Ibrutinib-based therapy reinvigorates CD8+ T cells compared to chemoimmunotherapy: immune monitoring from the E1912 trial

ABSTRACT

Bruton tyrosine kinase inhibitors (BTKis) that target B-cell receptor signaling have led to a paradigm shift in chronic lymphocytic leukemia (CLL) treatment. BTKis have been shown to reduce abnormally high CLL-associated T-cell counts and the expression of immune checkpoint receptors concomitantly with tumor reduction. However, the impact of BTKi therapy on T-cell function has not been fully characterized. Here, we performed longitudinal immunophenotypic and functional analysis of pretreatment and on-treatment (6 and 12 months) peripheral blood samples from patients in the phase 3 E1912 trial comparing ibrutinib-rituximab with fludarabine, cyclophosphamide, and rituximab (FCR). Intriguingly, we report that despite reduced overall T-cell counts; higher numbers of T cells, including effector CD8+ subsets at baseline and at the 6-month time point, associated with no infections; and favorable progression-free survival in the ibrutinib-rituximab arm. Assays demonstrated enhanced anti-CLL T-cell killing function during ibrutinib-rituximab treatment, including a switch from predominantly CD4+ T-cell:CLL immune synapses at baseline to increased CD8+ lytic synapses on-therapy. Conversely, in the FCR arm, higher T-cell numbers correlated with adverse clinical responses and showed no functional improvement. We further demonstrate the potential of exploiting rejuvenated T-cell cytotoxicity during ibrutinib-rituximab treatment, using the bispecific antibody glofitamab, supporting combination immunotherapy approaches.

Tumor-activated lymph node fibroblasts suppress T cell function in diffuse large B cell lymphoma

Recent transcriptomic-based analysis of diffuse large B cell lymphoma (DLBCL) has highlighted the clinical relevance of LN fibroblast and tumor-infiltrating lymphocyte (TIL) signatures within the tumor microenvironment (TME). However, the immunomodulatory role of fibroblasts in lymphoma remains unclear. Here, by studying human and mouse DLBCL-LNs, we identified the presence of an aberrantly remodeled fibroblastic reticular cell (FRC) network expressing elevated fibroblast-activated protein (FAP). RNA-Seq analyses revealed that exposure to DLBCL reprogrammed key immunoregulatory pathways in FRCs, including a switch from homeostatic to inflammatory chemokine expression and elevated antigen-presentation molecules. Functional assays showed that DLBCL-activated FRCs (DLBCL-FRCs) hindered optimal TIL and chimeric antigen receptor (CAR) T cell migration. Moreover, DLBCL-FRCs inhibited CD8+ TIL cytotoxicity in an antigen-specific manner. Notably, the interrogation of patient LNs with imaging mass cytometry identified distinct environments differing in their CD8+ TIL-FRC composition and spatial organization that associated with survival outcomes. We further demonstrated the potential to target inhibitory FRCs to rejuvenate interacting TILs. Cotreating organotypic cultures with FAP-targeted immunostimulatory drugs and a bispecific antibody (glofitamab) augmented antilymphoma TIL cytotoxicity. Our study reveals an immunosuppressive role of FRCs in DLBCL, with implications for immune evasion, disease pathogenesis, and optimizing immunotherapy for patients.

Loss of TET2 in human hematopoietic stem cells alters the development and function of neutrophils

Somatic mutations commonly occur in hematopoietic stem cells (HSCs). Some mutant clones outgrow through clonal hematopoiesis (CH) and produce mutated immune progenies shaping host immunity. Individuals with CH are asymptomatic but have an increased risk of developing leukemia, cardiovascular and pulmonary inflammatory diseases, and severe infections. Using genetic engineering of human HSCs (hHSCs) and transplantation in immunodeficient mice, we describe how a commonly mutated gene in CH, TET2, affects human neutrophil development and function. TET2 loss in hHSCs produce a distinct neutrophil heterogeneity in bone marrow and peripheral tissues by increasing the repopulating capacity of neutrophil progenitors and giving rise to low-granule neutrophils. Human neutrophils that inherited TET2 mutations mount exacerbated inflammatory responses and have more condensed chromatin, which correlates with compact neutrophil extracellular trap (NET) production. We expose here physiological abnormalities that may inform future strategies to detect TET2-CH and prevent NET-mediated pathologies associated with CH.

The immunomodulatory molecule TIGIT is expressed by chronic lymphocytic leukemia cells and contributes to anergy

T-cell immunoreceptor with Ig and ITIM domains (TIGIT) is an inhibitory checkpoint receptor that negatively regulates T cell responses. CD226 competes with TIGIT for binding to the CD155 ligand, delivering a positive signal to the T cell. Here we studied expression of TIGIT and CD226 in a cohort of 115 chronic lymphocytic leukemia (CLL) patients and report expression of TIGIT and CD226 by leukemic cells. By devising a TIGIT/CD226 ratio, we showed that CLL cells favoring TIGIT over CD226 are typical of a more indolent disease, while those favoring CD226 are characterized by a shorter time-to-first-treatment and shorter progression-fee survival after first treatment. TIGIT expression was inversely correlated to the B cell receptor (BCR) signaling capacity, as determined by studying BTK phosphorylation, cell proliferation and IL-10 production. In CLL cells treated with ibrutinib, where surface IgM and BCR signaling capacity are temporarily increased, TIGIT expression was downmodulated, in line with data indicating transient recovery from anergy. Lastly, cells from Richter syndrome patients were characterized by high levels of CD226, with low to undetectable TIGIT, in keeping with their high proliferative drive. Together, these data suggest that TIGIT contributes to CLL anergy by downregulating BCR signaling, identifying novel and actionable molecular circuits regulating anergy and modulating CLL cell functions.

Efficacy and Safety of Ensovibep for Adults Hospitalized With COVID-19 : A Randomized Controlled Trial

BACKGROUND

Ensovibep (MP0420) is a designed ankyrin repeat protein, a novel class of engineered proteins, under investigation as a treatment of SARS-CoV-2 infection.

