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Reduced natural killer cell activity and IL-2 production in malnourished cancer patients.

Natural killer (NK) cell activity was measured in the peripheral blood mononuclear cells (PBMC) from malnourished (MN) and well-nourished (WN) cancer patients and in healthy controls. A marked depression of NK activity was observed in MN cancer patients with moderate protein-calorie malnutrition (PCM), but not in WN cancer patients nor in the healthy controls. The depression of NK activity did not correlate with the localisation of the tumour, patient's age or body weight reduction. The defective NK activity of PBMC from MN cancer patients was restored to normal by rIL-2, but not by alfa-rIFN. Parenteral nutrition of MN patients with the proper amount of proteins and calories quickly corrected the depressed NK activity, indicating a central role of malnutrition in the genesis of their immune disfunction. PBMC from MN cancer patients produced lower amounts of IL-2, as compared with healthy controls, when stimulated in vitro; the most frequently affected were the responses to recall antigens such as influenza virus vaccine (FLU), while those to allogeneic PBMC (ALLO) and phytohaemagglutinin (PHA) were less affected. However, for each patient the ability to produce IL-2 in vitro did not correlate with NK activity, thus showing how the impairment of NK activity is not subsequent to a decreased production of endogenous IL-2. In summary, it can be concluded that malnutrition, rather than malignancy, plays a major role in the immune dysfunction of cancer patients.

Adult↗

Pertussis toxin pretreatment alters the in vivo cell division behaviour and survival of B lymphocytes after intravenous transfer.

Pertussis toxin (PT), produced by the causative agent of whooping cough, Bordetella pertussis, contributes to the immune dysfunction seen in infected patients. Treatment of laboratory animals with purified toxin reproduces many of the biological effects exhibited in the disease state, which include lymphocytosis, adjuvant effects for IgE secretion and delayed-type hypersensitivity reactions. In previous studies, we have demonstrated that PT pretreatment of intravenously transferred lymphocytes not only results in them being held up in the blood, but also causes a profound alteration in their positioning within the spleen. Pertussis toxin pretreated lymphocytes fail to traverse the layer of marginal zone macrophages encircling the white pulp, resulting in their exclusion from the lymphoid area of the spleen. Using a novel flow cytometric assay of cell division, the studies presented here show that a significant proportion of B, but not T, lymphocytes underwent proliferation after intravenous transfer of donor splenic lymphocytes to syngeneic recipients. This proliferation was markedly reduced by PT pretreatment of lymphocytes before transfer. In contrast, the in vitro proliferative responses of B lymphocytes to anti-IgM, LPS and antibody engagement of CD40 were unimpaired by exposure to the same levels of PT. Furthermore, the rate of in vivo decay of transferred B cells was accelerated by pretreatment with PT. Together, these data suggest PT impairs the receipt of signals which promote survival and proliferation of B cells, due to altered recirculation and positioning of lymphocytes.

Adoptive Transfer↗

Autophosphorylation at serine 1987 is dispensable for murine Atm activation in vivo.

The ATM (ataxia telangiectasia mutated) protein kinase is activated under physiological and pathological conditions that induce DNA double-strand breaks (DSBs). Loss of ATM or failure of its activation in humans and mice lead to defective cellular responses to DSBs, such as cell cycle checkpoints, radiation sensitivity, immune dysfunction, infertility and cancer predisposition. A widely used biological marker to identify the active form of ATM is the autophosphorylation of ATM at a single, conserved serine residue (Ser 1981 in humans; Ser 1987 in mouse). Here we show that Atm-dependent responses are functional at the organismal and cellular level in mice that express a mutant form of Atm (mutation of Ser to Ala at position 1987) as their sole Atm species. Moreover, the mutant protein does not exhibit dominant-negative interfering activity when expressed physiologically or overexpressed in the context of Atm heterozygous mice. These results suggest an alternative mode for stimulation of Atm by DSBs in which Atm autophosphorylation at Ser 1987, like trans-phosphorylation of downstream substrates, is a consequence rather than a cause of Atm activation.

Animals↗

Analyzing phosphoinositides and their interacting proteins.

Phosphorylated derivatives of phosphatidylinositol (PtdIns), known as phosphoinositides (PIs), are essential regulators of nuclear functions, cytoskeletal dynamics, cell signaling and membrane trafficking. These lipids are found on the cytosolic face of intracellular membranes but can also be detected in membrane-free regions of the nucleoplasm. Their downstream effectors include several proteins that contain various PI-specific domains. Because impaired PI metabolism is associated with disorders such as cancer, cardiovascular disease and immune dysfunction, there is currently great interest in studying PIs and their metabolic enzymes. Here we describe strategies and techniques for quantitative and qualitative measurement of PIs, for characterization of specific PI-binding proteins and for determination of PI kinase and phosphatase activities in vitro and in vivo.

