Objective: To assess whether statin administration for HIV-associated hyperlipidemia has long-term effects on immune recovery (as expressed by the trend of mean CD4+ lymphocyte count), in patients on a virologically-active HAART regimen since 12 months or more.Methods: Single-centre, open-label, prospective study of 301 hyperlipidemic patients treated with statins (99 cases, with a predominant hypercholesterolemia), fibrates (116 subjects, when hypertriglyceridemia prevailed), or a isolated dietary/exercise program (86 patients, used as a control group). Neither epidemiological nor clinical, virological, or immunological differences were detected among the three study groups at baseline. During the subsequent follow-up, patients were excluded from evaluation should virological efficacy was not maintained, and/or initial hypolipidemic therapy was modified or interrupted for any reason.Results: The quarterly assessment of mean CD4+ lymphocyte count did not disclose any statistically significant difference among the three study groups, since baseline and until at least 24 consecutive months of follow-up. Our data tend to exclude relevant in vivo negative activities of statins on immune system recovery of HIV-infected individuals who undergo a virologically effective HAART treatment.Conclusions: Multiple, pleiotropic features have been attributed to both statins and fibrates, and also apparently significant effects on laboratory markers of HIV disease progression have been recently claimed or expected. Despite some preliminary in vitro and ex-vivo models, both the main hypolipidemic classes administered for the management of HIV-related dyslipidemia (both statins and fibrates) do not seem to act significantly on clinical immune response of patients successfully treated with HAART. Multifactorial pathways are expected to interact with the cell-mediated immune system of HIV-infected patients undergoing successful HAART, and further studies are needed to elucidate whether more subtle immune effects might be prompted by a long-term administration of hypolipidemic drugs in this speciasl setting.
The expression of the genes coding TNFalpha and TNF RII receptors (TNF RII: TNFR2 membrane and soluble domain, TNFR2/R7 soluble domain) was analysed in colon cancer at the II and III stage of disease, by estimation of mRNA expression. The study included 80 patients with histopathologically confirmed adenocarcinoma. The number of TNFalpha mRNA, TNFR2 mRNA and TNFR2/R7 mRNA copies were estimated in tumour and healthy tissue. The highest number of mRNA TNF-alpha copies were investigated in all samples of tissue and independently of the stage of disease. Simultaneously, we noticed the largest number of mRNA copies for TNFalpha and TNF R2/R7 in healthy cells at stage III of the disease. It is possible to draw a hypothetical line separating the anti-cancer activity of TNFalpha and its influence on cancer progression.
Regulated on activation, normal T-cell expressed and presumably secreted (RANTES), which generally mediates monocyte-macrophage (MO) activation and recruitment, is a protein of 8-10 kD that chemoattracts eosinophils, monocytes and certain T leukocyte subsets. RANTES is coded for by a gene cluster located on human chromosome 17 and is a human T-cell specific molecule. RANTES is a member of a beta intercrine subfamily reported to be a selective chemoattractant for human monocytes rather than neutrophils, and is also a chemoattractant for memory T lymphocytes, CD4+ cells. RANTES is a modulator of many important macrophage functions in addition to aggregation, such as chemotaxis and phagocytosis. Our investigations focussed on the ability to modulate the aggregation of macrophages induced by calcium ionophore A23187. The ionophore A23187 directly induced potent aggregation of MO which was markedly enhanced when the cells were pretreated with RANTES. However, the addition of RANTES in the absence of other co-stimuli did not directly induce aggregation. Additional cytokines examined for possible induction of macrophage aggregation were interleukin-1 (IL-1), tumor necrosis alpha (TNF-alpha), and IL-6; all proved to be incapable of inducing aggregation directly, nor did they enhance the effects of A23187 on macrophage aggregation. Additionally, we found that RANTES can directly stimulate MO to activate specific pathways of arachidonic acid cascade, inducing a synthesis and release of thromboxane (TxA2) and leukotriene B4 (LTB4). RANTES did not augment the potent ability of A23187 to induce increased production of LTB4 or TxA2 by human MO. These data suggest that RANTES can contribute directly to monocyte-leukocyte-activation during inflammatory responses, resulting in greater cell aggregation, activation, and specific pro-inflammatory arachidonic acid products release, such as TxA2 and LTB4.
