Biomarkers of vascular disease in diabetes: the adipose-immune system cross talk

Experimental and clinical studies aimed at investigating the mechanism(s) underlying vascular complications of diabetes indicate that a great number of molecules are involved in the pathogenesis of these complications. Most of these molecules are inflammatory mediators or markers generated by immune or adipose tissue. Some of them, i.e. resistin and sortilin, have been shown to be involved in the cross talk between adipocytes and inflammatory cells. This interaction is an attractive area of research, particularly in type 2 diabetes and obesity. Other proteins, such as adiponectin and visfatin, appear to be more promising as possible vascular markers. In addition, some molecules involved in calcium/phosphorus metabolism, such as klotho and FGF23, have an involvement in the pathogenesis of diabetic vasculopathy, which appears to be dependent on the degree of vascular impairment. Inflammatory markers are a promising tool for treatment decisions while measuring plasma levels of adipokines, sortilin, Klotho and FGF23 in adequately sized longitudinal studies is expected to allow a more precise characterization of diabetic vascular disease and the optimal use of personalized treatment strategies.

Frequent and specific immunity to the embryonal stem cell-associated antigen SOX2 in patients with monoclonal gammopathy

Specific targets of cellular immunity in human premalignancy are largely unknown. Monoclonal gammopathy of undetermined significance (MGUS) represents a precursor lesion to myeloma (MM). We show that antigenic targets of spontaneous immunity in MGUS differ from MM. MGUS patients frequently mount a humoral and cellular immune response against SOX2, a gene critical for self-renewal in embryonal stem cells. Intranuclear expression of SOX2 marks the clonogenic CD138⁻ compartment in MGUS. SOX2 expression is also detected in a proportion of CD138⁺ cells in MM patients. However, these patients lack anti-SOX2 immunity. Cellular immunity to SOX2 inhibits the clonogenic growth of MGUS cells in vitro. Detection of anti-SOX2 T cells predicts favorable clinical outcome in patients with asymptomatic plasmaproliferative disorders. Harnessing immunity to antigens expressed by tumor progenitor cells may be critical for prevention and therapy of human cancer.

Identification of SOX2 as a novel glioma-associated antigen and potential target for T cell-based immunotherapy

Prognosis for patients suffering from malignant glioma has not substantially improved. Specific immunotherapy as a novel treatment concept critically depends on target antigens, which are highly overexpressed in the majority of gliomas, but the number of such antigens is still very limited. SOX2 was identified by screening an expression database for transcripts that are overexpressed in malignant glioma, but display minimal expression in normal tissues. Expression of SOX2 mRNA was further investigated in tumour and normal tissues by real-time PCR. Compared to cDNA from pooled normal brain, SOX2 was overexpressed in almost all (9 out of 10) malignant glioma samples, whereas expression in other, non-malignant tissues was almost negligible. SOX2 protein expression in glioma cell lines and tumour tissues was verified by Western blot and immunofluorescence. Immunohistochemistry demonstrated SOX2 protein expression in all malignant glioma tissues investigated ranging from 6 to 66% stained tumour cells. Human leucocyte antigen-A^*0201-restricted SOX2-derived peptides were tested for the activation of glioma-reactive CD8+ cytotoxic T lymphocytes (CTLs). Specific CTLs were raised against the peptide TLMKKDKYTL and were capable of lysing glioma cells. The abundant and glioma-restricted overexpression of SOX2 and the generation of SOX2-specific and tumour-reactive CTLs may recommend this antigen as target for T-cell-based immunotherapy of glioma.

Frequency of SOX Group B (SOX1, 2, 3) and ZIC2 antibodies in Turkish patients with small cell lung carcinoma and their correlation with clinical parameters

BACKGROUND

Expression of neuroectodermal markers is a key feature of small cell lung carcinoma (SCLC). Although immune responses against a number of these proteins have been associated with paraneoplastic neuronal disease (PND), most patients with SCLC have anti-neuroectodermal antibodies in the absence of PND. Whether these immune responses affect the clinical outcome in SCLC is critical in understanding the potential value of these proteins as cancer vaccine targets as well as in the pathogenesis of PND.

METHODS

The authors investigated the frequency of immunoglobulin G autoantibodies against Sry-like high-mobility group box (SOX)1, 2, 3 and Zinc-finger gene of the cerebellum (ZIC)2 proteins in stored serum samples from 90 patients utilizing the lambda-phage plaque assay. Data obtained from patient records were utilized to measure clinical correlates of seroreactivity.

RESULTS

Antibodies to SOX1 were present in 28% of patients and another 28% had anti-ZIC2 antibodies, classifying these as some of the most frequent antibody responses observed in SCLC. None had autoimmune paraneoplastic disease. Antibody titers were frequently as high as > or = 1:10(6) and were stable for < or = 6 months after diagnosis. Seroreactivity against either SOX1 or ZIC2 correlated with younger age, lower lactate dehydrogenase levels, and better response to initial therapy.

CONCLUSIONS

The frequent and stable presence of SOX Group B and/or ZIC2 antibodies in SCLC, but not in healthy individuals examined, indicates they are serological markers of SCLC. However, the correlation between known clinical parameters of less aggressive disease and seroreactivity suggests that these antibodies are indicators of better prognosis in SCLC and warrants further studies to clarify the nature of the underlying immune responses.