Animals↗

Restoration of T and NK cell function in GM-CSF mobilized stem cell products from breast cancer patients by monocyte depletion.

Rapid immune reconstitution is observed following autologous peripheral blood stem cell transplantation (PSCT) as compared to autologous bone marrow transplantation (ABMT), although it is depressed compared to that observed in normal individuals. The immune dysfunction occurs despite the restoration of normal lymphoid cell numbers and may be associated with the immunologic characteristics of the infused peripheral blood stem cell (PSC) product. We report herein that the in vitro T cell proliferation and NK activity in PSC products of breast cancer patients are significantly increased following the removal of CD14+ monocytes (33 +/- 2% of the PSC product) by carbonyl iron magnetic cell isolation (CI). In vitro expansion of PSC cells cultured for 7-21 days in the presence of interleukin-2 (IL-2) is also significantly increased by depletion of the phagocytic cells. The PHA and IL-2 mitogenic responses, as well as NK activity of the expanded cells, was also significantly increased by the depletion of the phagocytes. In summary, the depletion of phagocytic monocytes from PSC products restores the proliferative and functional properties of T and NK lymphocytes and may facilitate adoptive cellular therapy, as well as rapid immunologic reconstitution post-PSCT.

Breast Neoplasms↗

Tularemia--an unusual cause of a solitary pulmonary nodule in the post-transplant setting.

We report a case of tularemia presenting as a solitary pulmonary nodule following syngeneic PBSC transplant. Seven months after undergoing a syngeneic PBSC transplant for AML, our patient presented with fever without localizing signs. Chest X-ray revealed a solitary pulmonary nodule. Culture of a CT guided needle aspiration revealed Francisella tularensis. The patient was successfully treated with ciprofloxacin. His fever resolved and clearance of the nodule was documented on a CT scan 2 months after diagnosis and initiation of treatment. To our knowledge, this is the only reported case of tularemia occurring in the post-transplant setting. The possible relationship between transplant-induced immune dysfunction and the occurrence of this rare infection is discussed.

Anti-Infective Agents↗

Recovery of lymphocyte and dendritic cell subsets after autologous CD34+ cell transplantation.

Following high-dose chemotherapy (HDC) and peripheral blood progenitor cell transplantation (PBPCT), there are profound changes in leukocyte homeostasis and the immune system is compromised. Transplantation of purified CD34+ cells may further compromise immune recovery because the grafts are depleted of mature immune cells. However, a detailed monitoring of immune cell reconstitution has not been done. We monitored blood levels of antigen-presenting cells (APC) and of lymphocytes by multi-color flow cytometry at different times post CD34+ PBPCT. We found a rapid normalization of circulating levels of the antigen-presenting CD11c+ dendritic cells (defined as lineage- HLA-DR+ CD11c+ cells). There was a slight over-representation of lin- DR+ CD11c- cells at day 42 post transplantation suggesting that the composition of the APC population might be affected. Normal levels of total T, B and NK lymphocytes were rapidly achieved but the composition of the T cell population was abnormal. Patients had elevated levels of CD8+ T cells at early times and a persistent reduction in levels of naive CD8+ T cells (CD8+ CD4- CD45RA+ CD27+) and of naive CD4+ T cells (CD4+CD3+ CD8- CD45RA+). Thus, we found a rapid recovery of DC after CD34+ PBPCT but the specific numerical defects in naive T cells are likely to be a major cause of immune dysfunction in the patients. Bone Marrow Transplantation (2000) 25, 1249-1255.

Adult↗

Adjuvant interleukin-12 gene therapy for the management of colorectal liver metastases.

In humans, no efficient treatment exists not only against multifocal liver metastases (LM) but also against recurrent microscopic liver metastases within the liver remnant following curative liver resection. Furthermore, in nonmultifocal LM, partial liver resection could be performed, but in more than 50% of the patients, tumor recurrence within liver remnant is observed, partly due to the growth of dormant cancer cells in the setting of postoperative host immune dysfunction. We investigated the therapeutic potential of interleukin-12 (IL-12) immuno-gene therapies in these experimental models under total vascular exclusion (TVE) of the liver. In rats with multiple LM of DHDK12 colon cancer cells, we observed a significant reduction in tumor volume after retroviral-mediated gene transfer of either herpes simplex virus thymidine kinase (HSV1-TK) and ganciclovir (GCV) administration, or IL-12. Combined treatment with HSV1-TK/GCV and IL-12 resulted in improved tumor volume reduction and even survival. In rats with recurrent microscopic DHDK12 LM established after partial liver resection, we observed significantly decreased recurrent tumor volumes and increased survival after retroviral-mediated IL-12 gene transfer. In both settings, immunohistological analysis revealed that IL-12 immuno-gene therapy was accompanied by an infiltration of CD8+ T lymphocytes within the tumors. Altogether, our results suggest that IL-12 adjuvant gene therapy could improve the management of patients with either resectable or unresectable LM.

