Search

Objective: To analyze longitudinally the basal natural killer cell activity in patients with invasive cervical carcinoma, the natural cytotoxicity was related to the most important known prognostic factors, and evaluated with respect to the clinical outcome of cervical disease., Materials and Methods: Forty-six patients with histologically proven invasive cervical carcinoma treated and followed at the Institute of Gynecology and Obstetrics, Ancona University, Salesi Hospital, were consecutively recruited from 1989 to 1992 and included into the study. For immunologic investigation, natural killer cell activity and peripheral blood T-lymphocyte subsets were tested before primary treatment and during the follow-up period, every 6 months. Natural killer activity was determined by target cell retention of the fluorescent dye carboxyfluorescein diacetate; the K 562 cell line was used as target cells., Results: A significant inverse relationship was observed between natural killer activity and disease stage (p = 0.001); patients with stage IV disease had the lowest level of natural cytotoxicity. The reduction of natural cytotoxicity was not accompanied by any alteration of lymphocyte distribution. The longitudinal analysis showed an increase of natural killer activity after surgical removal of the tumor, persisting during the follow-up, but all the 9 patients who recurred showed, at the time of disease recurrence, a significant decrease of their natural cytotoxic potential., Conclusion: Natural killer cell activity seems to be a functional index of immune status, significantly related to the stage and the clinical outcome of disease.

A good body of experimental and clinical results has supported the existence of numerous reciprocal interactions among the nervous, endocrine and immune systems. Increasing evidence has been accumulated in the last years on the interaction between pituitary-thyroid hormones and the immune system on the basis of either the existence of receptors for thyreotropic and thyroid hormones on lymphocytes or the frequent immune alteration in physiological and pathological fluctuations of thyroid hormones. The data were obtained either in animals with experimentally induced hyper- or hypothyroidism or in humans with various hyperthyroid or hypothyroid situations. Conversely, immune-derived products such as lymphokines and monokines have been shown able to influence the pituitary-thyroid axis modulating either the thyroid hormone levels or the hormone/cytokine production by thyrocytes. The present paper aims at summarizing the data available on the existence of thyroid-immune interactions, and at analyzing the possible integration between pituitary-thyroid hormones and immune factors in favoring the development and maintenance of both thymic and peripheral immune efficiency. The relevance of pituitary-thyroid-immune interactions is discussed for its implication in the ageing process.

The objective was to examine the prevalence of human papillomavirus (HPV) DNA infection in mild cervical dysplasia and to evaluate longitudinally the persistence of HPV DNA positivity in an observational study, aiming at identifying the role of peripheral blood lymphocyte natural killer activity in the natural history of dysplastic disease. Twenty-three patients with histologically proven mild cervical dysplasia were selected. The HPV DNA positivity, determined by polymerase chain reaction, and cervical dysplasia were monitored cytologically and colposcopically at the 3rd (time 1), 6th (time 2) and 12th months (time 3), and defined by biopsies for routine histology taken at times 2 and 3. For each patient included in the study, the immune reactivity was evaluated at the time of diagnosis and afterwards, longitudinally during the follow-up. The immune status analysis included T lymphocyte subsets (CD3, CD4, CD8, CD56, CD16 monoclonal antibodies by Beckton Dickinson, Mountain View, Calif., USA) and determinations of natural killer cell activity (against the sensitive cell line K 562). Eighteen out of the 23 women with mild cervical dysplasia (78.3%) were found positive for HPV DNA, with a significantly high representation of HPV DNA type 16 (55.6% of cases). At the end of the study, 12 out of 18 HPV-DNA-positive women became negative (defined by two or more negative tests) for the original HPV DNA type, with 66.7% of spontaneous HPV DNA negativization rate (p = 0.6).(ABSTRACT TRUNCATED AT 250 WORDS)

The objective was to evaluate natural cytotoxicity of peripheral blood during interferon treatment in cervical intraepithelial neoplasia grade 2 (CIN2), as index of interferon activity. Twenty-one patients with CIN2, histologically proven, were treated with interferon alpha 2b (Intron A, Sheering-Plough Corp.), in a dose of 3,000,000 units three times per week for 8 weeks self-administered by intramuscular injection. The rate of remission to the interferon treatment was 38.1%. Eight healthy patients had a significant increase in natural killer activity during and after the treatment (p < 0.001), whereas the 13 nonresponder patients remained with low values of natural killer activity. By analyzing the basal natural killer activity before the treatment, the patients with clinicopathologic remission had a significantly higher mean value than nonresponder patients (p = 0.007). Notwithstanding the specimen exiguity, the individual basal natural killer activity seems to be a predictive parameter of interferon treatment response in patients with CIN2.

