Abstract: In an embodiment, the invention provides an isolated population of exosomes comprising interleukin-27 (IL-27) or interleukin-35 (IL-35). In an embodiment, the invention also provides a method of preparing a population of exosomes comprising interleukin-27 (IL-27), the method comprising: (a) isolating CD19+B2 cells or B1a cells; (b) activating the isolated cells with a LPS or a BCR agonist to provide activated cells; and (c) isolating exosomes secreted from the activated cells. In an embodiment, the invention also provides a method of preparing a population of exosomes comprising interleukin-35 (IL-35), the method comprising: (a) isolating CD138+plasma cells; (b) activating the isolated cells with a LPS or a BCR agonist to provide activated cells; and (c) isolating exosomes secreted from the activated cells. Additional embodiments of the invention are as described.

Abstract: The present invention provides methods of treating and preventing uveitis in a subject using a single-domain antibody (sdAb), wherein the sdAb comprises the amino acid sequence as set forth in SEQ ID NO:1. In one aspect, the subject is a mammal such as a human. In another aspect, the sbAb is used in combination with one or more compounds. The uveitis treated by the invention can be sympathetic ophthalmia, birdshot retinochoroidopathy, Behcet's disease, Vogt-Koyanagi-Harada disease and ocular sarcoidosis.

Abstract: The invention is directed to an isolated population of mammal cells comprising about 75% or higher B-1a regula e PBS-treated tory cells expressing the cell surface inhibitory receptors lympho-cyte-activation gene 3 (LAG-3), programmed cell death protein 1 (PD-1), and C-X-C chemokine receptor type 4 (CXCR4), and secreting interleukin-27 (IL-27). The invention is also directed to methods of preparing and using the cell population to suppress the immune system and/or to treat or prevent diseases.