Animals↗

ATM and ataxia telangiectasia.

Ataxia telangiectasia (AT) has long intrigued the biomedical research community owing to the spectrum of defects that are characteristic of the disease, including neurodegeneration, immune dysfunction, radiosensitivity and cancer predisposition. Following the identification of mutations in ATM (ataxia telangiectasia, mutated) as the underlying cause of the disease, biochemical analysis of this protein kinase has shown that it is a crucial nexus for the cellular response to DNA double-stranded breaks. Many ATM kinase substrates are important players in the cellular responses that prevent cancer. Accordingly, AT is a disease that results from defects in the response to specific types of DNA damage. Thus, although it is a rare neurodegenerative disease, understanding the biology of AT will lead to a greater understanding of the fundamental processes that underpin cancer and neurodegeneration.

Ataxia Telangiectasia↗

Glutathione S-transferase genotypes in systemic sclerosis and their association with clinical manifestations in early disease.

The glutathione S-transferases (GSTs) are a family of enzymes involved in limiting oxidative damage to tissues. Null alleles for one or more of the GST enzymes, especially GSTM1, reportedly occur more frequently in patients with Sjögren's syndrome and systemic lupus erythematosus who possess certain autoantibodies. Because systemic sclerosis (SSc) is a disease in which oxidative damage has been hypothesized to contribute both to immune dysfunction and tissue damage, we sought to determine if patients from a multi-ethnic cohort of SSc patients with early disease (< or =5 years) were more likely than ethnically-matched normal controls to have null alleles for GSTM1 (M1) and/or GSTT1 (T1), and if the null allele status correlated with any major disease features. The data show that while M1 and T1 null genotypes were not significantly increased in SSc compared to ethnically matched controls, their frequencies (especially T1 nulls) were significantly higher among SSc patients with hypertension and pulmonary involvement. This suggests that GST genotype may be a genetic factor that contributes to clinical disease expression in SSc.

Genotype↗

Linkage analysis of the genetic determinants of T-cell IL-4 secretion, and identification of Flj20274 as a putative candidate gene.

The activation-induced differentiation of naive CD4+ T cells generates functionally divergent type 1 helper T cells (Th1) or type 2 helper T cells (Th2) effector cell populations, characterized by secretion of Interferon (IFN)-gamma or Interleukin (IL)-4, respectively. Inappropriate generation of Th subsets may contribute to immune dysfunction. The decision to generate Th1/Th2 lineages is critically regulated by cytokines, such that IL-12 induces Th1 differentiation, while IL-4 induces Th2 differentiation. Genetic factors influence the pathway of Th differentiation, as displayed by the preferential generation of divergent Th populations by different inbred strains of mice. We employ two complementary genetic techniques to identify genes that regulate the default IL-4 secretion profiles of T cells from BALB/c and B6 mice. We performed a genome-wide linkage analysis of the progeny of a backcross between BALB/c and B6 mice to identify three loci, T-cell secretion of interleukin-4 (Tsi)1-3, on chromosomes 7, 19 and 15, respectively, which regulate in vitro T-cell IL-4 production. We have also employed mRNA representational difference analysis to isolate a gene, Flj20274, which is differentially expressed in T cells that secrete high levels of IL-4. Significantly, Flj20274 was mapped to the point of peak linkage within Tsi1 and is a strong candidate for Tsi1.

Animals↗

Genetics of inflammatory bowel disease.

