Reversible effect of an inhalational anaesthetic on lymphocyte motility

Effect of halothane on intercellular adhesion molecule-1 (ICAM-1) in melanoma cells

There have only been a few reports relating to the effect of inhalational anesthetics on the tumor cell morphology in cancer patients undergoing surgery. We hypothesized that some anesthetic agents might influence the spread of unresectable cancer cells and might additionally worsen the condition of the patient due to depressed host immune surveillance. We therefore evaluated the influence of halothane on tumor cell adhesion, which is closely linked to tumor cell metastasis. Human melanoma cells from SK-MEL-37 cell-line were exposed to 4% halothane for 3, 6, 12 or 24 hours, respectively. Furthermore, after 24 hours halothane exposure, they were incubated in a 5% CO2 atmosphere for 12 or 24 hours. The cells were then analyzed using a fluorescence flowcytometer and intercellular adhesion molecule-1 (ICAM-1) expression in SK-MEL-37 cells was quantified as the intensity of fluorescence of ICAM-1 expressed in 10,000 cells. ICAM-1 expression in cells exposed to halothane for 3, 6, 12 or 24 hours was lower than that of non-exposed cells and returned to control level after further incubation in 5% CO2 atmosphere for either 12 or 24 hours. We conclude that halothane might affect the progression of tumor cell metastasis in vitro.

Volatile anesthetics block actin-based motility in dendritic spines

Dendritic spines form the postsynaptic contact sites for most excitatory synapses in the brain. Spines occur in a wide range of different shapes that can vary depending on an animal's experience or behavioral status. Recently we showed that spines on living neurons can change shape within seconds in a process that depends on actin polymerization. We have now found that this morphological plasticity is blocked by inhalational anesthetics at concentrations at which they are clinically effective. These volatile compounds also block actin-based motility in fibroblasts, indicating that their action is independent of neuron-specific components and thus identifying the actin cytoskeleton as a general cellular target of anesthetic action. These observations imply that inhibition of actin dynamics at brain synapses occurs during general anesthesia and that inhalational anesthetics are capable of influencing the morphological plasticity of excitatory synapses in the brain.

Effect of general anaesthesia and surgery on neutrophil function

The effects of general anaesthesia and surgical trauma on neutrophil function were studied in 60 female ASA 1 and 2 patients undergoing anaesthesia for gynaecological surgery. Patients were divided into three groups depending on the degree of trauma and duration of surgery. Group 1 (n = 15) were patients for dilatation and curettage (minor surgical trauma) and were given 2% halothane. Group 2 (n = 30) had laparoscopic surgery (moderate surgical trauma) and received either 0.5% halothane or 1% enflurane. Group 3 (n = 15) were those having hysterectomy (major surgical trauma) and received 0.5% halothane for a longer duration. Venous samples were taken 30 min before anaesthesia (control value), 10 min after induction of anaesthesia, 10 min after the start of surgery, 30 min after the end of anaesthesia and 24 h later. Phagocytic index, nitroblue tetrazolium reduction test, total leucocyte count, and differential leucocyte counts were performed on each sample. Data were analysed by paired t-test to compare findings in the same patient and by unpaired t-test for differences between groups. Anaesthesia with halothane 0.5% to 2% caused a dose-related depressant effect on leucocyte function which reversed. Enflurane 1% on the other hand caused significantly greater depression of leucocyte function compared with 0.5% halothane which persisted during the recovery period and recovered on the first postoperative day. Total leucocyte counts also showed a fivefold increase in the major surgery groups.

Immunologic parameters in patients with thyroid cancer

We evaluated various immunologic parameters in patients with papillary and follicular carcinomas of the thyroid gland. Our studies included examinations of peripheral blood lymphocytes and skin reactions to selected antigens. Preoperative peripheral blood tests were found to be normal except for an elevated percentage of IgG X Fc+ T-cells (T gamma). Skin reactions (phytohemagglutinin, purified protein derivative) were greater preoperatively than postoperatively. In postoperative cases without tumor recurrence, absolute numbers of T-cells and lymphocytes were reduced. OK-432 is a biologic response modifier of a streptococcal preparation and was used as immunotherapy in postoperative patients. This therapy seemed to augment the absolute numbers of T-cells and lymphocytes as well as purified protein derivative skin reactions in the patients without tumor recurrences. In the patients with postoperative tumor recurrences, there was an abnormal reduction in the percentage of T-cells and in the absolute numbers of T-cells and lymphocytes. OK-432 treatment was not significantly effective in normalizing this reduction.

