Kallikrein and kinin receptor expression in inflammation and cancer.

The kallikrein family of serine proteases has been investigated in many inflammatory disorders as molecular mapping, gene characterisation and cloning of kinin receptor genes have unfolded experimentally. In the molecular events of the inflammatory response the kallikrein cascade plays a significant role, since it is considered to initiate and maintain systemic inflammatory responses and immune-modulated disorders. A primary event is the chemotactic attraction of neutrophils which deliver the kallikrein-kinin cascade to sites of cellular injury and carcinogenic transformation of cells. The present study establishes the casual involvement of the kallikrein cascade in infection, inflammatory joint disease, acute transplant rejection, renal glomerular diseases, angiogenesis and carcinoma. We provide strong evidence for new or enhanced expression of kinin B1 receptors in inflammation, and additionally the induction of kallikrein genes in angiogenesis and carcinoma. The results provide insights into possible roles of kallikrein inhibitors and kinin receptor antagonists.

Clinico-pathological study of causes of perinatal mortality in a developing country.

Perinatal mortality rates are an important indicator of the overall obstetric and neonatal services available, and the socio-economic status of the community. These rates are also used to identify shortcomings in services provided. The aim of this study was to identify clinical causative factors of perinatal deaths (supported by post mortem evidence where possible). This was a prospective descriptive study. The total number of deliveries and perinatal deaths over a 6-month period were recorded and clinico-demographic data noted. Post mortem examination information, if available, was also recorded. There was a total of 7789 deliveries over the 6-month period and 460 perinatal deaths, giving a perinatal mortality rate of 59/1000 deliveries; 45% (n = 207) of the perinatal deaths had post mortem examinations. The mean age was 26 years; 84.8% were single mothers. One-third of the group were un-booked: the mean gestational age of fetal death was 31 weeks, and the mean birth weight was 1700 g. Two-thirds of the perinatal deaths were stillbirths. The leading obstetric causes of deaths were: abruptio placentae (25.3%), hypertension in pregnancy (24.9%), prematurity (17.4%), unexplained stillbirth (13.4%) and intrapartum asphyxia (9.2%). The perinatal mortality rate of 59/1000 deliveries is high. Although this is comparable with other developing countries, there is a need for improvement in organisation of obstetric and neonatal care, staffing levels and access to and effective utilisation of antenatal services. These will probably lead to a significant reduction of this relatively high perinatal mortality rate.

Tissue kallikrein and kinins in renal disease.

The renal kallikrein-kinin system is involved in sodium and water homeostasis, blood pressure regulation and inflammation. Tissue kallikrein and kinin levels were measured in the urine of patients with renal disease and in the urine of living related kidney donors prior to uninephrectomy who served as controls. Tissue kallikrein and kinin B1 and B2 receptors were immunolocalised by confocal microscopy in renal biopsy material from patients with renal disease and controls (fresh autopsy material and normal kidney tissue from nephrectomies for malignancy). Urinary tissue kallikrein excretion was significantly decreased in patients with mild renal disease (16.6 +/- 6.7 ng tissue kallikrein (TK)/ng protein; p < 0.05) and more markedly so (1.8 +/- 0.7 ng TK/microg protein; p < 0.01) in patients with severe renal failure requiring dialysis compared to normal controls (78.9 +/- 31.7 ng TK/microg protein). Basal kinin values were unchanged in patients with renal disease (14 +/- 0.8 ng/ml) compared to controls (13.3 +/- 0.56 ng/ml). In control kidney tissue kallikrein was immunolocalised in the distal connecting tubules and collecting ducts whereas decreased immunolabelling was observed with renal disease. Kinin B2 receptor labelling was present in the entire nephron in the normal control kidney but was reduced with renal disease. While kinin B1 receptor immunolabelling was not observed in the control kidneys, labelling of distal tubules and collecting ducts was noted in renal disease, suggesting an upregulation of B1 receptors in renal parenchymal disease.

Correlation of kinin generating activity with Helicobacter pylori-associated gastric infection.