OBJECTIVE

To investigate if ensovibep, in addition to remdesivir and other standard care, improves clinical outcomes among patients hospitalized with COVID-19 compared with standard care alone.

DESIGN

Double-blind, randomized, placebo-controlled, clinical trial. (ClinicalTrials.gov: NCT04501978).

SETTING

Multinational, multicenter trial.

PARTICIPANTS

Adults hospitalized with COVID-19.

INTERVENTION

Intravenous ensovibep, 600 mg, or placebo.

MEASUREMENTS

Ensovibep was assessed for early futility on the basis of pulmonary ordinal scores at day 5. The primary outcome was time to sustained recovery through day 90, defined as 14 consecutive days at home or place of usual residence after hospital discharge. A composite safety outcome that included death, serious adverse events, end-organ disease, and serious infections was assessed through day 90.

RESULTS

An independent data and safety monitoring board recommended that enrollment be halted for early futility after 485 patients were randomly assigned and received an infusion of ensovibep (n = 247) or placebo (n = 238). The odds ratio (OR) for a more favorable pulmonary outcome in the ensovibep (vs. placebo) group at day 5 was 0.93 (95% CI, 0.67 to 1.30; P = 0.68; OR > 1 would favor ensovibep). The 90-day cumulative incidence of sustained recovery was 82% for ensovibep and 80% for placebo (subhazard ratio [sHR], 1.06 [CI, 0.88 to 1.28]; sHR > 1 would favor ensovibep). The primary composite safety outcome at day 90 occurred in 78 ensovibep participants (32%) and 70 placebo participants (29%) (HR, 1.07 [CI, 0.77 to 1.47]; HR < 1 would favor ensovibep).

LIMITATION

The trial was prematurely stopped because of futility, limiting power for the primary outcome.

CONCLUSION

Compared with placebo, ensovibep did not improve clinical outcomes for hospitalized participants with COVID-19 receiving standard care, including remdesivir; no safety concerns were identified.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Understanding the Immune-Stroma Microenvironment in B Cell Malignancies for Effective Immunotherapy

Cancers, including lymphomas, develop in complex tissue environments where malignant cells actively promote the creation of a pro-tumoral niche that suppresses effective anti-tumor effector T cell responses. Research is revealing that the tumor microenvironment (TME) differs between different types of lymphoma, covering inflamed environments, as exemplified by Hodgkin lymphoma, to non-inflamed TMEs as seen in chronic lymphocytic leukemia (CLL) or diffuse-large B-cell lymphoma (DLBCL). In this review we consider how T cells and interferon-driven inflammatory signaling contribute to the regulation of anti-tumor immune responses, as well as sensitivity to anti-PD-1 immune checkpoint blockade immunotherapy. We discuss tumor intrinsic and extrinsic mechanisms critical to anti-tumor immune responses, as well as sensitivity to immunotherapies, before adding an additional layer of complexity within the TME: the immunoregulatory role of non-hematopoietic stromal cells that co-evolve with tumors. Studying the intricate interactions between the immune-stroma lymphoma TME should help to design next-generation immunotherapies and combination treatment strategies to overcome complex TME-driven immune suppression.

Lymphoid interstitial pneumonitis in a newly diagnosed late presenter of human immunodeficiency virus infection: a case report

Background

An increase has been described throughout the years in the frequency of various uncommon diseases in people living with human immunodeficiency virus (HIV). Particularly late presenters are associated with a significant risk not only for acquired immune deficiency syndrome (AIDS)-defining conditions but also for non AIDS-defining diseases which aggravate the prognosis of patients. Lymphoid interstitial pneumonitis (LIP) is one of these conditions described more often after the onset of HIV epidemic. LIP is a benign polyclonal lymphoproliferative disorder of the lung with not well characterized clinical and radiographic findings.

Case presentation

We report the diagnostic approach and clinical progress of a newly diagnosed late presenter of HIV infection with respiratory problems in our HIV unit. The findings of computed tomography indicated the diagnosis of HIV-associated LIP, although this condition is mainly described in a normal range of CD4 cell count.

Conclusion

This case presentation highlights the importance of timely diagnosis and initiation of antiretroviral therapy. The increase of CD4 cell count and viral suppression may improve the symptoms of LIP.

Triggering interferon signaling in T cells with avadomide sensitizes CLL to anti-PD-L1/PD-1 immunotherapy

Cancer treatment has been transformed by checkpoint blockade therapies, with the highest anti-tumor activity of anti-programmed death 1 (PD-1) antibody therapy seen in Hodgkin lymphoma. Disappointingly, response rates have been low in the non-Hodgkin lymphomas, with no activity seen in relapsed/refractory chronic lymphocytic leukemia (CLL) with PD-1 blockade. Thus, identifying more powerful combination therapy is required for these patients. Here, we preclinically demonstrate enhanced anti-CLL activity following combinational therapy with anti-PD-1 or anti-PD-1 ligand (PD-L1) and avadomide, a cereblon E3 ligase modulator (CELMoD). Avadomide induced type I and II interferon (IFN) signaling in patient T cells, triggering a feedforward cascade of reinvigorated T-cell responses. Immune modeling assays demonstrated that avadomide stimulated T-cell activation, chemokine expression, motility and lytic synapses with CLL cells, as well as IFN-inducible feedback inhibition through upregulation of PD-L1. Patient-derived xenograft tumors treated with avadomide were converted to CD8+ T cell-inflamed tumor microenvironments that responded to anti-PD-L1/PD-1-based combination therapy. Notably, clinical analyses showed increased PD-L1 expression on T cells, as well as intratumoral expression of chemokine signaling genes in B-cell malignancy patients receiving avadomide-based therapy. These data illustrate the importance of overcoming a low inflammatory T-cell state to successfully sensitize CLL to checkpoint blockade-based combination therapy.

T-Cell Dynamics in Chronic Lymphocytic Leukemia under Different Treatment Modalities

PURPOSE

Using next-generation sequencing (NGS), we recently documented T-cell oligoclonality in treatment-naïve chronic lymphocytic leukemia (CLL), with evidence indicating T-cell selection by restricted antigens.