Effect of lidocaine on the function of immunocompetent cells. II. Chronic in vivo exposure and its effects on mouse lymphocyte activation and expression of immunity

In vivo exposure of mice to lidocaine (0.25 mg/10 g body weight 4 times a day for 7 days) resulted in impairment of immunocompetent cell function. Spleen lymphocytes removed from animals immediately and 3 days after lidocaine exposure showed changes in their surface charge properties, inhibition of blastogenesis in response to concanavalin A and lipopolysaccharide, and inhibition of antigen-stimulated activation as measured by the mixed lymphocyte reaction. Lymphocytes from animals sensitized to keyhole limpet hemocyanin showed a significantly lower capacity to produce macrophage migration inhibitory factor 8 days after termination of exposure to lidocaine. Animals exposed to the drug were unable to accumulate an adequate number of immunocompetent cells at the site of challenge with a foreign substance (i.e. dextran), and the ability of the animals to destroy tumor cells nonspecifically and specifically was also impaired. The results indicated that chronic exposure to lidocaine resulted in impairment of lymphocyte function, even in the subsequent absence of the drug, and in significant changes in the expression of the immune response.

The effects of three differing anaesthetics on the immune response

A clinical study was undertaken to investigate changes in the immune response in patients undergoing three differing anaesthetic techniques for inguinal hernia repair. No significant differences between anaesthetic groups were demonstrated in the haematological parameters. The value of mitogen stimulation tests was questioned in the clinical setting. The migratory component of neutrophil function was shown to be preserved following conduction anaesthesia compared to the other anaesthetic groups and its possible advantage noted.

Observations on immunologic parameters in laryngeal cancer patients

Patients with laryngeal cancer were examined immunologically before treatment and for 1-10 years after treatment. In the pretreatment group, the percentage of T cells, lymphocyte blastoid reaction (PHA, concanavalin A), and skin reactions (PHA) were generally in the normal range, but absolute numbers of T cells and lymphocytes were reduced in most patients. In the group with no recurrence after surgery, the absolute number of T cells and lymphocytes, IgG X FcR+T cells (T gamma), and skin reactions was normal in many cases. The group with recurrence showed reduced percentage of T cells and an absolute number of T cells and lymphocytes. The absolute number of T cells and lymphocytes and the PPD skin reaction increased after surgery in some cases, but reductions in some of the parameters were noted in a few cases long after surgery. Radiation therapy for patients with tumors at early stages did not significantly change the percentage of T cells or the skin reactions.

Cell-mediated immune suppression due to alfathesin in short-term anaesthesia

The immunosuppressive effects on cell-mediated immunity of alfathesin, when used as the sole agent for short-term anaesthesia, were investigated in ten women undergoing pregnancy termination. Cell-mediated immunity was evaluated by E rosette formation in peripheral blood (reflecting the percentage of T lymphocytes) and by proliferative responses to the mitogens concanavalin A and phyto-haemagglutinin in various concentrations. Measurements were made before alfathesin was administered, and again after 60 minutes, two days and seven days. Significant reductions in the percentage of E rosettes in peripheral blood and in mitogenic responses to concanavalin A were observed 60 minutes after administration of alfathesin. A model is proposed in which alfathesin binds to lymphocytic membrane receptors, thus affecting in vitro cell-mediated immune reactions.

Anesthetic drugs accelerate the progression of postoperative metastases of mouse tumors

Experiments were made to investigate the effect of four anesthetic drugs that are commonly used in surgical practice on the postoperative growth of mouse tumors in syngeneic recipients. These experiments revealed that some of the anesthetics when applied for surgical excision of the local tumor, strongly accelerated postoperative progression of spontaneous lung metastases produced by the 3LL Lewis lung carcinoma and by the B16 melanoma. Some of the drugs caused the appearance of metastases in organs, such as the liver, in which spontaneous metastases are not usually produced by these tumors. A T10 sarcoma clone that does not produce detectable metastases in immune intact mice even following intravenous injection, did produce metastases when injected into animals treated with pentothal sodium.

Influence of anaesthesia and surgery on neutrophil chemotaxis

Chemotactic migration of leucocytes is one of the earliest and essential events among the host defense mechanisms against infection. Therefore, the influence of anaesthesia and surgery on leucocyte chemotaxis was investigated in patients requiring elective surgery. The chemotactic migration of peripheral blood leucocytes was measured by a modification of Boyden's method immediately before and after operation and on the second and third postoperative days. In addition, the influence of exposure to different molar concentrations of thiopentone on chemotactic migration was investigated in vitro. A statistically significant inhibition of leucocyte chemotactic migration was observed in the immediate postoperative period. (P less than 0.05). However, this inhibition was of short duration and chemotactic activity returned to normal on the day after operation under general anaesthesia. Exposure to thiopentone produced a significant and dose dependent inhibition of chemotactic migration in vitro. It is concluded that surgery under general anaesthesia and exposure to thiopentone in vitro produce a significant though reversible inhibition of chemotactic migration of leucocytes.

