B7-H1, a recently described member of the B7 family of costimulatory molecules, is thought to be involved in the regulation of cellular and humoral immune responses through the PD-1 receptor on activated T and B cells. We report here that, except for cells of the macrophage lineage, normal human tissues do not express B7-H1. In contrast, B7-H1 is abundant in human carcinomas of lung, ovary and colon and in melanomas. The pro-inflammatory cytokine interferon-gamma upregulates B7-H1 on the surface of tumor cell lines. Cancer cell-associated B7-H1 increases apoptosis of antigen-specific human T-cell clones in vitro, and the apoptotic effect of B7-H1 is mediated largely by one or more receptors other than PD-1. In addition, expression of B7-H1 on mouse P815 tumor increases apoptosis of activated tumor-reactive T cells and promotes the growth of highly immunogenic B7-1(+) tumors in vivo. These findings have implications for the design of T cell-based cancer immunotherapy.

No abstract

No abstract

Autoantibodies have defined two paraneoplastic visual disorders related to small-cell lung carcinoma: retinopathy ("CAR"-IgG [23kDa, recoverin]) and optic neuritis collapsin response-mediated protein 5 (CRMP-5-IgG [62kDa]). Among 16 patients with CRMP-5-IgG and optic neuritis (aged 52-74 years; all smokers, 9 women), we documented coexisting retinitis in 5. None had CAR-IgG. Fifteen had subacute vision loss, swollen optic discs, and field defects. Vascular leakage was evident at and remote from the disc; 5/5 tested had abnormal electroretinograms. Nine had striking vitreous cells. Vitrectomy showed reactive lymphocytosis (4/4), predominantly CD4(+) (1/1). Most patients had multifocal neurological accompaniments. Cerebrospinal fluid contained lymphocytes (7-32), elevated protein, multiple oligoclonal immunoglobulin bands, and CRMP-5-IgG. Three patients superficially resembled Devic's disease at presentation. One autopsied patient had predominantly CD8(+) T lymphocytes infiltrating optic nerve and spinal cord. Eleven patients had confirmed small-cell carcinoma; 1 had imaging evidence of lung cancer; 3 had renal or thyroid carcinoma. Full-length CRMP-5 protein was identified in normal retina and optic nerve by Western blot analyses. Photoreceptor cells, retinal ganglion cells, and nerve fibers exhibited CRMP-5-specific immunoreactivity. In summary, CRMP-5-IgG defines a paraneoplastic ophthalmological entity of combined optic neuritis and retinitis with vitreous inflammatory cells. Positive serology obviates the need for vitreous biopsy and expedites the search for cancer.

Malignant melanoma presents a substantial clinical challenge. Current diagnostic methods are limited in their ability to diagnose early disease and accurately predict individual risk of disease progression and outcome. The lack of adequate approaches to properly define disease subgroups precludes rational treatment design and selection. Better tools are urgently needed to provide more accurate