EXPERIMENTAL DESIGN

Here, we sought to comprehensively assess T-cell repertoire changes during treatment in relation to (i) treatment type [fludarabine-cyclophosphamide-rituximab (FCR) versus ibrutinib (IB) versus rituximab-idelalisib (R-ID)], and (ii) clinical response, by combining NGS immunoprofiling, flow cytometry, and functional bioassays.

RESULTS

T-cell clonality significantly increased at (i) 3 months in the FCR and R-ID treatment groups, and (ii) over deepening clinical response in the R-ID group, with a similar trend detected in the IB group. Notably, in constrast to FCR that induced T-cell repertoire reconstitution, B-cell receptor signaling inhibitors (BcRi) preserved pretreatment clones. Extensive comparisons both within CLL as well as against T-cell receptor sequence databases showed little similarity with other entities, but instead revealed major clonotypes shared exclusively by patients with CLL, alluding to selection by conserved CLL-associated antigens. We then evaluated the functional effect of treatments on T cells and found that (i) R-ID upregulated the expression of activation markers in effector memory T cells, and (ii) both BcRi improved antitumor T-cell immune synapse formation, in marked contrast to FCR.

CONCLUSIONS

Taken together, our NGS immunoprofiling data suggest that BcRi retain T-cell clones that may have developed against CLL-associated antigens. Phenotypic and immune synapse bioassays support a concurrent restoration of functionality, mostly evident for R-ID, arguably contributing to clinical response.

Correlation of cardiac autonomic neuropathy with small and large peripheral nerve function in type 2 diabetes mellitus

AIMS

To analyse the correlation of cardiac autonomic neuropathy (CAN), sympathetic and parasympathetic dysfunction with the different diagnostic tools for large and small peripheral nerve fibres in type 2 diabetes mellitus (T2DM).

METHODS

We included 153 T2DM subjects (92 men) with mean age of 64.4 years. CAN, as well as sympathetic and parasympathetic dysfunction were diagnosed by the Ewing's cardiovascular reflex tests. Vibration perception threshold (VPT), monofilament, Ipswich Touch test, automated sural nerve conduction study and neuropathy disability score (NDS) evaluated large and small peripheral nerve fibre function.

RESULTS

CAN (adjusted odds ratio [aOR]: 44.57), parasympathetic (aOR: 18.40) and sympathetic dysfunction (aOR: 5.50) correlated with measures of small fibre function evaluated by pinprick sensation and temperature perception. Among tools for large nerve fibres, positive correlation was shown between: (1) CAN and abnormal VPT (aOR: 16.78), (2) parasympathetic dysfunction and abnormal VPT (aOR: 39.47).

CONCLUSIONS

CAN and parasympathetic dysfunction correlate with peripheral neuropathy, especially when the latter is assessed through VPT and measures of small fibre function as evaluated by pinprick sensation and temperature perception. The latter additionally correlate with sympathetic nervous system impairment.

Combination lenalidomide-rituximab immunotherapy activates anti-tumour immunity and induces tumour cell death by complementary mechanisms of action in follicular lymphoma

Chemotherapy plus rituximab has been the mainstay of treatment for follicular lymphoma (FL) for two decades but is associated with immunosuppression and relapse. In phase 2 studies, lenalidomide combined with rituximab (R²) has shown clinical synergy in front‐line and relapsed/refractory FL. Here, we show that lenalidomide reactivated dysfunctional T and Natural Killer (NK) cells ex vivo from FL patients by enhancing proliferative capacity and T‐helper cell type 1 (Th1) cytokine release. In combination with rituximab, lenalidomide improved antibody‐dependent cellular cytotoxicity in sensitive and chemo‐resistant FL cells, via a cereblon‐dependent mechanism. While single‐agent lenalidomide and rituximab increased formation of lytic NK cell immunological synapses with primary FL tumour cells, the combination was superior and correlated with enhanced cytotoxicity. Immunophenotyping of FL patient samples from a phase 3 trial revealed that R² treatment increased circulating T‐ and NK‐cell counts, while R‐chemotherapy was associated with reduced cell numbers. Finally, using an in vitro model of myeloid differentiation, we demonstrated that lenalidomide caused a reversible arrest in neutrophil maturation that was distinct from a cytotoxic chemotherapeutic agent, which may help explain the lower rates of neutropenia observed with R²versus R‐chemotherapy. Taken together, we believe these data support a paradigm shift in the treatment of FL – moving from combination immunochemotherapy to chemotherapy‐free immunotherapy.

Integrated epigenomic and transcriptomic analysis reveals TP63 as a novel player in clinically aggressive chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) stereotyped subsets #6 and #8 include cases expressing unmutated B cell receptor immunoglobulin (BcR IG) (U-CLL). Subset #6 (IGHV1-69/IGKV3-20) is less aggressive compared to subset #8 (IGHV4-39/IGKV1(D)-39) which has the highest risk for Richter's transformation among all CLL. The underlying reasons for this divergent clinical behavior are not fully elucidated. To gain insight into this issue, here we focused on epigenomic signatures and their links with gene expression, particularly investigating genome-wide DNA methylation profiles in subsets #6 and #8 as well as other U-CLL cases not expressing stereotyped BcR IG. We found that subset #8 showed a distinctive DNA methylation profile compared to all other U-CLL cases, including subset #6. Integrated analysis of DNA methylation and gene expression revealed significant correlation for several genes, particularly highlighting a relevant role for the TP63 gene which was hypomethylated and overexpressed in subset #8. This observation was validated by quantitative PCR, which also revealed TP63 mRNA overexpression in additional nonsubset U-CLL cases. BcR stimulation had distinct effects on p63 protein expression, particularly leading to induction in subset #8, accompanied by increased CLL cell survival. This pro-survival effect was also supported by siRNA-mediated downregulation of p63 expression resulting in increased apoptosis. In conclusion, we report that DNA methylation profiles may vary even among CLL patients with similar somatic hypermutation status, supporting a compartmentalized approach to dissecting CLL biology. Furthermore, we highlight p63 as a novel prosurvival factor in CLL, thus identifying another piece of the complex puzzle of clinical aggressiveness.