A longitudinal evaluation of the natural killer (NK) cell activity of peripheral blood lymphocytes was performed in 17 patients with advanced ovarian cancer (treated surgically and with subsequent multiagent chemotherapy) for a median follow-up period of 32 months. At the time of primary treatment, the mean value of NK cell activity was significantly lower in patients who then had disease progression (p < 0.05) than in patients with progression-free survival. During the follow-up period, no significant modifications of the NK cell activity were observed; only at the time of clinical disease progression did the NK cell activity show a significant reduction. We conclude that the NK cell activity is a potentially important prognostic factor.

We have studied the systemic T-lymphocyte subset and, in particular, the natural-killer (NK) activity in 23 patients with cervical intra-epithelial neoplasia (CIN), and 11 controls (a history of normal cervical PAP smears and colposcopy patterns). The lymphocyte phenotypes were studied using a panel of monoclonal antibodies, and NK activity was evaluated as the percentage lysis of K 562 target cells. In patients with CIN we found a significant decrease in NK activity (p = 0.002) which was directly correlated with the grade of CIN, with no alterations in the absolute number of NK cells.

Basal natural killer (NK) cell activity in peripheral blood lymphocytes (PBLs) of 29 patients with gynecologic malignancy and 10 healthy controls was performed using K 562 cell line. A significant decrease of NK cell activity was observed in patients with gynecologic malignancy (p = 0.003). The NK cell activity of patients with poorly differentiated tumor or with stage IV of disease was significantly reduced with respect to patients at any other lower grade or earlier stage. We conclude that in patients with gynecologic malignancies there is a decrease of basal NK cell activity of PBLs, which is more significant in cases of distant tumor dissemination or poorly differentiated tumor (p less than 0.001).

The age-dependent changes in thyroid-hormone blood levels and the effects of in vivo and in vitro thyroid-hormone administration on both basal and lymphokine-induced spleen cell natural killer (NK) activities have been investigated in young and old Balb/c mice. Both thyroxine (T4) and triiodothyronine (T3) plasma levels decline progressively with increasing age of the mice, displaying in 25-month-old mice only 50 and 60% of the T4 and T3 blood levels, respectively, found in young mice. In vivo T4 administration to old mice causes a significant increment in endogenous NK activity (2.2-fold increase), which approaches the values observed in young animals, while it does not modify NK activity in young mice. The T4 injection in old mice does not induce changes in the lymphocyte sub-populations. When T4 is administered in vitro alone or in combination with interferon (IFN) and/or interleukin 2 (IL-2), no effect is observed either on basal activity or IL-2-induced cytotoxicity, whereas the IFN sensitivity of spleen cells from old mice is significantly recovered (4-fold increase). T4 is able to increase IFN-induced cytotoxicity even when administered in vitro simultaneously with IFN to the cytotoxic assay (1.5- and 2.7-fold increases in young and old mice, respectively). Under these conditions, IFN alone is not able to exert any boosting effect even at a young age. In vivo propylthiouracil (PTU) administration completely abrogates the IFN responsiveness of spleen cells in young mice. The interruption of the PTU treatment results in a recovery of IFN-inducible NK cytotoxicity. Taken together, our findings point out the important role of thyroid hormones in the modulation of NK cell activity and provide a new insight into the mechanisms by which the endocrine system is able to influence the expression of natural immunity.

The thymus produces humoral factors that induce the proliferation and differentiation of T cells which are responsible for cell-mediated immunity. Experimental data have suggested that this thymic hormone production is modulated by the neuroendocrine network and, in particular, by growth hormone (GH) and thyroid hormones. To study the role played by GH in thymic endocrine activity in humans, the circulating level of one of the best known thymic peptides, i.e. thymulin (Zn-FTS), has been determined, after a washout period of 2 weeks without GH treatment, in GH-deficient children before and after a single injection of GH. The basal thymulin level is consistently lower in GH-deficient children than in healthy age-matched controls. A single injection of GH induces a significant increment of the thymulin level for at least 48 h. Since thymulin activity may also depend on zinc bioavailability, on thyroid hormone turnover and on the eventual presence of thymulin-inhibitory substances, all these aspects have been checked. No supporting evidence regarding the existence of these kinds of interferences in GH-deficient children has been substantiated. A positive correlation has been found between the serum level of insulin-like growth factor I, but not of GH, and thymulin activity. These data suggest that GH may directly or indirectly modulate the thymic endocrine function in humans. Whether and to what extent such a modulation is relevant to the functioning of the immune system remains to be ascertained.

A good body of experimental and clinical evidences suggests that bidirectional interactions do exist between the neuroendocrine system and the thymus activity. In particular, thymic endocrine activity seems to be strongly influenced by neuroendocrine signals. In this context, studies performed in hyper- and hypothyroid subjects and in the low triiodothyronine (T3) syndrome, which affects premature infants, have clearly shown that thyroid hormones and in particular T3 physiologically modulate thymic peptide secretion. In vitro experiments, with thymic whole-organ cultures, have demonstrated that thyroid hormones exert their action on the epithelial cells of the thymus deputed to synthesize and secrete thymic peptides and that such an effect does not seem to depend on the known permissive action of thyroid hormones.