The kallikrein-kinin system involves a biologically complex set of interactive proteases that signal the first-line onset of inflammation and associated cellular processes. The basic enzymatic cleavage of kininogen substrate by the serine protease tissue kallikrein to liberate kinins is regulated by a number of factors. These may include the recently discovered bacterial involvement in the causation of gastritis. The gram-negative Helicobacter pylori organism, colonises the human gastric epithelium and initiates ulcerogenesis and may induce, in the longer term, tumour formation. The aim of this study was to investigate the role of kinins in H. pylori-induced gastric dyspepsia. During endoscopic examination, lavage aspirates of 23 patients were collected, and the tissue kallikrein content measured by a kinin-generating assay and an enzyme-linked immunosorbent assay. Gastric antral and pyloric biopsy tissue was histologically examined for degrees of inflammation and H. pylori infection, and then immunolabelled for tissue kallikrein and kinin receptors. Results show that labelled tissue kallikrein in the fundic glands and parietal cells of the diseased antrum was elevated with increasing severity of gastritis. Further, kinin-generating potential of the lavage fluid appeared to be greater with increasing evidence of infection. Tissue kallikrein immunosorbent assay levels were significantly raised in patients showing mild to moderate H. pylori infection. One outcome of this study may be the inclusion of kinin antagonists in management of gastric dyspepsia.

Immunolocalization of bradykinin receptors on human synovial tissue.

Kinins have been implicated in the pathogenesis of experimental and clinical inflammatory arthritis. Previous studies have reported increased amounts of plasma and tissue kallikreins in synovial fluid, raised kinin levels and an upregulation of kinin B2 receptors on synovial fluid neutrophils in rheumatoid arthritis. Bradykinin binding sites have been identified on human synovial cells by autoradiographic localization and Scatchard analysis. This study was undertaken to localize immunohistochemically kinin B1 and B2 receptors on human synovial tissue. Synovial tissue was obtained at the time of joint replacement surgery or arthroscopic synovectomy in six patients (two RA, two OA and two with avascular necrosis). Tissue sections were immunolabelled for kinin B1 and B2 receptors and viewed by light and confocal microscopy. No immunolabelling of the kinin receptors was observed in the method controls. In all patients labelling for kinin B2 receptors was observed in the synovial lining cells, fibroblasts and endothelial lining cells of blood vessels. There was no immunolabelling for kinin B1 receptors in all samples. These findings further support a role for the B2 receptors in joint diseases. There did not appear to be an induction of the kinin B1 receptor in human synovial tissue obtained from patients with chronic arthritis. However, further studies are required to assess the role of B1 receptors in active joint inflammation.

Kinin receptors in human vascular tissue: their role in atheromatous disease.

Using samples of many human blood vessels, obtained at autopsy and specific antibodies directed to peptide sequences of the kinin B1 and B2 receptors, we demonstrate the localisation of these receptors within the human vascular system using standard immunolabelling techniques. In large elastic arteries and veins, kinin receptors are present only in the endothelial cells whereas in all muscular arteries and arterioles, these receptors are present in both the endothelial and smooth muscle cells. The identification of kinin receptors in human blood vessels confirms that kinins may modulate both vascular permeability and contractility. The incidental finding at histology, of patchy atheromatous disease in the coronary, femoral, vertebral and pericallosal arteries, assisted in elucidating the role of these receptors in the commonest disease affecting human blood vessels. Intense labelling for B1 receptors was observed in the endothelial cells, foamy macrophages, inflammatory cells and fibroblasts within the thickened intima of the plaque as well as in smooth muscle cells of the underlying tunica media. Immunoreactive B2 receptors were also observed in these cells but with reduced intensity. The intense immunolabelling of B1 receptors in these regions suggest that these may be induced by atheromatous disease and may have therapeutic importance for the B1 receptor antagonists.

Kinin receptor status in normal and inflammed gastric mucosa.

No documented studies have been reported on the presence of B1 and B2 kinin receptors in the mammalian gastric mucosa. This first study aimed to immunolocalise sites of B1 and B2 kinin receptors in the human pyloric gastric mucosa and to evaluate its role in gastritis. Biopsies were obtained from patients with dyspepsia during endoscopic examination of the patient. The diagnosis and grading of the gastritis was performed on histological examination. Sections were immunostained for both B1 and B2 receptors using rabbit anti-human B1 and B2 kinin receptor antibodies. Control tissue was obtained from partial gastrectomy specimens, following surgical excision of the antrum for duodenal ulcers. The control antrum tissue showed strong immunoreactivity for kinin B2 receptors with positivity noted along the luminal border, at the base of the mucous and stem cells. The B1 receptor was not immunolocalised. Biopsies of all five patients with gastritis showed a decrease in immunolabelling of the B2 receptor and an induction of the B1 receptor especially in regenerating cells. In gastritis there is destruction of the normal mucosal glandular architecture with subsequent regeneration of the epithelial cells. The pyloric glands are infiltrated by acute inflammatory cells that cause crypt abscesses with loss of the epithelial cell membranes. This may explain the reduction in the immunolocalisation of the B2 kinin receptors and the induction of the B1 receptors in active gastritis. Follow up studies after treatment of the inflammation with a combination of B1/B2 kinin receptor antagonists are indicated.