Retinol Binding Protein-4 and Adiponectin Levels in Thyroid Overt and Subclinical Dysfunction

Thyroid dysfunction is accompanied by numerous changes in intermediary metabolism. Retinol binding protein-4 (RBP-4) and adiponectin are 2 adipocytokines that have multiple metabolic functions. The aim of our study was to examine serum RBP4 and adiponectin levels in clinical (before and after therapy) and subclinical hyperthyroid and hypothyroid subjects as compared to controls.150 patients with thyroid dysfunction were recruited (65 hyperthyroid and 85 hypothyroid) while 28 euthyroid subjects served as a control group. We measured anthropometric, biochemical and hormonal (free T4, free T3, TSH, insulin) parameters in all participants. RBP-4 and adiponectin were measured using commercial ELISA kits.Mean baseline levels of RBP-4 were higher in patients with clinical hypothyroidism (29.0±10.2 ng/ml, 25.1±12.6 ng/ml, 38.8±16.5 ng/ml, 31.9±13.2 ng/ml, 20.4±8.2 ng/ml in patients with hyperthyroidism, subclinical hyperthryrodism, hypothyroidism, subclinical hypothyroidism and controls respectively, F=4.86, P<0.001) and decreased significantly in patients with clinical hyperthyroidism and hypothyroidism after normalization of thyroid hormones' levels (from 29.0±10.2 to 24.9±8.4 ng/ml, p=0.003 and from 38.8±16.5 to 29.0±10.8 ng/ml, p=0.001 respectively). We did not observe analogous changes in adiponectin levels in any of the studied groups.RBP-4 levels are higher in patients with clinical hypothyroidism and exhibit a marked decrease after normalization of thyroid function in both hyper and hypothyroid patients. We suggest that RBP-4 may play a role in the metabolic disturbances which accompany thyroid dysfunction.

Monocyte chemoattractant protein 1 is correlated with glycemic control and peripheral arterial disease in type 2 diabetic patients with metabolic syndrome

We evaluated the serum levels of monocyte chemoattractant protein 1 (MCP-1) and their association with peripheral arterial disease (PAD) in 199 patients with type 2 diabetes mellitus (T2DM) and metabolic syndrome ([MetS], group A) in comparison with 109 healthy controls (group B). In group A, MCP-1 levels were significantly (P < .001) higher than group B and exhibited a positive correlation with HbA1c (P < .001) and a negative correlation with ankle-brachial index (P < .001). In the same group, patients with PAD had significantly higher MCP-1 levels compared with those without PAD (P < .001). In conclusion, T2DM patients with MetS exhibit higher serum MCP-1 levels. The latter is associated with worse glycemic control and PAD. These results suggest a potential contributory role for MCP-1 in the pathogenesis of PAD in the presence of hyperglycemia and MetS in T2DM.

Peripheral neuropathy is associated with increased serum levels of uric acid in type 2 diabetes mellitus

We assessed serum uric acid (SUA) levels in patients with type 2 diabetes mellitus (T2DM) with or without peripheral neuropathy (diagnosed by the Neuropathy Disability score [NDS]). We enrolled 64 patients with T2DM with peripheral neuropathy (group A: 31 men, mean age 63.0 ± 2.8 years) and 66 age-, gender-, renal function- and T2DM duration-matched patients without neuropathy (group B: 32 men, mean age 62.4 ± 3.1 years). Serum uric acid was significantly higher in group A (P < .001). There was a significant correlation between SUA and NDS in both groups (group A: r(s) = .93, P < .001; group B: r( s) = .95, P < .001). C-reactive protein (CRP) was also significantly higher in group A (P < .001) and correlated significantly with SUA in both groups (group A: r(s) = .93, P < .001; group B: r(s) = .87, P < .001). Serum uric acid is increased in patients with T2DM with neuropathy versus those without. Whether SUA is involved in the pathogenesis of T2DM peripheral neuropathy remains to be established.

Lanarkshire Oximetry Index as a Diagnostic Tool for Peripheral Arterial Disease in Type 2 Diabetes: A Pilot Study

We evaluated the Lanarkshire Oximetry Index (LOI) for the diagnosis of peripheral arterial disease (PAD) in type 2 diabetic patients, using the Ankle-Brachial Index (ABI) as gold standard. We included 161 patients (71 men, mean age 63.1 ± 9.8 years). Peripheral arterial disease was defined as ABI < 0.9. Two cut-off values of LOI (<0.9 and <0.8) were assessed for the diagnosis of PAD. Sensitivity and specificity for PAD were 93.3% and 89.1%, respectively, using a LOI cut-off value of 0.9, while they were 40% and 99.3%, respectively, using a LOI cut-off value of 0.8. Agreement between LOI and ABI was moderate (P < .001). There was a significant positive correlation between ABI and LOI (r = .377, P < .001). Lanarkshire Oximetry Index is a potentially useful alternative diagnostic test for PAD in type 2 diabetes. A cut-off value of 0.9 has high sensitivity and modest specificity. Agreement between LOI and ABI is moderate.

Glycaemic control is correlated with well-being index (WHO-5) in subjects with type 2 diabetes

The aim of this study was to examine the potential correlation of WHO-5 well-being index with glycaemic control and chronic complications in subjects with type 2 diabetes. The study included 156 subjects (73 men, mean age 64.05+/-9.11 years, mean diabetes duration 12.22+/-5.61 years). Well-being was assessed by the WHO-5 score via a validated questionnaire comprising 5 questions (Q1-Q5). HbA (1c) showed a significant negative correlation with overall WHO-5 score (r (s)=-0.248, p=0.002) and individual Q1-Q4 scores (r (s)=-0.262, p=0.001; r (s)=-0.248, p=0.002; r (s)=-0.207, p=0.009 and r (s)=-0.169, p=0.035 respectively). Subjects with adequate glycaemic control (HbA (1c) < 7%, n=67) had a significantly higher WHO-5 score in comparison to those with inadequate glycaemic control (HbA (1c) >or= 7%, n=89) (mean+/-SD: 19.69+/-5.47 vs. mean+/-SD: 17.11+/-6.38, p=0.011). Finally, WHO-5 score was significantly (p=0.013) lower in subjects with neuropathic pain than in those without neuropathic pain.

