Primary vitreoretinal lymphoma (PVRL), also known as primary intraocular lymphoma, is a rare malignancy typically classified as a diffuse large B-cell lymphoma and most frequently develops in elderly populations. PVRL commonly masquerades as posterior uveitis and has a unique tropism for the retina and central nervous system (CNS). Over 15% of primary CNS lymphoma patients develop intraocular lymphoma, usually occurring in the retina and/or vitreous. Conversely, 65%–90% of PVRL patients develop CNS lymphoma. Consequently, PVRL is often fatal because of ultimate CNS association. Current PVRL animal models are limited and require further development. Typical clinical findings include vitreous cellular infiltration (lymphoma and inflammatory cells) and subretinal tumor infiltration as determined using dilated fundoscopy, fluorescent angiography, and optical coherent tomography. Currently, PVRL is most often diagnosed using both histology to identify lymphoma cells in the vitreous or retina and immunohistochemistry to indicate monoclonality. Additional adjuncts in diagnosing PVRL exist, including elevation of interleukin-10 levels in ocular fluids and detection of IgH or T-cell receptor gene rearrangements in malignant cells. The optimal therapy for PVRL is not defined and requires the combined effort of oncologists and ophthalmologists. PVRL is sensitive to radiation therapy and exhibits high responsiveness to intravitreal methotrexate or rituximab. Although systemic chemotherapy alone can result in high response rates in patients with PVRL, there is a high relapse rate. Because of the disease rarity, international, multicenter, collaborative efforts are required to better understand the biology and pathogenesis of PVRL as well as to define both diagnostic markers and optimal therapies.

CD4+ T cells control the effector function, memory, and maintenance of CD8+ T cells. Paradoxically, we found that absence of CD4+ T cells enhanced adoptive immunotherapy of cancer when using CD8+ T cells directed against a persisting tumor/self-Ag. However, adoptive transfer of CD4+CD25− Th cells (Th cells) with tumor/self-reactive CD8+ T cells and vaccination into CD4+ T cell-deficient hosts induced autoimmunity and regression of established melanoma. Transfer of CD4+ T cells that contained a mixture of Th and CD4+CD25+ T regulatory cells (Treg cells) or Treg cells alone prevented effective adoptive immunotherapy. Maintenance of CD8+ T cell numbers and function was dependent on Th cells that were capable of IL-2 production because therapy failed when Th cells were derived from IL-2−/− mice. These findings reveal that Th cells can help break tolerance to a persisting self-Ag and treat established tumors through an IL-2-dependent mechanism, but requires simultaneous absence of naturally occurring Treg cells to be effective.

Summary Rapamycin increases lifespan in mice, but whether this represents merely inhibition of lethal neoplastic diseases, or an overall slowing in multiple aspects of aging is currently unclear. We report here that many forms of age-dependent change, including alterations in heart, liver, adrenal glands, endometrium, and tendon, as well as age-dependent decline in spontaneous activity, occur more slowly in rapamycin-treated mice, suggesting strongly that rapamycin retards multiple aspects of aging in mice, in addition to any beneficial effects it may have on neoplastic disease. We also note, however, that mice treated with rapamycin starting at 9 months of age have significantly higher incidence of testicular degeneration and cataracts; harmful effects of this kind will guide further studies on timing, dosage, and tissue-specific actions of rapamycin relevant to the development of clinically useful inhibitors of TOR action.