Plasma cytokines and future risk of non-Hodgkin lymphoma (NHL): a case-control study nested in the Italian European Prospective Investigation into Cancer and Nutrition.

BACKGROUND: Recently, biological markers related to the immune system such as cytokines have been studied to further understand the etiology of non-Hodgkin Lymphoma (NHL). However, to date, there are no studies that have studied cytokine levels prospectively in relation to NHL risk in the general population. METHODS: Using bead-based immunoassays, plasma levels of 11 cytokines, 4 chemokines, and 1 adhesion molecules were measured in prediagnostic blood samples of 86 NHL cases and 86 matched controls (average time between blood collection and diagnosis, 4.5 y). Conditional logistic regression adjusted for body mass index and alcohol consumption was used to analyze the association between individual plasma cytokine levels and the risk of developing NHL. RESULTS: In multivariate models, excluding cases diagnosed within 2 years after inclusion, we observed a significant association for interleukin 2 (IL2; P trend = 0.004), interferon (IFN)-gamma (P trend = 0.05), and intercellular adhesion molecule (ICAM) (P trend = 0.04). Subanalyses of B-cell NHL patients showed a significant association with IL2 (P trend = 0.003), tumor necrosis factor-alpha (TNF-alpha; P trend = 0.03), and ICAM (P trend = 0.04) and a borderline association with IL5 (P trend = 0.07) and IFN-gamma (P trend = 0.08). CONCLUSIONS: The results of this study suggest, in a prospective setting, a possible association between plasma levels of IL2, ICAM, IFN-gamma, and TNF-alpha with NHL risk and provide some evidence that risk of NHL might be related to a downregulation of T helper 1 cytokines. IMPACT: Identification of subtle changes in immune response regulation quantified by plasma cytokine levels possibly provides new insights in the etiology of NHL.

Functional characterization of alloreactive T cells identifies CD25 and CD71 as optimal targets for a clinically applicable allodepletion strategy.

Immunotherapy with allodepleted donor T cells (ADTs) improves immunity after T cell-depleted stem cell transplantation, but infection/relapse remain problematic. To refine this approach, we characterized the expression of surface markers/cytokines on proliferating alloreactive T cells (ATs). CD25 was expressed on 83% of carboxyfluorescein diacetate succinimidyl ester(dim) ATs, confirming this as an excellent target for allodepletion. Seventy percent of CD25(-) ATs expressed CD71 (transferrin receptor), identifying this as a novel marker to target ATs persisting after CD25 depletion. Comparison of residual alloreactivity after combined CD25/71 versus CD25 immunomagnetic depletion showed enhanced depletion of alloreactivity to host with CD25/71 depletion in both secondary (2 degrees) mixed lymphocyte reactions (P < .01) and interferon-gamma enzyme-linked immunospot assays (P < .05) with no effect on third-party responses. In pentamer/interferon-gamma enzyme-linked immunospot assays, antiviral responses to cytomegalovirus, Epstein-Barr virus, and adenovirus were preserved after CD25/71 allodepletion. CD25/71 ADTs can be redirected to recognize leukemic targets through lentiviral transfer of a chimeric anti-CD19zeta T-cell receptor. Finally, we have established conditions for clinically applicable CD25/71 allodepletion under European Union Good Manufacturing Practice conditions, resulting in highly effective, reproducible, and selective depletion of ATs (median residual alloreactivity to host in 2 degrees mixed lymphocyte reaction of 0.39% vs third-party response of 62%, n = 5). This strategy enables further clinical studies of adoptive immunotherapy with larger doses of ADTs to enhance immune reconstitution after T cell-depleted stem cell transplantation.

Neutrophil-mediated innate immune resistance to mycobacteria.

Neutrophils contain antimicrobial peptides with antituberculous activity, but their contribution to immune resistance to tuberculosis (TB) infection has not been previously investigated to our knowledge. We determined differential white cell counts in peripheral blood of 189 adults who had come into contact with patients diagnosed with active TB in London, United Kingdom, and evaluated them for evidence of TB infection and capacity to restrict mycobacterial growth in whole-blood assays. Risk of TB infection was inversely and independently associated with peripheral blood neutrophil count in contacts of patients diagnosed with pulmonary TB. The ability of whole blood to restrict growth of Mycobacterium bovis bacille Calmette Guérin and Mycobacterium tuberculosis was impaired 7.3- and 3.1-fold, respectively, by neutrophil depletion. In microbiological media, human neutrophil peptides (HNPs) 1-3 killed M. tuberculosis. The neutrophil peptides cathelicidin LL-37 and lipocalin 2 restricted growth of the organism, the latter in an iron-dependent manner. Black African participants had lower neutrophil counts and lower circulating concentrations of HNP1-3 and lipocalin 2 than south Asian and white participants. Neutrophils contribute substantially to innate resistance to TB infection, an activity associated with their antimicrobial peptides. Elucidation of the regulation of neutrophil antimicrobial peptides could facilitate prevention and treatment of TB.