CONCLUSIONS

In type 2 diabetic subjects, glycaemic control shows a significant correlation with well-being, while neuropathic pain is associated with lower well-being score.

The fatty acid amide hydrolase (FAAH) Pro129Thr polymorphism is not associated with severe obesity in Greek subjects

Fatty amid acid hydrolase (FAAH) has been implicated at both protein and gene level with obesity. An association between Pro129Thr variant of the FAAH gene and obesity has been described, but various studies have yielded conflicting results. Our aim was to determine whether this polymorphism is related to severe obesity and whether it confers a risk for variability of quantitative metabolic traits in a cohort of Greek obese subjects. Two groups of severely obese subjects (BMI > 40 kg/m (2)) were studied: a group of 158 metabolically healthy and a group of 145 obese subjects with metabolic syndrome, which were compared to a control group consisting of 121 lean individuals. We did not find any association between the Pro129Thr polymorphism with severe obesity in both subgroups of obese subjects, between these two subgroups (p= 0.11) or on basic anthropometric characteristics in the three groups. Statistically significant differences were found for glucose and HDL in metabolically healthy subjects and HDL in the control group. The borderline significant p-values were not significant after correction for multiple testing. We were unable to find robust evidence of an association of the Pro129Thr variant with severe obesity, and any related quantitative traits among the obese Greek subjects examined.

A comparison of the new indicator test for sudomotor function (Neuropad) with the vibration perception threshold and the clinical examination in the diagnosis of peripheral neuropathy in subjects with type 2 diabetes

Peripheral neuropathy remains a major cause of morbidity and is a cardinal factor in the pathogenesis of diabetic foot ulceration. The aim of the present study was to compare the new indicator test for sudomotor function (Neuropad) with the vibration perception threshold (VPT) and the clinical examination in the diagnosis of peripheral neuropathy in subjects with type 2 diabetes. This study included 154 type 2 diabetic patients (76 men) with a mean age of 64.3+/-7.3 years and a mean diabetes duration of 12.8+/-4.3 years. Neuropathy was diagnosed clinically using the Neuropathy Disability Score (NDS). The VPT was measured with a neurothesiometer, values > 25Volts being classified as abnormal. Sudomotor function was evaluated by the indicator test. Sensitivity of the indicator test for neuropathy was 97.8% and specificity was 67.2%. Sensitivity and specificity of VPT for neuropathy were 78.9% and 85.9% respectively. A significant correlation was shown between time to colour change of the indicator test and VPT (rs=0.889, p<0.001).

CONCLUSIONS

Both the indicator test and the VPT have a high sensitivity for neuropathy. Sensitivity is higher with the indicator test, but specificity is higher with VPT. Time until complete colour change of the indicator test shows a positive correlation with VPT. Thus, the indicator test appears to be a useful additional diagnostic tool of neuropathy, particularly suitable for screening and self-examination, in type 2 diabetes. The correlation between time to colour change of the indicator test and VPT is interesting and merits investigation in a prospective study.

An insertion/deletion polymorphism in the alpha2B adrenoceptor gene is associated with peripheral neuropathy in patients with type 2 diabetes mellitus

Alpha2B adrenoceptor (alpha2B-AR) mediates a variety of functions in humans. An insertion/deletion (I/D) polymorphism of the alpha2B-AR gene located on chromosome 2 has been described. The aim of the present study was to investigate the potential association between alpha2B gene I/D polymorphism and peripheral neuropathy in Greek patients with type 2 diabetes mellitus. The study included 130 patients (70 men) with diabetic neuropathy (group A) and 60 patients (34 men) without diabetic neuropathy (group B). There was no difference in age, gender and diabetes duration between the groups. Diabetic neuropathy was diagnosed by clinical examination using the Diabetic Neuropathy Index (DNI). Genotyping of I/D polymorphism was performed by PCR. Frequency of the D allele was significantly higher (p=0.001) in group A (26.9%) as compared to group B (11.7%). DNI score differed significantly (p=0.001) between the three genotype groups (I/I, I/D, D/D). It was significantly higher (p=0.04) in patients with I/D (3.7+/-1) than in those with I/I (2.5+/-0.9) and significantly higher (p=0.001) in patients with D/D (5.6+/-1.3) than in those with I/D (3.7+/-1).

CONCLUSIONS

Patients with neuropathy exhibit a significantly higher frequency of the D allele in comparison to those without neuropathy. Presence of the D allele is also associated with a higher neuropathic score. These results provide evidence for an association of the D allele with both presence and severity of neuropathy in patients with type 2 diabetes mellitus.

Use of the new indicator test (Neuropad) for the assessment of the staged severity of neuropathy in type 2 diabetic patients

The new indicator test for sudomotor function (Neuropad) has been shown to represent a highly sensitive and reproducible tool for the diagnosis of diabetic peripheral neuropathy. This study aimed to examine the utility of the indicator test in the assessment of the staged severity of neuropathy in patients with type 2 diabetes mellitus. The study included 120 type 2 diabetic patients (58 men) with a mean age of 67.3+/-5.9 years and a mean diabetes duration of 13.1+/-3.2 years. Neuropathy was diagnosed and staged by clinical examination and nerve conduction study, according to the Michigan classification system. Patients were also examined with the indicator test, applied on the plantar aspect of the feet. Time until complete colour change of the test was recorded and stratified into deciles according to the spread of measurements in the study population. Neuropathy was staged as class 0 in 37 patients, class 1 in 44 patients, class 2 in 28 patients and class 3 in 11 patients. Time until complete colour change was 436.5+/-62.9, 740+/-88.1, 1192.5+/-161 and 1817.3+/-127.4 seconds in patients staged as class 0, 1, 2 and 3 respectively (p=0.001). Use of a threshold lower than 530 seconds until complete colour change had 97% sensitivity and 100% specificity for diagnosis of class 0 neuropathy. Use of a threshold lower than 1000 seconds until complete colour change had 100% sensitivity and 97% specificity for class 1 neuropathy. A threshold lower than 1440 seconds had 93% sensitivity and 100% specificity for class 2 neuropathy. A threshold above 1440 seconds had 100% sensitivity and 99% specificity for class 3 neuropathy. A highly significant (Kendall's tau-b=0.848, p=0.001) correlation was shown between time until complete colour change of the test and Michigan class of neuropathy.

