K. James

BCG immunotherapy of bladder cancer: 20 years on

1The situation is similar for most industrialised western nations, with incidence rates of 18 to 30 new cases per 10 0 000 men placing bladder cancer among the top five cancers in this sex. It is unclear why women are affected a third to a quarter less often than men. In 75% of patients the disease is diagnosed in its early superficial stage, usually as a result of gross or microscopic blood in the urine. However, with an overall 65% recurrence rate and 30% progression rate, even these patients need lifelong medical vigilance involving periodic internal inspections of their bladders. The cause of bladder cancer is unknown, but the disease has been strongly associated with exposure to certain aromatic chemicals, notably aniline dyes and benzidine compounds. Cigarette smoking with its release of -naphthalene and -napthalene into the urine is estimated to cause over one half of bladder cancers found in men and one third of those found in women. 2 Over 90% of bladder cancers found in such settings are of the transitional cell type, with squamous cell carcinoma usually occuring in patients with chronic infections such as bilhariasis. Among the transitional cell carcinomas, depth of penetration (stage) and degree of cellular anaplasia (grade) are the most important factors for prognosis. One particular mucosal high-grade lesion called carcinoma-in-situ is not surgically accessible because of its diffuse surface-spreading behaviour. Untreated carcinoma-in-situ will progress to muscleinvasive disease in about 80% of cases within 5 years. 3

Human monoclonal antibody production: Current status and future prospects

Since the first description of monoclonal antibody secreting cell lines by KtShler and Milstein in 1975, rodent monoclonal antibody technology has been rapidly and successfully applied to a wide variety of biological problems of both theoretical and practical importance. In the health care field for example, this has resulted both in the development of new and improved diagnostic and therapeutic procedures and an increase in our understanding of human biology. Unfortunately progress in the human monoclonal antibody field has been far less spectacular. Although immortalised human cell lines secreting specific antibody were described as long ago as 1977 and their potential immediately recognised (Steinitz et al., 1977) the development of human monoclonal antibody technology has been a slow, laborious and often unrewarding exercise (see later). Nevertheless in spite of the many problems encountered to date work has continued unabated, sustained by the widely held belief that this technology would result in improved diagnostics and therapeutics and would

Interactions between cytokines and α2-macroglobulin

Abstract Cytokines are often thought of as short range, short half-life molecules. This view may now be challenged by recent findings that indicate that α 2 -macroglobulin and antibodies to cytokines may alter cytokine kinetics in vivo. α 2 -Macroglobulin, one of the major proteins in serum, can bind a wide range of physiologically important molecules. As Keith James reviews, the interaction between α 2 -macroglobulin and a number of cytokines has recently come under scrutiny, revealing a new and potentially important mechanism for the modulation of cytokine activity, while in the following paper a modulatory role for anti-cytokine antibodies is considered.

Immunosuppression by seminal plasma and its possible clinical significance

Several components of semen have immunomodulatory effects; these include spermatozoa(1-3) and a variety of seminal plasma factors. In addition semen may contain a small number of immunocompetent cells(4). In this review Keith James and Timothy Hargreave discuss the immunological effects of human seminal plasma, including its suppressive effect on in vitro and in vivo immune responses, the nature and action of the factors involved and their possible clinical relevance.

Changes in urinary cytokines and soluble intercellular adhesion molecule-1 (ICAM-1) in bladder cancer patients after bacillus Calmette-Guérin (BCG) immunotherapy.

Intravesical immunotherapy for carcinoma in situ of the bladder is arguably the most effective form of tumour immunotherapy described to date. Following repeated instillations of BCG organisms into the bladder, large quantities of cytokines are detected in patients’ urine. This study concerns the production of IL‐1β, IL‐2, IL‐4, IL‐6, IL‐8, IL‐10, tumour necrosis factor‐alpha (TNF‐α), interferon‐gamma (IFN‐γ) and soluble ICAM‐1 (sICAM‐1) throughout the six weekly instillations which comprise a therapeutic course. Sequential instillations of BCG induced secretion of IL‐1β, IL‐2, IL‐6, IL‐8, IL‐10, TNF‐α, IFN‐γ and sICAM‐1 into urine. The responses were heterogeneous between patients and cytokines, but some general trends were evident. Although cytokine levels were initially low, their concentration increased with repeated instillation of BCG. Certain cytokines (e.g. IL‐6, IL‐8 and IL‐10) could be detected after the first instillation, whilst others (e.g. IL‐2 and IFN‐γ) were not detected until after the third or fourth instillation. Interestingly, IL‐4 was not detected, perhaps suggesting a differential effect on Th2‐like responses. Some patients produced particularly elevated or non‐detectable levels of cytokines, and a positive correlation was found between the production of various cytokines. The production of a particular cytokine did not correspond with lack of production of another species. Whether monitoring the production of cytokines following therapy may be of prognostic value will be determined in a larger series of patients. However, as these potent immunomodulators are thought t o be important for the 75% complete clinical response observed with BCG therapy, there remains the possibility that detection of the products of an activated immune system may correlate with eventual clinical outcome. This study is a necessary forerunner to full prognostic evaluation of such immunological data.

Extracellular organelles (prostasomes) are immunosuppressive components of human semen.

