Continuing observations on the regulatory effects of donor-specific bone marrow cell infusions and chimerism in kidney transplant recipients

BACKGROUND

Continued follow-up of a series of donor bone marrow cell (DBMC)-infused first cadaver renal transplant recipients is described (n=58), now at a 36-month actuarial time point postoperatively. Serial polymerase chain reaction-flow cytometry (PCR-Flow) and cellular immune assays of iliac crest bone marrow aspirates and peripheral blood have begun to be compared with concomitantly transplanted recipients of living-related donor (LRD) kidneys and donor marrow infusions given the same immunosuppressive regimen (n=16). There have also been comparisons (36 months) with 188 controls transplanted concomitantly, i.e., recipients of first cadaver kidney transplants, who did not receive bone marrow.

METHODS

Each group was given equivalent immunosuppressive regimens of OKT3 anti-T cell induction and maintenance tacrolimus, mycophenolate mofetil, and methylprednisolone. Actuarial patient and graft survival have been 96% and 93%, respectively, in the controls and 91% and 91%, respectively, in the DBMC-infused recipients. Trough levels of tacrolimus were significantly lower in the DBMC-infused group.

RESULTS

In PCR-Flow measurements, in peripheral blood up to 6 months postoperatively, there were higher levels of chimerism, i.e., in the total number of donor cells, as well as the donor CD3+ and CD34+ subsets in the LRD recipients administered DBMC infusions, compared with cadaver DBMC recipients, supporting the notion of a positive effect of histocompatibility on chimerism levels. In PCR-Flow measurements of recipient iliac crest bone marrow aspirates as in previous studies on peripheral blood, early acute rejection episodes (<1 month) were found to be associated with a later (6-14 months) decrease in donor cell lineage chimerism. However, a trend toward recovery of chimeric levels occurred by 21-28 months in a second iliac crest marrow aspirate 1 year after the first aspirate in the DBMC-infused recipients who experienced such early rejection episodes. This was in contrast to the controls in whom there were sustained low levels of iliac crest bone marrow chimerism at both the earlier and later intervals (i.e., no chimeric recovery), with 17/183 surviving controls progressing into chronic rejection. This has not yet been seen in the DBMC-infused group (0/54). In in vitro observations on cellular immune reactivity at 1 year postoperatively, decreased peripheral blood lymphocyte proliferative reactions were seen in response to phytohemagglutinin and Staph-A mitogens, as well as to cytomegalovirus and Epstein-Barr viral protein antigens in the DBMC-infused group versus the controls. Chronic immunosuppression did not seem to effect a vigorous in vitro inhibitory (regulatory) activity of bone marrow taken from these transplant recipients 2 years postoperatively in mixed lymphocyte culture and cell-mediated lympholysis reactions, using allogeneic responding cells from "normal" laboratory volunteers. Autologous peripheral blood lymphoproliferative responses to phytohemagglutinin and Staph-A mitogens, as well as to cytomegalovirus and Epstein-Barr virus protein antigens, were also regulated by either organ donor (non-immunosuppressed) bone marrow cells or by transplant recipient (immunosuppressed) bone marrow cells. What appeared to be disparate between the DBMC-infused and control groups (both immunosuppressed) was the trend for the (autologous) bone marrow suppressive effect on antiviral lymphoproliferative responses, to be stronger in the DBMC-infused group, who also had significantly (>one order of magnitude) higher levels of chimerism (P=0.01).

CONCLUSIONS

It is concluded that the establishment of a chimeric state in DBMC-infused recipients, albeit of relatively low magnitude (approximately 1% at 2 years in recipient iliac crest bone marrow), has had a definite regulatory effect on immune responses. These results, therefore, add weight to the "causal" horn of the dilemma as to whether donor cell chimerism is a cause or an effect of

Intramedullary spinal cord metastasis : an under-diagnosed entity

Intramedullary spinal cord metastatic tumours, generally considered to be rare, are increasingly being diagnosed due to aggressive management of the primary malignancy, better imaging facilities and attempts at total excision of these lesions. Sincethese lesions were diagnosed late in the course of the disease patients were earlier given only palliative treatment. Presently, with more intensive treatment protocols the immediate outcome appears to be better.The present report is about two patients in whom the spinal cord lesion was the primary manifestation of an underlying malignancy. Total excision of the lesion was done in both the patients. Post operatively, one patient had marked improvement in the neurological status. He underwent radiation and chemotherapy and survived for seven months. He later succumbed to multiple secondaries involving the brain. The other patient did not improve in her neurological function in the immediate post-operative period and was lost to follow up.

