BACKGROUNDType 1 diabetes is a chronic autoimmune disease that leads to destruction of insulinproducing beta cells and dependence on exogenous insulin for survival. Some interventions have delayed the loss of insulin production in patients with type 1 diabetes, but interventions that might affect clinical progression before diagnosis are needed. METHODSWe conducted a phase 2, randomized, placebo-controlled, double-blind trial of teplizumab (an Fc receptor-nonbinding anti-CD3 monoclonal antibody) involving relatives of patients with type 1 diabetes who did not have diabetes but were at high risk for development of clinical disease. Patients were randomly assigned to a single 14-day course of teplizumab or placebo, and follow-up for progression to clinical type 1 diabetes was performed with the use of oral glucose-tolerance tests at 6-month intervals. RESULTSA total of 76 participants (55 [72%] of whom were ≤18 years of age) underwent randomization -44 to the teplizumab group and 32 to the placebo group. The median time to the diagnosis of type 1 diabetes was 48.4 months in the teplizumab group and 24.4 months in the placebo group; the disease was diagnosed in 19 (43%) of the participants who received teplizumab and in 23 (72%) of those who received placebo. The hazard ratio for the diagnosis of type 1 diabetes (teplizumab vs. placebo) was 0.41 (95% confidence interval, 0.22 to 0.78; P = 0.006 by adjusted Cox proportional-hazards model). The annualized rates of diagnosis of diabetes were 14.9% per year in the teplizumab group and 35.9% per year in the placebo group. There were expected adverse events of rash and transient lymphopenia. TIGIT+KLRG1+CD8+ T cells were more common in the teplizumab group than in the placebo group. Among the participants who were HLA-DR3-negative, HLA-DR4positive, or anti-zinc transporter 8 antibody-negative, fewer participants in the teplizumab group than in the placebo group had diabetes diagnosed. CONCLUSIONSTeplizumab delayed progression to clinical type 1 diabetes in high-risk participants.

BACKGROUND. Type 1 diabetes (T1D) results from destruction of pancreatic β cells by autoreactive effector T cells. We hypothesized that the immunomodulatory drug alefacept would result in targeted quantitative and qualitative changes in effector T cells and prolonged preservation of endogenous insulin secretion by the remaining β cells in patients with newly diagnosed T1D.METHODS. In a multicenter, randomized, double-blind, placebo-controlled trial, we compared alefacept (two 12-week courses of 15 mg/wk i.m., separated by a 12-week pause) with placebo in patients with recent onset of T1D. Endpoints were assessed at 24 months and included meal-stimulated C-peptide AUC, insulin use, hypoglycemic events, and immunologic responses.RESULTS. A total of 49 patients were enrolled. At 24 months, or 15 months after the last dose of alefacept, both the 4-hour and the 2-hour C-peptide AUCs were significantly greater in the treatment group than in the control group (P = 0.002 and 0.015, respectively). Exogenous insulin requirements were lower (P = 0.002) and rates of major hypoglycemic events were about 50% reduced (P < 0.001) in the alefacept group compared with placebo at 24 months. There was no apparent betweengroup difference in glycemic control or adverse events. Alefacept treatment depleted CD4 + and CD8 + central memory T cells (Tcm) and effector memory T cells (Tem) (P < 0.01), preserved Tregs, increased the ratios of Treg to Tem and Tcm (P < 0.01), and increased the percentage of PD-1 + CD4+ Tem and Tcm (P < 0.01).CONCLUSIONS. In patients with newly diagnosed T1D, two 12-week courses of alefacept preserved C-peptide secretion, reduced insulin use and hypoglycemic events, and induced favorable immunologic profiles at 24 months, well over 1 year after cessation of therapy.TRIAL REGISTRATION. https://clinicaltrials.gov/ NCT00965458.FUNDING. NIH and Astellas.