The evaluation of tissue kallikrein in Helicobacter pylori-associated gastric ulcer disease.

Helicobacter pylori (Hp) associated ulcer disease is a common form of gastric disorder involving mucosal damage and invasion of the mucosa by polymorphic inflammatory cells with concomitant changes in the epithelial cell structure. The bacteria are thought to adhere by specific junction zones to the epithelial cell surface resulting in the degeneration of the mucosal layer. Our study was undertaken to examine the relative status of tissue kallikrein (TK) in antral and fundic biopsies, endoscopically obtained from 10 patients suspected of having gastric disorders. For histological evidence of inflammation the tissue was stained with hematoxylin and eosin and classified as mild, active, chronic and chronic active gastritis. Hp infection was determined by Giemsa staining. For localisation of TK, slide-mounted tissue sections were subjected to PAP and immunofluorescent staining using a goat anti-human TK IgG antibody. The results revealed that in the antral control tissue, removed during partial antractomy, TK was immunovisualised along the luminal border of the deep pyloric glands. The surface epithelia and superficial glands showed no labelling. The fundic control tissue revealed an absence of TK in the superficial and surface epithelial glands, but was positive in the parietal cells. The fundic biopsy specimens showed similar immunoreactivity in these areas. By contrast, in the inflammed pyloric mucosa, there was a shift of TK localisation to the basal part of the glandular cells and there was also expression of TK in the superficial glands that showed histological evidence of regeneration. In the fundic biopsies there was no change observed in the sites of TK localisation (similar to control tissue). It was observed, that even though 8 of the 10 subjects exhibited Hp infection, the inflamed mucosa showed no discernable difference in the staining patterns between the infected and non-infected tissue sections. Our findings suggest an important role for a B1/B2 kinin antagonist in patients with gastritis.

Tissue kallikrein in transplant kidney.

Literature survey, thus far, has shown a decrease in the excretion of urinary tissue kallikrein (TK) in transplant patients with a further reduction of the enzyme during episodes of acute rejection. The study aims were to compare, at cellular and subcellular levels, the localisation of tissue kallikrein in biopsies of the transplant kidney to autopsy derived normal renal tissue. Renal biopsies from eighteen transplant patients with deteriorating renal function were obtained. Immunolabelling for tissue kallikrein, using a polyclonal goat anti-TK, antibody raised against recombinant TK, was performed following routine enzymatic, immunofluorescence and electron microscopic techniques. In normal kidney tissue, TK was immunolocalised in the distal connecting tubules and collecting ducts. By comparison the renal transplant tissue showed a reduction in the intensity of label, but maintained the sites of localisation. In the sections examined by electron microscopy, although TK was confined mainly at the luminal side of the cell, some label was noted along the basolateral membranes. In the transplant kidneys, there was a reduction in the overall number of gold particles counted, which correlated with the decreased intensity observed on immunocytochemistry. In addition, there was a shift to a basolateral orientation of the immunolabel. Acute rejection is characterised by oedema, tubulitis and vasculitis. Destruction of the tubule cells and leakage of TK into the interstitial tissue space and the resultant effect of the formed kinins on renal capillary vasculature could explain the observed renal parenchymal oedema and transplant rejection.

Correlation between histological changes and loss of anionic charge of the glomerular basement membrane in early-onset pre-eclampsia.

This study morphometrically evaluates the glomerular anionic charge and examines the renal pathology in African women with early-onset pre-eclampsia. Polyethyleneimine-labelled anionic sites were decreased within the glomerular basement membrane in the early-onset pre-eclampsia group as compared with the control group (p < or = 0.02). A strong correlation (r = -0.76) was obtained between the number of anionic sites and the severity of proteinuria. Renal biopsy specimens revealed the coexistence of decreased glomerular charge with pathology of glomerular basement membrane, endothelial cells, foot processes, and mesangial cell proliferation. The loss of glomerular charge induces structural alterations of the glomerular filtration barrier and may be the mechanism responsible for proteinuria in early-onset pre-eclampsia.

Regional distribution of tissue kallikrein in the human brain.