Numerous reports have ascribed immunosuppressive activity to human seminal plasma and there is growing agreement that much of this activity can be accounted for by the very high levels of E series prostaglandins present (up to 300 μm 19‐hydroxy prostaglandin E). However not all suppressive activity is due to prostaglandin since several reports have appeared of high molecular weight active substances and we have found that stripped seminal plasma is still effective in inhibiting the mitogen‐induced proliferation of lymphocytes. In this study such immunosuppressive activity has been separated by molecular size fractionation and the activity has been found to be particulate and corresponded to the previously reported prostasomes. These are trilaminar to multilaminar vesicles (150 nm diameter) which are secreted by the prostate. Pure preparations of prostasomes inhibited mitogen‐induced lymphoproliferation in a dose‐dependent manner with a concentration of prostasomes equivalent to 40% of that seen in seminal fluid giving 69% suppression of thymidine incorporation. The suppressive activity survived boiling and therefore was unlikely to be due to enzymatic action associated with these organdies. Interaction with the accessory cells, involved in full development of the lymphoproliferation induced by mitogen, was indicated and this possibility was supported by the demonstration of a direct effect of prostasomes on macrophage function using a mouse macrophage cell line. The prostasomes in semen may play a complementary role to the prostaglandins in neutralizing the immune defences of the female reproductive tract. This combination would allow the alloantigenic spermatozoa the best chance of achieving fertilization, but at the same time leave the recipient open to any infection present in the semen.

Immunosuppression by human seminal plasma-extracellular organelles (prostasomes) modulate activity of phagocytic cells

PROBLEM: Prostasomes are trilamellar to multilamellar vesicles produced by the acinar cells of the human prostate and are present in appreciable amounts in normal human semen. The aim of this work was to study the effect of prostasomes on human polymorphonuclear cell and monocyte function.

Radio-Immunoassay Detection of Interferon-Gamma in Urine after Intravesical Evans BCG Therapy

Our previous studies suggested that interferon-gamma (IFN gamma) was produced in the local immune response to intravesical BCG. To confirm this we modified a commercially available radio-immunoassay for detection of this lymphokine in urine. The urinary levels of IFN gamma were compared in serial urine samples taken from six patients undergoing treatment with Evans strain BCG and seven patients receiving intravesical mitomycin C/epirubicin. IFN gamma was detected consistently in response to BCG with levels reaching a peak (mean 67.1 U/ml., range 7.9 to 155.9 U/ml.) four to six hours post-instillation whereas after other intravesical agents no IFN gamma was detectable after seven of 13 instillations. After the remaining six instillations lower levels were detected (mean 7.4 U/ml., range 0.6 to 22.4 U/ml.). The difference in peak levels between the two groups was statistically significant (p less than 0.001 Mann Whitney U test). These results are further evidence of specific cellular immune activity in response to intravesical BCG therapy and suggest anti-tumour mechanisms similar to allograft rejection and autoimmunity.

Immunocompetent cells in human testis in health and disease

The authors have investigated lymphocyte subpopulations and macrophages in normal human testes and the testes of patients under investigation and treatment for subfertility. Specific monoclonal antibodies were used in an indirect immunoperoxidase technique. In normal tissues, T lymphocytes (Leu 4-positive cells) were present in the rete testis with a preponderance of cells of the suppressor/cytotoxic phenotype. In contrast, no lymphocytes were detected within the peripheral portions of the testis. Cells reacting with the anti-Leu M3 monoclonal antibody, which defines monocytes/macrophages, were detected in appreciable numbers in peripheral testis with a specific location around the seminiferous tubules. HLA-DR-positive cells (human leukocyte antigens--class II [DR] determinants of the major histocompatibility complex) also were identified and showed a similar pattern of distribution to that of the Leu-M3 positive cells. While no lymphocytes were seen in the normal peripheral testis, T lymphocytes were detected in testicular biopsies from subfertile patients. Suppressor/cytotoxic T cells (Leu 2a-positive) predominated in patients with oligozoospermia and obstructive azoospermia while T cells of the helper/inducer phenotype predominated in patients with unilateral testicular obstruction and in postvasectomy patients. Sperm antibody measurements correlated with these findings.

The influence of age and gender on serum dehydroepiandrosterone sulphate (DHEA-S), IL-6, IL-6 soluble receptor (IL-6 sR) and transforming growth factor beta 1 (TGF-β1) levels in normal healthy blood donors

Dysregulation of IL‐6 synthesis is thought to play a role in the development of a number of age‐related conditions, such as rheumatoid arthritis, osteoporosis, atherosclerosis, Alzheimers disease and B cell malignancies. Recently it has been suggested that the production of IL‐6 is influenced by the adrenal hormone dehydroepiandrosterone (DHEA) and its sulphated derivative DHEA‐S. In humans we investigated the relationship between DHEA‐S, IL‐6, IL‐6 sR and TGF‐β1 in the serum of normal healthy male and female blood donors. Using immunoassay techniques we found that the serum levels of DHEA‐S significantly (P = 0.0001) decreased with age in both males and females. Furthermore, mean DHEA‐S levels in all age groups were significantly (P = 0.0001) higher in males. Such correlations were not apparent for IL‐6 using a standard assay, but a high sensitivity assay revealed that serum IL‐6 was significantly (P = 0.0018) positively correlated with age in males only. In addition, serum levels of DHEA‐S were significantly (P = 0.048) negatively correlated with serum IL‐6, again in male subjects only. In contrast, serum IL‐6 sR and TGF‐β1 levels were not correlated with age in either males or females and were not significantly different between the sexes. However, a significant (P = 0.024) negative correlation between DHEA‐S and IL‐6 sR was found in males. These studies clearly highlight the complex nature of the relationship between these molecules in the ageing process in normal healthy blood donors and demonstrate the need to use high sensitivity assays when measuring IL‐6 in apparently healthy individuals under the age of 70 years.