1. The aetiology of the chronic inflammatory bowel diseases, Crohn's disease and ulcerative colitis, is uncertain. Studies of specific environmental factors and immune dysfunction have provided little insight into disease pathogenesis. 2. Concordance rates in twin pairs and siblings provide strong evidence that genetic factors are important in disease pathogenesis. In Oxford, information was obtained from 433 adult patients with Crohn's disease. Compared with the prevalence in the general population, the relative risks in siblings of patients with Crohn's disease calculated from these data were respectively 36.5 for Crohn's disease, 16.6 for ulcerative colitis and 24.7 for inflammatory bowel disease. 3. Clinical patterns of disease were compared in members of over 250 multiply affected families with inflammatory bowel disease. A high degree of concordance for many characteristics was noted (disease type, extent, extra-intestinal manifestations). However, in 77 affected parent-child pairs, the median age of onset in the parents was significantly higher than in offspring (P < 0.0001). These data reflect the results from other studies throughout the world, and are consistent with the phenomenon of genetic anticipation. 4. A detailed study investigating the contribution of the major histocompatibility complex was undertaken. Eighty-three affected sibling pairs were involved in a linkage analysis study; 348 patients with inflammatory bowel disease and 472 controls were involved in a detailed allelic association study. These data provide evidence that the major histocompatibility complex is an important determinant in ulcerative colitis, but not in Crohn's disease. 5. Cytokine genes are important candidate genes in inflammatory bowel disease. Allelic association study was performed to investigate the contribution of the gene encoding the interleukin-1 receptor antagonist and tumour necrosis factor-alpha. These data do not suggest that these genes encode important determinants of disease susceptibility in inflammatory bowel disease. 6. A two-stage genome-wide search for susceptibility loci in inflammatory bowel disease was performed involving 186 affected sibling pairs. The data provide strong evidence for the model of Crohn's disease and ulcerative colitis as related polygenic disorders. Loci on chromosomes 3, 7 and 12 were linked to inflammatory bowel disease overall, whereas loci on chromosomes 2 and 6 were linked only in ulcerative colitis. Linkage with chromosome 16 was noted in Crohn's disease only. Fine mapping of these susceptibility loci is in progress, and may lead to gene identification with attendant clinical benefits.

Age of Onset↗

Rosai-Dorfman disease complicated by autoimmune haemolytic anaemia: case report and review of a multisystem disease with cutaneous infiltrates.

We report a patient with sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) who presented with widespread nodal and extranodal involvement affecting the skin, orbits and nasal sinuses, complicated by the development of autoimmune haemolytic anaemia. The aetiology and pathogenesis of this multisystem disorder are unknown but are thought to represent a reactive histiocytic process to an infective agent rather than a neoplastic or other primary condition. Prognosis is generally good but clinical or laboratory evidence of immune dysfunction tends to predict a poorer outcome. We describe the clinical course of the patient and review the literature on this disease.

Adult↗

Variable expression of CD3-zeta and associated protein tyrosine kinases in lymphocytes from patients with myeloid malignancies.

In myeloid malignancies, T-cell and NK function has been shown to deteriorate with transformation from pre-leukaemia to advanced disease. Immune dysfunction in solid tumours has been attributed to abnormal signal transduction, possibly through altered expression of intracellular components of the TCR/CD3 complex (e.g. CD3-zeta), receptors on NK cells and their associated protein tyrosine kinases (PTKs; p56lck, p59fyn and ZAP-70). Using a flow cytometric method to detect dual-expression of surface proteins and intracellular components of the TCR/CD3 complex, we have studied 46 patients with myeloid malignancies. CD3-zeta expression was abnormal in 64% of patients, and was more prominent in those with advanced disease. Three patients with reduced CD3-zeta were analysed both pre- and post-treatment, and recovery of CD3-zeta expression was associated with successful remission induction (expression of PTKs was variable and reduced levels were seen all disease stages). The results of this study suggest that loss of signalling proteins is not a result of direct contact of leukaemic cells with lymphocytes per se or the extent of the leukaemia burden, but to a specific property of some myeloid malignancies, which is more frequently acquired with greater malignant transformation.

Adult↗

Infections in adults undergoing unrelated donor bone marrow transplantation.

This study retrospectively reviews infections over a 7-year period in 60 consecutive adults (median age 25 years) undergoing their first unrelated donor bone marrow transplant (UD-BMT). T-cell depletion was employed in 93%. More than half the patients had one or more severe, potentially life-threatening, infections. There was a high incidence of invasive fungal infections (Aspergillus 17, Candida four), despite the use of itraconazole or amphotericin prophylaxis. Ten Aspergillus infections occurred beyond 100 d. Two patients (11%) with invasive aspergillosis survived. Clustering of infections was noted, with invasive fungal infections significantly associated with bacteraemias (OR 3.73, P=0.06) and multiple viral infections (OR 4.25, P=0.05). There were 21 severe viral infections in 16 patients, with CMV disease occurring in four patients only; viral pneumonitis was predominantly due to 'community respiratory' viruses. Most early bacteraemias (68%) were due to Gram-positive organisms. The majority of episodes of Gram-negative sepsis were caused by non-fastidious non-fermentative bacteria, such as Pseudomonas spp. and Acinetobacter spp., historically regarded as organisms of low pathogenicity. In patients with successful engraftment and minimal graft-versus-host disease, late infections suggestive of continued immune dysfunction (shingles, recurrent lower respiratory infections, Salmonella enteritis and extensive warts) were common.