Macrophage and hepatic stellate cell responses during experimental hepatocarcinogenesis

The aim of the study was to assess the monocyte/macrophage and hepatic stellate cell responses during experimental diethylnitrosamine (DEN)-induced hepatocarcinogenesis. Diethylnitrosamine (50mg/L) was administered to 39 rats for 10 weeks; liver tissue was obtained at weeks 10, 16 and 19. In this model, necroinflammatory damage occurs during the period of DEN administration but thereafter subsides; dysplastic nodules and carcinomas subsequently develop. Monocytes/ macrophages were detected immunohistochemically using ED1 and ED2 monoclonal antibodies; hepatic stellate cells (HSC) were detected using antibodies to alpha-smooth muscle actin (alpha-SMA) (activated HSC) and glial fibrillary acidic protein (GFAP). Parenchymal ED1- and ED2-positive monocytes/macrophages and alpha-SMA-positive HSC increased at week 10 when there was ongoing DEN-induced necroinflammatory activity. ED1- and ED2-positive cells were also prominent at weeks 16 and 19, particularly around the periphery of dysplastic and carcinomatous nodules, with occasional macrophages between dysplastic hepatocytes. alpha-SMA-positive HSC were present within sinusoids between dysplastic cells and were more abundant at weeks 16 and 19 than in control or week 10 animals. Activated HSC were prominent in fibrous septa around and within dysplastic and carcinomatous nodules at weeks 16 and 19. In contrast, GFAP-positive HSC did not accumulate in developing septa or within dysplastic and carcinomatous nodules. We have demonstrated changes in the monocyte/ macrophage and HSC populations during the development of hepatocellular dysplasia and carcinoma at time points when there is little necroinflammatory activity; this may therefore represent a host response to hepatocyte dysplasia. The HSC activation may be mediated, in part, by monocyte/ macrophage-derived factors, but we speculate that it may also result from direct stimulation by factors released from dysplastic hepatocytes.

Hepatitis G virus does not cause significant liver disease after liver transplantation

The aim of this study was to determine the prevalence of infection with the newly described hepatitis G virus (HGV) in a liver transplant cohort, and to establish the frequency and nature of hepatitis in those with and without HGV infection. A reverse transcriptase-polymerase chain reaction technique was employed to determine viraemia in the patients, and liver biopsies taken at different times after transplantation were assessed histologically. Hepatitis G virus RNA was detected in 47% of the liver transplant recipients investigated. Those positive for HGV had received significantly more blood or blood products than the HGV-negative patients. The frequency of abnormal liver function tests was similar in HGV-positive and HGV-negative recipients. Bile duct epithelial cell damage was more frequently seen in those with HGV viraemia. This study indicates that almost half of the liver transplant recipients in Northern England are positive for HGV, and that infection is associated with exposure to blood and blood products. It appears that, in the immunosuppressed patient, HGV does not cause clinically significant liver disease, at least up to 2 years after transplantation. If HGV infection is associated with hepatitis outside this clinical setting, it is likely that the liver damage is immunopathologically mediated rather than as a result of direct viral cytotoxicity.

Clinical and angiographic findings in black patients with suspected coronary artery disease

To determine the clinical variables and coronary angiographic findings in black patients with suspected coronary artery disease, we analyzed the data on consecutive black patients undergoing their first coronary angiogram over a three year period at the Cook County Hospital, Chicago, Illinois. We compared these findings to those of black and white patients from previous studies. There were 654 patients with a mean age+/-standard deviation of 56+/-10 years; 309 (47%) were men. Two hundred nineteen patients (33%) presented with unstable angina, 75 patients (12%) with acute myocardial infarction and 338 patients (52%) with chronic stable angina. Three hundred forty-six patients (53%) had 50% or greater stenosis in at least one of the major vessels. Among the patients with coronary artery disease, 128 patients (37%) had one vessel disease, 102 patients (29%) had two-vessel disease, and 116 patients (34%) had three-vessel disease. Black patients who undergo coronary angiography for suspected coronary artery disease have a high frequency of normal coronary angiogram or non-obstructive coronary artery disease. The frequency of 1-, 2- and 3-vessel disease in blacks with coronary artery disease is comparable to those observed in whites in previous reports.

