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Humanized double transgenic mice express both HLA-DR15 (the MHC gene linked to MS) and TCR.Ob1A12 from a multiple sclerosis patient (that recognizes MBP85-99 presented by HLA-DR15), yet they fail to develop autoimmune encephalomyelitis quickly, although 5-10% develop disease at 12 months. These mice were found to express large numbers of IL-10-secreting splenocytes as early as 4 weeks of age. These regulatory T cells appeared spontaneously without prior immunization with the autoantigen MBP85-99. They were of murine origin and had a cytokine secretion profile and surface phenotype similar to that reported for Tr1 cells. Notably, the frequency of disease appeared to increase at 14 months. The diseased mice had small spleens which averaged 47 mg, while the remaining non-diseased mice in our colony killed at ages 14-15 months had splenocytes that averaged 80 mg (ranging from 47-130 mg). Thus, the appearance of disease was associated with diminution in numbers of IL-10-secreting regulatory T cells with age.

Random amino acid copolymers used in the treatment of multiple sclerosis in man or experimental autoimmune encephalomyelitis (EAE) in mice [poly(Y,E,A,K)(n), known as Copaxone, and poly(Y,F,A,K)(n)] function at least in part by generation of IL-10–secreting regulatory T cells that mediate bystander immunosuppression. The mechanism through which these copolymers induce Tregs is unknown. To investigate this question, four previously described Vα3.2 Vβ14 T cell receptor (TCR) cDNAs, the dominant clonotype generated in splenocytes after immunization of SJL mice, that differed only in their CDR3 sequences were utilized to generate retrogenic mice. The high-level production of IL-10 as well as IL-5 and small amounts of the related cytokines IL-4 and IL-13 by CD4(+) T cells isolated from the splenocytes of these mice strongly suggests that the TCR itself encodes information for specific cytokine secretion. The proliferation and production of IL-10 by these Tregs was costimulated by activation of glucocorticoid-induced TNF receptor (GITR) (expressed at high levels by these cells) through its ligand GITRL. A mechanism for generation of cells with this specificity is proposed. Moreover, retrogenic mice expressing these Tregs were protected from induction of EAE by the appropriate autoantigen.

The study of amyotrophic lateral sclerosis (ALS) and potential interventions would be facilitated if motor axon degeneration could be more readily visualized. Here we demonstrate that stimulated Raman scattering (SRS) microscopy could be used to sensitively monitor peripheral nerve degeneration in ALS mouse models and ALS autopsy materials. Three-dimensional imaging of pre-symptomatic SOD1 mouse models and data processing by a correlation-based algorithm revealed that significant degeneration of peripheral nerves could be detected coincidentally with the earliest detectable signs of muscle denervation and preceded physiologically measurable motor function decline. We also found that peripheral degeneration was an early event in FUS as well as C9ORF72 repeat expansion models of ALS, and that serial imaging allowed long-term observation of disease progression and drug effects in living animals. Our study demonstrates that SRS imaging is a sensitive and quantitative means of measuring disease progression, greatly facilitating future studies of disease mechanisms and candidate therapeutics., Sensitive and label-free imaging methods to visualize nerve degeneration are currently lacking. Here authors show that stimulated Raman scattering (SRS) microscopy can be used to monitor peripheral nerve degeneration in mouse models of amyotrophic lateral sclerosis (ALS) and in postmortem tissue from ALS patients.