Adolescent↗

Protein assays for diagnosis of Wiskott-Aldrich syndrome and X-linked thrombocytopenia.

Mutations in the gene encoding the Wiskott-Aldrich syndrome protein (WASp) give rise to Wiskott-Aldrich syndrome (WAS), a condition that exhibits a wide spectrum of clinical severity. Patients may develop mild thrombocytopenia or suffer from a wide range of associated disorders including eczema, immune dysfunction, autoimmune disease and malignancy. The clinical diagnosis of Wiskott-Aldrich syndrome (WAS) can be difficult and is usually supported by the detection of WASp gene mutations using genetic analysis. Recently, protein-based assays have been used to demonstrate the absence of WASp in patients known to have WASp gene mutations. We have now reversed this approach and report on the use of immunoblot assays to rapidly diagnose WAS in 13 patients. There was a complete absence of WASp in 10 out of 13 patients and an abnormal protein form was detected in the remaining three patients. In all cases, subsequent genetic analysis confirmed the presence of a WASp gene mutation. We believe that protein-based assays should be employed as the first line of investigation in the diagnosis of WAS spectrum disorders.

Aged↗

Clinical relevance of balance between type 1 and type 2 immune responses of lymphocyte subpopulations in aplastic anaemia patients.

Immune dysfunction, which leads to the suppression of haemopoiesis by cytokines that are secreted by activated T lymphocytes, is considered to play a key role in the pathogenesis of acquired aplastic anaemia (AAA). We investigated the intracytoplasmic expression of type-1 [interferon gamma (IFN-gamma), interleukin (IL)-2] and type-2 (IL-4, IL-10) cytokines in CD4+ and CD8+ T cells before and after in vitro activation in 16 patients with AAA and 17 normal controls. Untreated or refractory patients had a significantly higher proportion of unstimulated CD4+ and CD8+ T cells that produced IFN-gamma and IL-2 whereas the IL-4 and IL-10 producing T cells did not differ from that of controls, resulting in a shift of IFN-gamma/IL-4 ratio towards a type-1 response. Patients in remission had also increased proportion of IFN-gamma-producing unstimulated CD4+ and CD8+ cells, with a parallel rise of IL-4- and IL-10-producing cells and normal IFN-gamma/IL-4 ratio. These data indicate that, in newly diagnosed and refractory patients with AAA, CD4+ cells are polarized towards a type-1 response that in turn leads to activation of cytotoxic CD8+ cells and finally to haemopoietic stem cell destruction. The type-1 response persists in patients in remission although this effect is compensated by the increase of IL-4 and IL-10 production.

Adult↗

Hepatitis C is more severe in drug users with human immunodeficiency virus infection.

Drug users with chronic hepatitis C virus (HCV) infection are frequently co-infected with human immunodeficiency virus-1 (HIV-1), but it is still not clear whether HIV-1 worsens the natural history of hepatitis C. To investigate this, we conducted a multicentre observational study in 163 drug addicts with histologically documented hepatitis C, 92 of whom were also infected with HIV-1: 25 (27%) were CDC stage II, 53 (58%) were CDC stage III and 14 (15%) were CDC stage IV. Eighty-eight (54%) patients had chronic hepatitis (CH) with minimal activity, 28 (17%) had CH with moderate activity, 40 (25%) had CH with severe activity and seven (4%) had active cirrhosis. Twenty-one HIV-negative patients and 15 HIV-positive patients admitted to alcohol abuse (29% vs 16%, P=0.0665). Liver disease was more severe in HIV-positive patients than in HIV-negative ones (P=0.0198): 34 HIV-positive patients and 13 HIV negatives had severe CH and cirrhosis. These two severe liver diseases were seen more often in HIV-positive patients with a history of alcohol abuse than in HIV-negative patients (10 out of 16 vs seven out of 21). Age, alcohol abuse and distribution of the histological categories of liver disease were statistically different in HIV-infected and HIV-uninfected patients. Multivariate analysis showed that age, alcohol abuse and serum antibodies to HIV were independently associated with severe CH or cirrhosis. Thus, HIV may enhance the risk of severe liver disease in drug users with hepatitis C, independently of the degree of immune dysfunction. Alcohol abuse may contribute independently, aggravating the cause of HCV-dependent liver disease.

Adult↗