CONCLUSIONS

It appears that the indicator test contributes substantially to the assessment of the staged severity of neuropathy in patients with type 2 diabetes mellitus. There is excellent agreement between the indicator test and the Michigan classification system. These results suggest a role for the indicator test in the assessment of diabetic neuropathy.

An Insertion/Deletion Polymorphism in the alpha2B Adrenoceptor Gene is Associated with Age at Onset of Type 2 Diabetes Mellitus

Alpha2B adrenoceptor (alpha2B-AR) mediates a variety of functions, including insulin secretion. An insertion/deletion (I/D) polymorphism of the alpha2B-AR gene located on chromosome 2 has recently been described. The aim of the present study was to examine if there is a difference in the D allele frequency of alpha2B-AR gene between type 2 diabetic patients and controls, as well as to ascertain whether the D allele confers an increased risk for earlier onset of diabetes. This study included 199 type 2 diabetic patients and 204 age- and sex-matched healthy volunteers. Genotyping of I/D polymorphism was performed by PCR. No significant difference in the D allele frequency was observed between the two groups (22.1% vs. 19.1%, p = 0.409). Among type 2 diabetic patients, however, presence of the D allele was associated with significantly younger age at onset of diabetes (51.4+/-8.6 vs. 59.2+/-9.7 years, p < 0.001). Multiple stepwise linear regression identified alpha2B I/D genotype as an independent predictor of age at onset of DMT2, explaining 14.3% of its variance. This result indicates that the D allele may be implicated in impaired glucose metabolism leading to earlier manifestation of diabetes in predisposed subjects.

Severity of liver echogenicity is correlated to serum c-peptide levels in type 2 diabetic patients

AIM

To investigate the correlation between liver echogenicity and serum C-peptide levels in type 2 diabetic patients treated with oral hypoglycaemic agents.

PATIENTS AND METHODS

The study included 231 type 2 diabetic patients (114 men) with a mean age of 64.3 +/- 6.9 years and a mean diabetes duration of 8.5 +/- 3.2 years. Liver echogenicity was graded by ultrasound examination as follows: Grade 0 (normal liver texture), grade 1 (slight increase of liver echogenicity), grade 2 (moderate increase of liver echogenicity with impaired visualization of intrahepatic vessels and right hemi-diaphragm), grade 3 (marked increase of liver echogenicity with very poor visualization or non-visualization of intrahepatic vessels and right hemi-diaphragm). Serum C-peptide was measured both in fasting state (Fasting C-peptide, FCP) and after glucagon administration (Glucagon-stimulated C-peptide, GCP).

RESULTS

FCP (median; interquartile range) showed a significant difference (p=0.041) between patients with grade 0 (1.9 ng/dl; 1.1-2.7 ng/dl),grade 1 (2.7 ng/dl; 1.9-3.7 ng/dl), grade 2 (4.1 ng/dl; 2.6-5.1 ng/dl) and grade 3 (6.2 ng/dl; 4.6-7.5 ng/dl) liver echogenicity. GCP (median; interquartile range) also differed significantly (p=0.04) between patients with grade 0 (2.6 ng/dl; 1.8-3.3 ng/dl), grade 1 (4.3 ng/dl; 3.3-5 ng/dl), grade 2 (5.8 ng/dl; 4.6-6.9 ng/dl) and grade 3 (8.3 ng/dl; 6.6-9.5 ng/dl) liver echogenicity. In multiple regression analysis, both FCP and GCP showed significant (p < 0.05) positive correlations with waist circumference, triglycerides, WHR and liver echogenicity.

CONCLUSIONS

In type 2 diabetic patients treated with oral hypoglycaemic agents, liver echogenicity shows a significant positive correlation with serum C-peptide levels, both in fasting state and after glucagon administration.

Reproducibility of the New Indicator Test for Sudomotor Function (Neuropad®) in Patients with Type 2 Diabetes Mellitus: Short Communication

The aim of this study was to examine the reproducibility of the new indicator test for sudomotor function (Neuropad) in type 2 diabetic patients. The study included 142 type 2 diabetic patients (70 men) with a mean age of 67.3 +/- 7.6 years and a mean diabetes duration of 14.2 +/- 6.3 years. Sudomotor function was assessed by means of colour change in the indicator test. Each patient was examined twice. Moreover, inter-observer variability was assessed in 60 patients (35 patients with sudomotor dysfunction, 25 patients without sudomotor dysfunction). In the right foot, a highly significant (r = 0.91, p = 0.001) correlation was observed between time until complete colour change of the test on the first (910.7 +/- 431.6 seconds) and second examination (935.8 +/- 440.1 seconds). In the left foot, a highly significant (r = 0.89, p = 0.001) correlation was observed between time until complete colour change of the test on the first (911.6 +/- 430.3 seconds) and second examination (940.5 +/- 441.2 seconds). Reproducibility was excellent both in patients with sudomotor dysfunction (p = 0.001) and in those without sudomotor dysfunction (p = 0.001). Agreement in diagnosis of sudomotor dysfunction between the two examinations was 98 %. Inter-observer reproducibility was excellent (p = 0.001), both in patients with sudomotor dysfunction and in those without sudomotor dysfunction. Intra- and interobserver Coefficient of Variance ranged between 4.1 % and 5.1 %.

CONCLUSIONS

These results indicate that reproducibility of the new indicator test for sudomotor function is excellent in type 2 diabetic patients with or without sudomotor impairment.