Altered monocyte cyclooxygenase response to lipopolysaccharide in type 1 diabetes.

Type 1 diabetes is caused by adaptive immune responses, but innate immunity is important because monocytes infiltrate islets. Activated monocytes express cyclooxygenase (COX)-2, promoting prostaglandin-E(2) (PGE(2)) secretion, whereas COX-1 expression is constitutive. We aimed to define monocyte COX expression in type 1 diabetes basally and after lipopolysaccharide (LPS) stimulation. Isolated CD14(+) monocytes were analyzed for COX mRNA and protein expression from identical twins (discordant for type 1 diabetes) and control subjects. Basal monocyte COX mRNA, protein expression, and PGE(2) secretion were normal in type 1 diabetic subjects. After LPS, twins and control subjects showed a COX mRNA isoform switch with decreased COX-1 mRNA (P < 0.01), increased COX-2 mRNA (P < 0.01), and increased COX-2 protein expression (P < 0.01). Compared with control subjects, both diabetic and nondiabetic twins showed greater LPS-induced downregulation of monocyte COX-1 mRNA (P = 0.02), reduced upregulation of COX-2 mRNA and protein (P < 0.03), and greater inhibition by the COX-2 inhibitor di-isopropylfluorophosphate (DFP) of monocyte PGE(2) (P < 0.007). We demonstrate an alteration in monocyte COX mRNA expression as well as monocyte COX-2 and PGE(2) production after LPS in type 1 diabetic patients and their nondiabetic twins. Because COX-2 response to LPS is proinflammatory, an inherited reduced response would predispose to chronic inflammatory diseases such as type 1 diabetes.

Local CD11c+ MHC class II- precursors generate lung dendritic cells during respiratory viral infection, but are depleted in the process.

Increases in numbers of lung dendritic cells (DC) observed during respiratory viral infections are assumed to be due to recruitment from bone marrow precursors. No local production has been demonstrated. In this study, we isolated defined populations of murine lung cells based on CD11c and MHC class II (MHC II) expression. After culture for 12 days with GM-CSF, we analyzed cell numbers, DC surface markers, and Ag-presenting capacity. Only CD11c+ MHC II- cells from naive mice proliferated, yielding myeloid DC, which induced Ag-specific proliferation of naive T cells. After respiratory syncytial virus (RSV) infection, numbers of pulmonary CD11c+ MHC II- precursor cells were significantly reduced and DC could not be generated. Moreover, RSV infection prevented subsequent in vivo expansion of pulmonary DC in response to influenza infection or LPS treatment. These results provide direct evidence of local generation of fully functional myeloid DC in the lung from CD11c+ MHC II(-) precursor cells that are depleted by RSV infection, leading to an inability to expand lung DC numbers in response to subsequent viral infection or exposure to bacterial products. This depletion of local DC precursors in respiratory viral infections may be important in explaining complex interactions between multiple and intercurrent pulmonary infections.

Identical twins discordant for type 1 diabetes show a different pattern of in vitro CD56+ cell activation.

BACKGROUND: Recent studies in animal models indicate a role for natural killer (NK) cells in the protection against type 1 diabetes. In humans, a reduction of NK cell numbers has been reported in identical twins discordant for type 1 diabetes, irrespective of whether they have the disease. Here we have tested whether the activation and expansion of human NK cells with lipopolysaccharide (LPS) reveals differences between these twins. METHODS: Proportions of CD56(+) NK cells and T-cells and Va24Vb11(+) NK-T cells from diabetic and non-diabetic twins was assessed before and after activation using flow cytometry. NK receptor usage was monitored by PCR and flow cytometry. RESULTS: The profile of the expressed Killer Cell immunoglobulin-like receptor (KIR) repertoire (using mRNA) in freshly isolated NK cells was identical in pairs of identical twins, despite marked variation among individual twins as well as controls. Basal numbers of CD56(+) and CD94(+) (CD3(-) and CD3(+)) cells and Valpha24(+)Vbeta11(+) NK-T cells were similarly strongly correlated between identical twins (p < 0.006 for all correlations). Following LPS stimulation, the pattern of KIR mRNA expression remained unaltered in twins and the proportion of NK cells and Valpha24(+)Vbeta11(+) NK-T cells remained correlated between pairs of twins. However, there was a significant reduction in the proportion of CD56(+) cells and CD94(+) cells (whether defined as CD3(-) or CD3(+)) responding to LPS in the diabetic compared to the non-diabetic twin (p = 0.031 and 0.025, respectively). CONCLUSION: This reduction in NK cell expansion in response to LPS in patients with type 1 diabetes is consistent with a non-genetically determined alteration in the innate immune response either predisposing to or resulting from the disease.