Autoimmune hepatitis in older patients

AIM

autoimmune hepatitis (AIH) is thought to present rarely in old people. The aims of the present study were to (i) review individuals diagnosed clinically as having AIH presenting over or under 65 years of age at Freeman Hospital, Newcastle, from 1979 to 1993 and (ii) compare diagnostic and histological scores, treatment and outcome, and hence provide a useful profile of the disease in older patients.

METHODS

310 individuals with a histological diagnosis of chronic hepatitis were identified, and review of the medical notes of 286 revealed 54 with a diagnosis of AIH. Of these, 12 (22%) were > or =65 years of age at presentation.

RESULTS

at presentation, the mean diagnostic score (according to the diagnostic scoring system devised by an international panel; maximum score, 17) of the whole group was 11.5 (SD 3.5) and the mean score for those > or =65 years was 9 (SD 3). The mean histological grade (intensity of necro-inflammatory activity; maximum, 18) for the elderly group was 6 (SD 2) compared with 4.5 (SD 0.5) for the whole group. Despite this, 42% of the elderly sufferers had received no immunosuppressive therapy (versus 12% of the younger group). At follow-up, 26% in both groups had developed cirrhosis. None of the elderly group (but 7% of the younger group) had died from complications of chronic liver disease.

CONCLUSION

we present data on 12 patients presenting at 65 years and over with AIH. In elderly individuals diagnosis may be more difficult, and treatment appears often to have been withheld. Despite this, and the more severe initial histological grade, the prognosis appeared no worse than in younger, usually correctly treated, patients.

Ludwig's angina

A 13 year review of patients diagnosed to have Ludwig's angina admitted to the Christian Medical College and Hospital, Vellore, India, between March 1982 and April 1995 is presented. The patients were either admitted to the ENT or paediatric surgical units. There were 41 patients, 24% being children and 76% adults. The clinical profile and outcome of these two groups were compared. In the paediatric group, none had dental caries while in the adult group, 52% had associated dental caries. In children, 70% were controlled with conservative medical management unlike the adults of whom 81% needed incision and drainage. Tracheostomy was necessary in 10% of the children and in 52% of the adults. The mortality was 10% in both groups.

Pseudohypophosphatasia

Two rare cases of pseudohypophosphatasia in two siblings which so far, to best of our knowledge have not been reported.

The effects of chimeric cells following donor bone marrow infusions as detected by PCR-flow assays in kidney transplant recipients

40 recipients of first cadaver kidney transplants were given perioperative donor vertebral bone marrow infusions (DBMC), compared with 100 controls who did not receive donor bone marrow. The immunosuppressive regimen included OKT3, Tacrolimus, and steroid maintenance therapy, and, in some patients, newly introduced mycophenolate mofetil. This report describes the 24-mo actuarial follow-up and several immunological monitoring studies including sequential measurements of donor bone marrow lineage subset chimerism by the recently reported PCR-flow assay. This is a sensitive in situ PCR detection system for donor versus recipient histocompatibility genes as well as cell surface CD epitope markers using flow cytometry. The results indicate (a) the stabilization of the donor CD3+ and CD34+ cells in recipient peripheral blood at levels below 1% between 6 mo and 1 yr postoperatively, with a 10-fold higher level of donor cell chimerism of these lineages in recipient iliac crest marrow; (b) significantly lower levels of chimerism in peripheral blood up to 6 mo postoperatively in patients who had early acute (reversible) rejection episodes compared with those who did not; (c) a higher degree of chimerism seen in patients who were class II MHC HLA DR identical with their donors; (d) the identification of a high proportion of the donor bone marrow derived CD3 dimly staining subset of T cells (to which regulatory functions have been ascribed) in recipient peripheral blood and especially in recipient bone marrow; and (e) an unexpectedly increased susceptibility to clinically significant infections (primarily viral), and even death in the DBMC-infused group, compared with controls, but no graft losses because of rejection in the DBMC-infused group. Mixed lymphocyte culture assays showed a trend toward a greater number of nonspecifically low reactors in the DBMC group, as well as a greater number of nonspecifically high reactors in the controls (P = 0.058). The autologous mixed lymphocyte reaction also indicated a trend towards nonspecific immune activation in the DBMC group. Finally, anti-cytomegaloviral IgG antibody reactivity was significantly inhibited in the DBMC group 4-6 mo postoperatively (P = < 0.05). In the controls, there were no donor cell lineages detected by PCR-flow in the peripheral blood. These rather unexpected findings, indicating a more depressed cellular and humoral immune capacity in the DBMC cadaver kidney transplant recipients in this relatively early follow-up period, are discussed relevant to chimerism, MHC restriction, and suppressor activity brought about by specialized DBMC subsets, which still need to be defined.