Barriers to the use of islet transplantation as a practical treatment for diabetes include the limited number of available donor pancreata. This project was designed to determine whether the size of the islet could influence the success rate of islet transplantations in rats. Islets from adult rats were divided into two groups containing small (diameter Ͻ125 m) or large (diameter Ͼ150 m) islets. An average pancreas yielded three times more small islets than large. Smaller islets were ϳ20% more viable, with large islets containing a scattered pattern of necrotic and apoptotic cells or central core cell death. Small islets in culture consumed twice as much oxygen as large islets when normalized for the same islet equivalents. In static incubation, small islets released three times more insulin under basal conditions than did large islets. During exposure to high glucose conditions, the small islets released four times more insulin than the same islet equivalencies of large islets, and five times more insulin was released by the small islets in response to glucose and depolarization with K ϩ . Most importantly, the small islets were far superior to large islets when transplanted into diabetic animals. When marginal islet equivalencies were used for renal subcapsular transplantation, large islets failed to produce euglycemia in any recipient rats, whereas small islets were successful 80% of the time. The results indicate that small islets are superior to large islets in in vitro testing and for transplantation into the kidney capsule of diabetic rats. islet transplant; insulin secretion; viability THE RISE IN CASES OF DIABETES MELLITUS in the United States has been called an epidemic. It is the third leading cause of death by disease and rivals heart disease and cancer as a major killer of United States citizens. For unexplained reasons the occurrence of type 1 diabetes is increasing worldwide, and the age of onset has decreased by 3-5 yr over the past decade so that many children now develop diabetes before entering school. The result is that more people with diabetes will spend a larger percentage of their life at risk for developing the chronic complications related to type 1 diabetes. Because the risk for development of most of the chronic complications associated with diabetes is related to glycemic control, significant attention is directed toward novel therapies, such as islet transplantation, to improve glycemic control.Islet transplants in humans were first attempted in the 1980s (7, 8). Initial success rates for human islet transplantation were disappointing, with only 5% of patients receiving transplants achieving partial function (19). Amid the failures were isolated success stories of individuals achieving prolonged reversal of their diabetes for a 1-to 2-yr period (19), which encouraged researchers to continue this approach for the treatment of diabetes. In 2000, islet transplantations were performed successfully on seven patients with diabetes by using a suppression regimen that omitted glucocorticoid...

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Summary Background Type 1 diabetes (T1D) results from autoimmune targeting of the pancreatic beta cells, likely mediated by effector memory T cells (Tems). CD2, a T cell surface protein highly expressed on Tems, is targeted by the fusion protein alefacept, depleting Tems and central memory T cells (Tcms). We hypothesized that alefacept would arrest autoimmunity and preserve residual beta cells in newly diagnosed T1D. Methods The T1DAL study is a phase II, double-blind, placebo-controlled trial that randomised T1D patients 12-35 years old within 100 days of diagnosis, 33 to alefacept (two 12-week courses of 15 mg IM per week, separated by a 12-week pause) and 16 to placebo, at 14 US sites. The primary endpoint was the change from baseline in mean 2-hour C-peptide area under the curve (AUC) at 12 months. This trial is registered with ClinicalTrials.gov, number NCT00965458. Findings The mean 2-hour C-peptide AUC at 12 months increased by 0.015 nmol/L (95% CI -0.080 to 0.110 nmol/L) in the alefacept group and decreased by 0.115 nmol/L (95% CI -0.278 to 0.047) in the placebo group, which was not significant (p=0.065). However, key secondary endpoints were met: the mean 4-hour C-peptide AUC was significantly higher (p=0.019), and daily insulin use and the rate of hypoglycemic events were significantly lower (p=0.02 and p<0.001, respectively) at 12 months in the alefacept vs. placebo groups. Safety and tolerability were comparable between groups. There was targeted depletion of Tems and Tcms, with sparing of naïve and regulatory T cells (Tregs). Interpretation At 12 months, alefacept preserved the 4-hour C-peptide AUC, lowered insulin use, and reduced hypoglycemic events, suggesting a signal of efficacy. Depletion of memory T cells with sparing of Tregs may be a useful strategy to preserve beta cell function in new-onset T1D.

Summary Background Type 1 diabetes results from T-cell-mediated destruction of β cells. Findings from preclinical studies and pilot clinical trials suggest that antithymocyte globulin (ATG) might be effective for reducing this autoimmune response. We assessed the safety and efficacy of rabbit ATG in preserving islet function in participants with recent-onset type 1 diabetes, and report here our 12-month results. Methods For this phase 2, randomised, placebo-controlled, clinical trial, we enrolled patients with recent-onset type 1 diabetes, aged 12–35 years, and with a peak C-peptide of 0·4 nM or greater on mixed meal tolerance test from 11 sites in the USA. We used a computer generated randomisation sequence to randomly assign patients (2:1, with permuted-blocks of size three or six and stratified by study site) to receive either 6·5 mg/kg ATG or placebo over a course of four days. All participants were masked and initially managed by an unmasked drug management team, which managed all aspects of the study until month 3. Thereafter, to maintain masking for diabetes management throughout the remainder of the study, participants received diabetes management from an independent, masked study physician and nurse educator. The primary endpoint was the baseline-adjusted change in 2-h area under the curve C-peptide response to mixed meal tolerance test from baseline to 12 months. Analyses were by intention to treat. This is a planned interim analysis of an on-going trial that will run for 24 months of follow-up. This study is registered with ClinicalTrials.gov, number NCT00515099. Findings Between Sept 10, 2007, and June 1, 2011, we screened 154 individuals, randomly allocating 38 to ATG and 20 to placebo. We recorded no between-group difference in the primary endpoint: participants in the ATG group had a mean change in C-peptide area under the curve of −0·195 pmol/mL (95% CI −0·292 to −0·098) and those in the placebo group had a mean change of −0·239 pmol/mL (−0·361 to −0·118) in the placebo group (p=0·591). All except one participant in the ATG group had both cytokine release syndrome and serum sickness, which was associated with a transient rise in interleukin-6 and acute-phase proteins. Acute T cell depletion occurred in the ATG group, with slow reconstitution over 12 months. However, effector memory T cells were not depleted, and the ratio of regulatory to effector memory T cells declined in the first 6 months and stabilised thereafter. ATG-treated patients had 159 grade 3–4 adverse events, many associated with T-cell depletion, compared with 13 in the placebo group, but we detected no between-group difference in incidence of infectious diseases. Interpretation Our findings suggest that a brief course of ATG does not result in preservation of β-cell function 12 months later in patients with new-onset type 1 diabetes. Generalised T-cell depletion in the absence of specific depletion of effector memory T cells and preservation of regulatory T cells seems to be an ineffective treatment for type 1 diabetes.

