Editorial: Immunotherapy for Tumor in the Brain: Insights From—and For—Other Tumor Sites

Tumor immunotherapy has now shown its promise for many, its disappointments and failings for others. Going forward, brain tumor patients can both benefit and contribute.Tumor immunotherapy is steadily progressing. As experience accumulates, it is important to consider its generality. The reviews herein emphasize the brain’s place among other tumor sites. Two major topics are addressed.THE SITE: WHAT CAN WE EXPECT FROM IMMUNOTHERAPY WHEN THE TARGET IS IN THE BRAIN?Experience with immunotherapy for different targets in the brain, including tumor and also pathogens, is reviewed. Long-standing assumptions are confronted. The potential for beneficial responses is stressed.BRAIN TUMOR IMMUNOTHERAPY: WHAT HAVE WE LEARNED SO FAR?Clinical experience with brain tumor immunotherapy, from a variety of centers, is reviewed. Primary tumors, emphasizing glioblastoma, and brain metastases are each considered

Monoclonal antibodies in neuro-oncology: Getting past the blood-brain barrier

Monoclonal antibodies (mAbs) are used with increasing success against many tumors, but for brain tumors the blood-brain barrier (BBB) is a special concern. The BBB prevents antibody entry to the normal brain; however, its role in brain tumor therapy is more complex. The BBB is closest to normal at micro-tumor sites; its properties and importance change as the tumor grows. In this review, evolving insight into the role of the BBB is balanced against other factors that affect efficacy or interpretation when mAbs are used against brain tumor targets. As specific examples, glioblastoma multiforme (GBM), primary central nervous system lymphoma (PCNSL) and blood-borne metastases from breast cancer are discussed in the context of treatment, respectively, with the mAbs bevacizumab, rituximab and trastuzumab, each of which is already widely used against tumors outside the brain. It is suggested that success against brain tumors will require getting past the BBB in two senses: physically, to better attack brain tumor targets, and conceptually, to give equal attention to problems that are shared with other tumor sites

Molecular Specificity of Defined Types of Amacrine Synapse in Cat Retina

The inner plexiform layer of cat retina contains synaptic struc-tures belonging to 50 or more types of “identified ” neurons. To learn whether there are antigens confined to subsets of these synaptic structures, we raised monoclonal antibodies to homog-enates of neural retina. Binding patterns of these antibodies were visualized by the peroxidase-antiperoxidase method and studied in serial, ultrathin sections by electron microscopy. Four antibodies stained the synaptic varicosities of certain amacrine cells. Many of the stained varicosities formed reciprocal syn-apses with a rod bipolar axon terminal, but only about half of the reciprocal synapses associated with a rod bipolar were stained. Other stained varicosities formed synapses with cone bipolar axons, ganglion cell dendrites, and unstained amacrine processes. The patterns were essentially the same for each an-tibody and were not altered by staining with the antibodies tw