confined largely to corneal cells.

Chemokine synthesis in the HSV-1-infected cornea and its suppression by interleukin-10

Herpes simplex virus type 1 (HSV-1) infection of the murine cornea results in a tissue-destructive inflammatory response. In this study we show that virus infection induces the synthesis of macrophage inflammatory protein-2 (MIP-2), MIP-1alpha, and monocyte chemoattractant protein-1 (MCP-1). However, only the production of MIP-2 and MIP-1alpha coincided with the influx of leukocytes into the cornea. IL-10 treatment markedly suppressed chemokine message and protein synthesis in vivo. Local administration of IL-10 also dramatically reduced the number of T cells and neutrophils migrating into the cornea and suppressed the severity of corneal disease. The inflammatory response could also be suppressed by the passive transfer of neutralizing antibody to MIP-1alpha but not MCP-1. We conclude that local IL-10 administration can suppress chemokine synthesis, thereby ameliorating corneal disease. Furthermore, our results indicate that MIP-1alpha plays a major role in herpes stromal keratitis development, whereas MCP-1 does not.

Protective antibody therapy is associated with reduced chemokine transcripts in herpes simplex virus type 1 corneal infection

Herpes simplex virus type 1 (HSV-1) infection on the murine cornea induces an intense inflammatory response which can lead to blindness. This disease, known as herpes stromal keratitis, can be prevented by the timely passive transfer of monoclonal antibody specific for viral glycoprotein D (gD). Precisely how antibody treatment prevents excessive corneal inflammation is not known. In this study we investigated whether chemokine mRNA expression is inhibited by antibody treatment. Total cellular RNAs isolated from normal corneas and at various times after virus infection were analyzed via reverse transcription-PCR for mRNA coding for seven different chemokines. Constitutive levels of IP-10, KC, MIP-2, MCP-1, MIP-1 beta, and RANTES mRNA were detected in uninfected corneas of BALB/c mice. When the cornea was mechanically traumatized, message for all six chemokines was transiently elevated above constitutive levels. In contrast, HSV-1 infection resulted in prolonged enhanced chemokine message expression. The kinetics of mRNA accumulation was distinctive for each chemokine analyzed. MIP-1 alpha message, not detected constitutively, was not evident until day 7 postinfection. Administration of anti-HSV gD monoclonal antibody 1 day after infection was associated with reduced message for MIP-2, MCP-1, MIP-1 alpha, and MIP-1 beta. IP-10, KC, and RANTES messages were not altered. Collectively, our results suggest that anti-gD treatment may protect, at least in part, by inhibiting production of chemokines believed to promote inflammation.