Evaluation of a new indicator test for sudomotor function (Neuropad) in the diagnosis of peripheral neuropathy in type 2 diabetic patients

Sudomotor neuropathy is associated with reduction of plantar sweating and contributes to the pathogenesis of diabetic foot ulcers. The aim of the present study was to evaluate the new indicator test for sudomotor function (Neuropad) in the diagnosis of peripheral neuropathy among type 2 diabetic patients. This study included 104 type 2 diabetic patients (51 men) with a mean age of 64.2+/-5.6 years and a mean diabetes duration of 12.8+/-3.7 years. Peripheral neuropathy was diagnosed by means of the Diabetic Neuropathy Index (DNI). Sudomotor neuropathy was assessed by means of colour change in the indicator test. Peripheral neuropathy was diagnosed in 71 patients (68.3 %). Sudomotor neuropathy was diagnosed in 67 patients (94.4 %) with peripheral neuropathy and in 10 patients (30.3 %) without peripheral neuropathy (p=0.0001). Compared with DNI, sensitivity of the indicator test for diagnosing peripheral neuropathy was 94.4 % and specificity was 69.7 %. Overall prevalence of neuropathy was higher using the indicator test (77 patients, 74.0 %) than using the DNI (71 patients, 68.3 %). Time until complete colour change of the indicator test was 23.8+/-6.7 min in patients with peripheral neuropathy and 7.7+/-1.2 min in patients without peripheral neuropathy (p=0.001). Among patients with peripheral neuropathy, time until complete colour change of the indicator test was 14.2+/-1.9 min in those with a DNI value between 2.5 and 4.5, while it was 32.8+/-2.6 min in those with a DNI value between 5 and 8 (p=0.003).

CONCLUSIONS

Use of the new indicator test has a very high sensitivity in detection of diabetic peripheral neuropathy. Sudomotor dysfunction can be demonstrated in a considerable part of patients with normal clinical examination. Time until complete colour change of the indicator test is associated with severity of peripheral neuropathy.

Carotid Plaque Echomorphology and Serum Vascular Endothelial Growth Factor Levels

Neovascularization in atherosclerotic plaques plays an essential role in the progression and rupture of plaques. Vascular endothelial growth factor (VEGF) is an important angiogenic factor. Echomorphologic evaluation of carotid plaques using computer-assisted imaging was found to have a good correlation with the histology of the lesion. The aim of this study was to investigate whether the serum VEGF level could be a determinant of the echomorphology of the carotid plaque. In 28 carotid plaques causing 60-99% stenosis, serum VEGF levels and the mean gray value (MGV) of three-dimensional image of the carotid plaques were measured. A statistically significant inverse correlation was found between serum VEGF concentrations and MGVs (Spearman's correlation coefficient: -0.415, p = 0.028). Our finding indicates that in patients with > or =60% carotid stenosis the serum VEGF levels are associated with the echogenicity of the atherosclerotic plaque.

Umbilical cord serum vascular endothelial growth factor (VEGF) levels in normal pregnancies and in pregnancies complicated by preterm delivery or pre-eclampsia

OBJECTIVES

The aim of this study was to determine whether increased levels of vascular endothelial growth factor (VEGF) are implicated in the pathogenesis of pre-eclampsia and in preterm delivery.

METHODS

Umbilical cord serum VEGF levels from women with uncomplicated term pregnancies (control group, n=24), with pregnancies complicated by pre-eclampsia (n=21), or with preterm delivery (n=29) were compared. Statistical analysis was performed using the Mann-Whitney U-test, the t-test, and Smirnoff-Kolmogorov test.

RESULTS

The mean VEGF concentration was significantly higher in the women with pre-eclampsia than in women from the control group (P<0.01). There were also increased but not significantly higher VEGF concentrations in the preterm delivery group compared with the control group (P=0.16).

CONCLUSIONS

Our study results support previous findings that raised umbilical cord serum VEGF levels might be correlated with the clinical development of pre-eclampsia and, in some circumstances, of preterm delivery.

Serum magnesium levels in non-diabetic offspring of patients with Type 2 diabetes mellitus

A tendency for magnesium deficiency in patients with diabetes mellitus is well established, which probably results from glycosuria-related hypermagnesiuria, nutritional factors or hyperinsulinaemia. Hypomagnesaemia is probably a secondary event but it can also lead to insulin resistance itself. The offspring of patients with Type 2 diabetes mellitus (T2DM) are at increased risk of developing diabetes and several metabolic abnormalities of the disease. The aim of this study was to determine if serum total magnesium levels in healthy offspring of T2DM patients underwent alterations and their relationship to indicators of glucose homeostasis. The sample consisted of two groups: 30 healthy offspring with at least one diabetic parent, and 30 age-matched healthy subjects with no family history of T2DM. None of the participants was on a diet. The mean serum magnesium concentration was 1.070 +/- 0.059 mmol/l in offspring and 1.075 +/- 0.084 mmol/l in controls (p=0.66). There was no statistically significant correlation between serum magnesium levels and parameters of glucose homeostasis in offspring. Our results support the conclusion that total serum magnesium probably has no relationship with the main indicators of glucose homeostasis in offspring of T2DM patients and is not likely to be a fundamental risk factor for the development of insulin resistance.

Hypoxia inducible factor 1alpha and 2alpha overexpression in inflammatory bowel disease

AIMS

Hypoxia inducible factors 1alpha and 2alpha (HIF1alpha and HIF2alpha) are hypoxia regulated transcriptional factors, which control the expression of a variety of genes responsible for angiogenesis, glycolysis, and the inhibition of apoptosis. Because angiogenesis and tissue regeneration are integral components of the inflammatory process, this study was designed to investigate the role of HIFalpha molecules in inflammatory bowel disease.

METHODS

Surgical specimens from patients with active ulcerative colitis (UC) and Crohn's disease (CD) were assessed immunohistochemically for HIF1alpha and HIF2alpha reactivity, and the expression of these molecules was compared with the expression of the angiogenic factors thymidine phosphorylase (TP), vascular endothelial growth factor (VEGF), and VEGF-KDR activated vasculature. The vascular density of the lesions was also assessed using anti-CD31 immunostaining.