Epithelioid and rhabdoid glioblastomas are rare entities that share some overlapping morphologic features, but remain poorly characterized at the immunohistochemical and genetic level. We report 10 examples: 8 epithelioid glioblastomas (E-GBMs) and 2 rhabdoid GBMs (R-GBMs). E-GBMs tended to be superficially located, circumscribed, supratentorial tumors composed of monotonous, discohesive sheets of small rounded cells that mimicked metastatic malignant melanoma. R-GBMs showed tumor with classic rhabdoid features arising as a subpopulation of an otherwise classic GBM, fitting the definition of composite extrarenal rhabdoid tumors. Polyphenotypic immunohistochemical expression and focal loss of INI-1 protein in the rhabdoid areas of R-GBMs distinguished them from E-GBMs. Monosomy 22 was identified in R-GBMs, but not E-GBMs. Immunostaining for claudin-6, a key component of tight junctions that we have earlier shown to be a positive cytoplasmic immunohistochemical marker for atypical teratoid or rhabdoid tumors (AT/RTs), was also conducted. None of the E-GBMs or R-GBMs showed claudin-6 cytoplasmic expression, including the focal areas in the 2 R-GBMs in which there was loss of INI-1 protein nuclear expression. Thus, in the CNS, claudin-6 expression may be a good discriminator of atypical teratoid or rhabdoid tumors from other CNS rhabdoid or epithelioid neoplasms.

By measuring [ 125 I]hGH binding in the plasma of human GH (hGH)-deficient children at 3-to 4-month intervals during hGH therapy with hGH prepared by Raben's method, we have defined three patterns of antibody formation. One group of patients developed antibodies by 3 months of therapy that persisted despite the length or type of hGH therapy. Their antibodies were characterized by a low affinity (1.49 x 10 9 M" 1 ) and a high capacity (29 nmol/liter plasma). The development or presence of antibodies adversely affected the growth rate in only one patient in this group. This patient's antibodies were characterized by the highest capacity (1235 nmol/liter plasma) and lowest affinity (0.044 x 10 9 M~"). The capacity decreased to 134 nmol/liter plasma upon switching to a hGH preparation without aggregated hGH.The second group developed antibodies to hGH by 6-9 months of therapy, but [ 125 I]hGH binding by the plasma returned to control levels by 20 months of therapy. The antibodies of this group were characterized by a higher affinity (12.7 x 10 9 M" 1 ) and a lower capacity (0.9 nmol/liter plasma) than the group with antibodies. This group had received hGH with less than 5% aggregated hGH.The third group did not develop significant ['"' r 'I]hGH binding in the plasma despite prolonged therapy with multiple hGH preparations.Several patients have been treated solely with recent hGH preparations from the National Pituitary Agency which contain less than 10% aggregated hGH compared to earlier preparations containing more than 20%. The incidence (44%) of significant [ 125 I]hGH binding by these patients' plasmas was similar to that of patients receiving hGH with aggregated hGH; however, hGH binding by the plasma of most of these patients was characteristic of that of patients with transient antibodies.We conclude that 1) the development of antibodies to hGH during therapy is dependent on individual susceptibility and the presence of aggregated hGH in the hGH preparation, 2) the antibody response is more likely to be transient if the content of aggregated hGH is low, and 3) the eventual incidence of significant hGH binding in plasma of patients who receive hGH prepared by Raben's method without aggregated hGH will be the same as that observed in patients receiving hGH prepared by other methods. (J Clin Endocrinol Metab 51: 691, 1980)