Except for the localisation of tissue kallikrein (TK) in human prolactin secreting adenomas, its apparent deficiency in Alzheimer's disease and presence in human cerebrospinal fluid (CSF), the regional distribution of TK in human brain has not been defined. In this study on human brains collected within 24 h of death, we report on the regional distribution of TK in 24 different brain areas. The presence of TK was determined by its amidase and kininogenase activities, and the cellular localisation by immunocytochemistry. The highest amidolytic activity using the substrate D-ValLeuArg-pNA was recorded with extracts of the choroid plexus and hypothalamus, whereas extracts of the cerebral cortex (5 areas), cerebellum (3 areas), brain stem and thalamus possessed moderate amidolytic activity which correlated with the kininogenase assay. Immunoreactive TK has thus far been visualised in neurones of the hypothalamus, thalamus and reticular areas of the brain stem, as well as in cells of the anterior pituitary and choroid plexus by light and confocal microscopy. The cellular distribution of TK in specific areas suggests a role for TK in the neurones and epithelial cells of the brain. The question whether the functional importance of TK may relate to a particular cell type remains to be elucidated.

Leukocyte analysis of tubulointerstitial nephritis in primary membranoproliferative glomerulonephritis.

Cellular immune mechanisms may be involved in the pathogenesis of tubulointerstitial nephritis associated with several forms of primary glomerulonephritis. This study aims to characterize the mononuclear leukocytes infiltrating the interstitium in patients with primary membranoproliferative glomerulonephritis (MPGN) and correlates the degree and nature of the infiltrate with renal function. Cellular identification using monoclonal antibodies to leukocyte cell-surface antigens was conducted on renal biopsy specimens from 17 patients with type I primary MPGN (group 1) and 10 controls with various forms of nonproliferative glomerulonephritis (group 2). The majority (14) of the 17 patients in group 1 were black South Africans. Renal function was assessed at the time of renal biopsy. Patients with MPGN had a significant increase in the number of interstitial total leukocytes (LCA), T lymphocytes (T), and B lymphocytes (B) compared with controls. Although the interstitial monocyte (KP(1)) count was also increased in MPGN patients, the difference was not significant. Recorded numbers of cells per square millimeter in group 1 versus group 2 are as follows: LCA, 1306 +/- 1254 versus 138 +/- 91 (P<0.001); T, 638 +/- 547 versus 42 +/- 60 (P.0.01); B, 161 +/- 165 versus 57 +/- 50 (P=0.02); and KP(1), 125 +/- 153 versus 54 +/- 59 (P=0.17). As noted in previous studies, the T lymphocyte was the dominant cell, comprising 48.8% of the total count. However, the combined number of T lymphocytes, B lymphocytes, and monocytes accounted for only 70.6% of the total leukocytic interstitial count, implying that the majority of the remaining 29.4% of the cells were mononuclear leukocytes that did not express the antigens we stained for. There was a moderate correlation between the number of interstitial total leukocytes, and impairment of renal function as measured by both the serum creatinine (r = 0.43) and creatinine clearance (r = -0.41). This correlation also existed for the individual cells comprising the infiltrate and was strongest for T lymphocytes (r = 0.63) followed by monocytes (r =0.46) and B lymphocytes (r = 0.41). In conclusion, we have demonstrated a significant mononuclear leukocytic interstitial infiltrate in our patients with type I MPGN and a correlation between all cells of this infiltrate with impaired renal function. This correlation was strongest for the most frequently observed cell, the T lymphocyte.

Schwannoma of the posterior pharyngeal wall.

Schwannoma of the posterior pharyngeal wall, in a 36-year-old male patient is presented demonstrating the asymptomatic nature of the tumour (which is peculiar to schwannomas). The tumour gradually increased in size, destroyed the body of the third cervical vertebra but remained asymptomatic. The patient only presented to hospital when the tumour obstructed the airway, because of its large size.

Clinical features of malignant transformation in benign laryngeal papillomata.

Laryngeal papillomata can undergo spontaneous malignant transformation without being detected histologically and, in some instances, the disease may become so advanced, before the diagnosis is confirmed, that it is beyond any form of curative treatment. Because of this limitation imposed by histopathological investigation, a study was undertaken in 17 adults with benign laryngeal papillomata, (three of whom underwent malignant transformation) to determine whether malignant transformation can be predicted from the clinical behaviour of the tumour. The following features were analysed: age, sex, patient's symptoms, frequency of excision of the papillomata, site of lesion, presence or absence of laryngeal oedema, the need for tracheostomy, vocal fold mobility and presence or absence of cervical lymph nodes. It was found that decreased vocal fold mobility, the presence of cervical lymph nodes, exuberant and rapid growth requiring very frequent excisions, oedema of the larynx with airway obstruction requiring a tracheostomy are clinical features suggestive of malignant transformation.