Effects of oxygen on pulmonary macrophages and alveolar epithelial type II cells in culture

Cultures of Chinese hamster lung fibroblasts and explants of 20-day-old rat lungs were exposed to 95% oxygen with 5% CO2 in vitro. The Chinese hamster cells had stopped dividing after 17 hours exposure and cell death occurred at a mean time of 67 hours (s.d. 15 hours). The rat lung explants showed macrophages moving over a monolayer of alveolar type II epithelial cells. Both cell types appeared to function normally for 24 hours but cell division in the type II cells was about 50% of control between 12 and 24 hours of exposure and virtually ceased after 26 hours. Cell death commenced after 4 days and was complete in 9 days. Macrophages divided freely in the control cultures but only one division was seen during exposure to oxygen and that occurred during the first 24 hours. Motility was reduced by 50% during the second day of exposure and stopped during the 3rd day. No live macrophages were seen after 4 days exposure. These culture systems appear very suitable for screening drugs for their protective effect against oxygen toxicity.

Effect of halothane anaesthesia on primary antibody response in the chicken

The effect of a single anaesthesia of 2 hours' duration with 1% v/v halothane and of 1, 2, and 3 hours' duration with 2% v/v halothane was studied on the primary antibody response in line-bred chickens. In contradistinction to earlier studies, the immunisation was performed during anaesthesia to resemble antigenic exposure in surgical practice. The IgG and IgM antibodies against the antigens, bovine serum albumin (BSA) and formalin-killed Brucella abortus organisms (Brucella), were quantified by the enzyme-linked immunosorbent assay (ELISA). The halothane concentration of the blood was measured by gas chromatography at the end of anaesthesia. Anaesthesia with 1% and 2% v/v halothane given in the antigen-processing phase of humoral immune response had no effect on the concentrations of IgG-and IgM-anti-BSA and IgG-and IgM-anti-Brucella antibodies in the primary antibody response.

Leucocyte-migration-inhibition test in patients with colorectal cancer: clinicopathological correlations

Leucocyte-migration-inhibition test was used to study the immune reactions of leucocytes from 136 colorectal cancer patients, 43 patients with non-cancerous chronic colorectal diseases and 82 controls, with saline extracts of HT29 line. A positive inhibition was found in only 43% of colorectal cancer patients. It was higher in carcinomas of limited extension than in invasive ones (64% against 39%). Furthermore, operation by itself had a depressive effect on the reaction, as the positivity in 25 patients tested twice was 64% before operation and 32% after. Leucocytes from patients with non-cancerous chronic colorectal diseases gave many positive reactions (65%). The percentage of positivity was about the same for diseases with high, low or no risk of cancerization. Hence the antigen(s) of tumour extracts that react with patient's leucocytes are, at least partially, unrelated to cancer.

Effect of surgery on tumour-directed leucocyte responses

Leucocytes from 22 out of 26 patients with mammary carcinoma were significantly cytotoxic in vitro for cells cultured from mammary tumours though only two out of 17 of these preparations were cytotoxic for cells cultured from tumours arising at other sites. In the immediate postoperative period reactivity of patients' leucocytes with mammary tumour cells was undetectable but returned within one week of surgery. Leucocyte cytotoxicity may therefore offer a model in which the mechanism of postoperative depression of immunological competence may be investigated.

The effects of halothane on cultured mouse neuroblastoma cells. I. Inhibition of morphological differentiation

Mouse neuroblastoma cells (clone NB2a) were cultured in the presence of 0.3-2.1% halothane in the gas phase for up to 72 h. Halothane inhibited neurite extension dose dependently and virtually abolished microspike formation even at the lowest concentration tested. These effects were completely reversible. Electron microscopy demonstrated that microfilaments measuring 40-80 A in diameter are the only fibrous organelles visible within microspikes. When the cells were exposed to halothane, no microfilamentous complexes could be identified in any cells and the subcortical regions of neurites often appeared devoid of individual microfilaments. Microtubules were still present in neurites after exposure to halothane concentrations at which microfilaments disappeared. However, at concentrations above 1.0%, microtubules gradually appeared to decrease in number. Short-term experiments showed that existing neurites and microspikes rapidly retracted when suddenly exposed to culture medium equilibrated with 1.0% halothane and quickly reformed when the halothane was removed. The inhibition of neuroblastoma cell differentiation by halothane appears to be mediated by disruption of 40-80 A diameter microfilaments.