RESULTS

HIF1alpha was expressed focally (epithelial cells, stromal fibroblasts, and myocytes) in both UC and CD, whereas HIF2alpha was expressed focally in UC and diffusely in CD. TP expression was uniformly positive in both diseases. VEGF expression was absent in CD, and weakly positive in UC. The VEGF-KDR reactivity of the submucosal vasculature was only slightly increased in UC and CD compared with normal tissue. The inflammatory cells stained with HIF2alpha and TP in all cases, but the reactivity was generalised in CD and focal in UC. In both diseases, vascular density was significantly higher than that seen in normal tissue.

CONCLUSIONS

The discordant expression of HIF2alpha and VEGF in CD suggests an inherent deficiency of the intestine to respond to various stresses by the induction of VEGF. This finding should be investigated further.

Tumour necrosis factor-alpha levels in non-diabetic offspring of patients with type 2 diabetes mellitus

Tumour necrosis factor-alpha (TNF-alpha) is considered to be involved in the insulin resistance of type 2 diabetes mellitus. The offspring of patients with type 2 diabetes mellitus are at increased risk of developing diabetes and several metabolic abnormalities, but the underlying defects responsible are not known. We studied serum TNF-alpha levels in 30 healthy non-diabetic offspring of type 2 diabetic parents (group A), and the relationship between TNF-alpha levels and variables associated with insulin resistance and diabetes. For comparison, 30 healthy offspring of non-diabetic parents (group B) were also studied. The median serum concentration of TNF-alpha was significantly higher in group A than in group B, 3.5 pg/ml compared with 2.0 pg/ml, respectively. The individuals of group A also had significantly elevated levels of glycosylated haemoglobin, fasting glucose, glucose 2 h after an oral glucose tolerance test and triglycerides. We conclude that serum TNF-alpha concentration is significantly elevated in non-diabetic offspring of type 2 diabetics and this may predict later impairment of insulin action in these individuals.

Interleukin-6 levels in umbilical artery serum in normal and abnormal pregnancies

OBJECTIVE

The aim of our study was to determine the correlation of abnormal umbilical artery interleukin-6 levels with pregnancies complicated by preterm delivery and pre-eclampsia.

METHOD

Cord serum (umbilical artery) was collected at delivery by cesarean section or spontaneous delivery. Samples were retrieved from patients with normal and abnormal pregnancies. Patients were divided into three groups: group 1, a control group of samples from uncomplicated pregnancies (n = 24); group 2, patients with pre-eclampsia (n = 21); and group 3, patients having had preterm delivery (n = 29). Interleukin-6 was measured by bioassays. Statistics were performed with the Mann-Whitney U-, Student's t- and the Kruskal-Wallis tests.

RESULTS

Interleukin-6 levels in women with preterm delivery were statistically higher compared to those of normal pregnancies (P < 0.05) and lower in the cord serum of pre-eclamptic when compared to those of normal pregnancies (P < 0.05).

CONCLUSION

In conclusion, we believe that further investigations could elucidate the role of this pleiotropic cytokine in both, normal and pathologic reproductive biology, and determine the clinical utility of IL-6 measurements in obstetric practice.

Retardation by aminoguanidine of development of albuminuria, mesangial expansion, and tissue fluorescence in streptozocin-induced diabetic rat

This study evaluated the relationship between the development of fluorescence related to advanced glycosylation end products (AGEs) in the kidney and experimental diabetic nephropathy over a 32-wk period. Control, untreated diabetic, and aminoguanidine-treated diabetic rats were followed for 32 wk with eight weekly measurements of urinary albumin excretion. After 32 wk, collagen-related fluorescence in aorta and kidney (whole kidney, isolated glomeruli, and renal tubules) and glomerular ultrastructure were evaluated. Diabetes was associated with a significant increase in collagen-related fluorescence in the aorta and kidney. Aminoguanidine prevented the increases in collagen-related fluorescence in aorta, isolated glomeruli, and renal tubules but not in whole kidney. Diabetes was associated with increased albuminuria, fractional mesangial volume, and glomerular basement membrane (GBM) thickness. Aminoguanidine attenuated the rise in albuminuria and prevented mesangial expansion without influencing GBM thickness in diabetic rats. The concomitant changes in collagen-related fluorescence, albuminuria, and mesangial expansion with aminoguanidine therapy are consistent with the hypothesis that AGEs may play a role in the development of diabetic nephropathy.

Nephropathy in model combining genetic hypertension with experimental diabetes. Enalapril versus hydralazine and metoprolol therapy

We compared the effects of the angiotensin-converting enzyme inhibitor enalapril and a conventional antihypertensive regimen (hydralazine and metoprolol) on kidney function, albuminuria, and glomerular ultrastructure in hypertensive diabetic and nondiabetic rats. Diabetes was induced with streptozocin at 8 wk of age in spontaneously hypertensive (SHR) rats. Antihypertensive drugs were administered in drinking water from the time of induction of diabetes in all groups. Blood pressure reduction was equal in the diabetic and nondiabetic SHR rats receiving either enalapril or hydralazine plus metoprolol. In diabetic SHR rats, there was a rise in serum creatinine after 32 wk, which did not occur in diabetic rats treated with either antihypertensive regimen or in nondiabetic rats. Both drug regimens reduced albuminuria in diabetic and nondiabetic SHR rats to a similar degree. Enalapril and the combination of hydralazine and metoprolol were associated with decreased glomerular basement membrane thickness and glomerular volume in diabetic and nondiabetic SHR rats without significant effect on fractional mesangial volume. Thus, antihypertensive therapy retards the development of albuminuria, glomerular basement membrane thickening, and glomerular hypertrophy in the rat in the presence or absence of diabetes. No specific benefit of angiotensin-converting enzyme inhibition was observed in these hypertensive models of nephropathy. Human studies comparing the effects of different classes of antihypertensive drugs on kidney function, proteinuria, and glomerular morphology are warranted.