Systemic lupus erythematosus and renal involvement. A South African experience.

Renal involvement in systemic lupus erythematosus (SLE) often signifies a poor prognosis. Whilst SLE appears to be not uncommon in the racial groups of South Africa, there are few reports in the literature. Between 1984 and 1987, 43 patients with SLE and nephritis were analyzed. Clinical and biochemical manifestations are described. The histological types (WHO classification) were mainly class II (15 cases) and class IV (17 cases). The ratio of black to Indian patients was 26.4% in class II and 43.4% in class IV to 42% each in class II and class IV respectively. Immunofluorescence showed a predominantly granular pattern of IgG, C1 and C3. Treatment was with combinations of prednisone and cyclophosphamide (14 cases), prednisone and azathioprine (21 cases) or pulse methylprednisolone (6 cases; total 41 cases). Two patients were not treated. There was no difference between cyclophosphamide and prednisone (14 cases) and prednisone with azathioprine (21 cases) treatment groups. The follow-up period was for 4 years. Mortality occurred in 15 patients (35%). The main cause of death was renal failure in 10 patients, infection in 1 patient and central nervous system involvement in 1 patient. The prognosis was worse in the Indian compared with the black patients. The WHO classification did not give an accurate prognosis regarding mortality in our study. Because of limited resources for the treatment of chronic renal failure in developing countries, we feel that patients with lupus nephritis should be treated with improved ancillary medical therapies and more effective immunosuppressive regimens.

Placental bed morphology in black women with eclampsia.

Histopathological changes in the placental bed were studied in 7 primigravid patients with eclampsia and compared with those in 17 normotensive patients. Normal morphological changes, which included trophoblastic invasion of spiral arterioles of the decidual and myometrial segments, were noted in the biopsy specimens taken from normotensive patients but were not seen in the specimens obtained from patients with eclampsia.

IgA nephropathy in blacks and Indians of Natal.

IgA nephropathy besides exhibiting a characteristic geographical distribution has been noted to have a low incidence in the blacks of the USA. There is a paucity of data on IgA nephropathy in the blacks of Africa. We report our findings among the blacks and compare these with Indians. An analysis of the primary glomerular diseases of 252 blacks and 75 Indians over 6 years (1981-1986) was done. Mesangiocapillary glomerulonephritis was the commonest type in the black (35.7%), whereas mesangial proliferative glomerulonephritis was the commonest in Indians (26.7%). IgA nephropathy occurred in 2 blacks (1 male, 1 female), whereas there were 10 Indians (8 males, 2 females). Available data among whites in Natal show that IgA nephropathy is not uncommon. HLA studies done in blacks with IgA nephropathy did not reveal the HLAB35 or the DR4 antigen. HLAB35 in our blacks is less common compared to Indians and whites of Durban. Thus, although glomerulonephritis is common in blacks, IgA nephropathy is rare. This suggests that infection which is common in our black population may not be responsible for the aetiology of IgA nephropathy. A dietary factor in the form of a high-fibre diet may protect the black population from IgA nephropathy. However, a genetic factor cannot be excluded.

Cyclosporin-associated nephropathy in patients with autoimmune diseases.

Renal biopsy specimens were evaluated from patients with different autoimmune diseases treated with cyclosporin (CyA). Ten biopsies were done before CyA, 10 biopsies after low-dose (less than 7.5 mg/kg/day, initial dose or mean daily dose within the first month, respectively), and 9 after high-dose (greater than 7.5 mg/kg/day) treatment. Definite chronic CyA nephrotoxicity (cyclosporin-associated arteriolopathy and/or interstitial fibrosis striped form with tubular atrophy) was only present in the initial high-dose group. In this group a significant serum creatinine increase was noted and 8 of the 9 patients were hypertensive. No significant correlation was found between the severity of morphologic lesions and the mean daily dose during total treatment, cumulative dose, and duration of therapy. The morphologic changes in the low-dose group did not differ from the control biopsy specimens before CyA treatment. Based on these results, it can be concluded that major nephrotoxicity can be avoided by initial low CyA doses.

Bullous systemic erythematosus. A case report.

Bullous disease in patients with systemic lupus erythematosus (SLE) has been previously described but characterization has been difficult. A case of bullous eruption that is an unusual manifestation of SLE rather than a primary vesiculobullous eruption is described. The patient was successfully treated with dapsone.