The model of monozygotic twins has been repeatedly studied to control the genetic and age-specific effects on HIV disease. Focusing on this natural model, the expression of CD27/CD45RA differentiation markers and the distribution of the Vbeta TCR repertoire was analyzed on CD4+ and CD8+ T cells. In our HIV-discordant monozygotic twins, a significant reduction of naive T cells and a parallel accumulation of effector/memory T cells was induced by HIV infection, as well as a skewing of T cell repertoire evidenced by VbetaTCR analysis. The block of HIV replication by highly active antiretroviral therapy (HAART) restored most of the T cell maturation and selection process, with some exception among CTL differentiation and repertoire. Altogether, the model of HIV-discordant monozygotic twins is a valuable tool showing that HAART is not able to completely restore the CTL profile.
The recent advances in the investigation of tumor immunobiology have suggested that cancer chemotherapy, in addition to its well known cytotoxic activity, may play modulatory effects on the endogenous production of cytokines involved in the control of both tumor angiogenesis and antitumor immunity. Cancer chemotherapy constantly acts with inhibitory effects on anti-bacterial, anti-viral and anti- mycotic immune responses, whereas its action on anticancer immunity, which is mainly mediated by lymphocytes, has still to be better investigated and defined. The present study was carried out to evaluate the influence of chemotherapy on lymphocyte count and its relation to the clinical response in cancer patients suffering from the most commonly frequent tumor histotypes, including lung, colorectal, breast and prostate carcinomas. The study included 144 consecutive metastatic solid tumor patients. Lung cancer patients were treated with cisplatin plus gemcitabine, colorectal cancer patients received oxaliplatin plus 5-fluorouracil, while those affected by breast cancer or prostate carcinoma were treated with taxotere alone. An objective tumor regression was achieved in 66 out of 144 (46 percent) patients, whereas the remaining 78 patients had only a stable disease (SD)or a progressive disease. Independently of tumor histotype and chemotherapeutic regimen, a lymphocytosis occurred in patients who achieved an objective tumor regression in response to chemotherapy, and lymphocyte mean count observed at the end of the chemotherapeutic treatment was significantly higher with respect to the values seen before the onset of treatment. On the contrary, lymphocyte mean number decreased on chemotherapy in patients with SD or PD, even though the decline was statistically significant with respect to the pretreatment values in the only patients who had a PD in response to chemotherapy. This study would suggest that chemotherapy itself may paradoxically act, at least in part, as a cancer immunotherapy by inducing lymphocytosis, as well as previously demonstrated for the only immunotherapy with IL-2, probably by modulating the cytokine network and correcting the altered endogenous production of cytokines, responsible for cancer-related immunodeficiency.
Immunophenotype of mobilized stem blood cells (CD34+) was studied in 29 patients with late post-traumatic spinal lesions. The CD34+ cells demonstrated different levels of expression of CD45, CD38, monomorphic determinants HLA-DR and gp130 epitopes. Most patients presented with a CD34+ cell fraction with no or low expression of common leukocytic antigen CD45. Only 2 patients had greater than 15 percent of HLA-DR-CD38- cells in the CD34+ fraction. A common transducer molecule of interleukin-6 family cytokines gp130 was expressed on stem (CD34+) cells in all the cases, 26 percent of the patients had an activated gp130 phenotype, i.e. a combination of C7+ and A1- epitopes.
Interleukins IL-1beta, IL-6 and TNF are increased in plasma of patients with severe infections and septic shock. Our objective was the evaluation of IL-1beta, IL-6 and TNF in plasma and exudates of pleural fluid and their contribution to the diagnosis. We studied 44 patients, 27 men and 17 women with mean age 66.81 +/- 11.75 years; 16 with pneumonia and parapneumonic effusion, 14 with primary lung cancer and pleural effusion and 14 with tuberculous pleuritis. We measured IL-1beta, IL-6 and TNF in serum and pleural fluid with ELISA. In patients with pneumonia and parapneumonic effusion the mean value of IL-1beta IL-6 and TNF in plasma was 9.05, 19.24 and 21.34 pg/ml and in pleural fluid 10.34, 32.19 and 25.30 pg/ml. In patients with lung cancer the mean values of IL-1beta, IL-6 and TNF were 5.33, 11.74 and 11.51 pg/ml and 6.70, 13.13, 20.89 pg/ml, respectively. In those with tuberculous pleuritis the respective mean values were 10.33, 49.94, 21.27 pg/ml and 14, 56.59, 23.58 pg/ml. In conclusion, IL-1beta and IL-6 were found increased in plasma and tuberculous pleural fluid, indicating an inflammatory status.