Etiology and characteristics of congestive heart failure in blacks

In this study of 301 black patients with congestive heart failure (CHF), systemic hypertension is the most common cause of CHF and is the primary etiology of CHF in 61%. Left ventricular hypertrophy is highly prevalent and is seen in 63% of the patients who had an echocardiogram.

Hepatocyte growth factor levels in liver and serum increase during chemical hepatocarcinogenesis

Hepatocyte growth factor (HGF) is mitogenic for hepatocytes and some tumor cell lines. Elevations in plasma HGF levels have been detected in patients with hepatocellular carcinoma (HCC), and it is possible that HGF is involved in the promotion and/or progression of tumor growth. We measured serum and liver tissue HGF levels during chemically induced hepatocarcinogenesis. Wistar rats were given diethylnitrosamine (DEN) in drinking water for 10 weeks with controls receiving drinking water only. Animals were killed at 10, 16, and 19 weeks. Liver HGF levels were determined from immunoblotted protein by scanning densitometry, and serum HGF levels were measured by sandwich enzyme-linked immunosorbent assay (ELISA). HGF was also immunolocalized in fixed liver tissue sections. In DEN-treated animals, at 10 weeks, there was necroinflammation but no dysplasia. Serum HGF was elevated compared with controls (P < .001) but there was no increase in liver HGF. At 16 weeks, there was liver cell dysplasia with minimal necroinflammation; serum and tissue HGF levels were both significantly elevated above controls. At 19 weeks, hepatocellular carcinomas (HCC) were present in five of six DEN-treated animals; liver HGF (P < .05) and serum HGF (P < .001) were both elevated compared with controls. HGF was localized in basement membranes around bile ducts and vessels and some perisinusoidal cells. Increased HGF immunolabeling was observed at 16 and 19 weeks, but dysplastic hepatocytes and tumor cells were HGF-negative. HGF may serve as a growth promoter at early stages during liver tumor development acting through possibly endocrine and paracrine pathways. Recent observations have described HGF as being mitoinhibitory for HCC cell lines; it is possible therefore that the continued up-regulation of HGF in the latter stages of our DEN model may inhibit tumor cell growth, and thus represent a form of antitumor host response.

Multicenter study of target-controlled infusion of propofol-sufentanil or sufentanil-midazolam for coronary artery bypass graft surgery. Multicenter Study of Perioperative Ischemia (McSPI) Research Group

BACKGROUND

The use of target-controlled infusions of anesthetics for coronary artery bypass graft surgery has not been studied in detail. The effects of target-controlled infusions of propofol or sufentanil, supplemented by infusions of sufentanil or midazolam, respectively, were evaluated and compared.

METHODS

At 14 clinical sites, 329 patients were given a target-controlled infusion of propofol (n = 165) to produce effect-site concentration (Ce) of > or = 3-micrograms/ml or a target-controlled infusion of sufentanil (n = 164). Sufentanil or midazolam, respectively, also were infused. Systolic hypertension, hypotension, tachycardia, and bradycardia were assessed by measuring heart rate and blood pressure every minute during operation. Myocardial ischemia was assessed perioperatively by monitoring ST segment deviation via continuous three-lead Holter electrocardiography, and it was evaluated during operation by monitoring left ventricular wall motion abnormality via transesophageal echocardiography.

RESULTS

The measured cardiovascular parameters were satisfactory and usually similar for the patients receiving propofol-sufentanil or sufentanil-midazolam. The primary endpoint of the percentage of patients with intraoperative ST segment deviation (23 +/- 6% vs. 24 +/- 6%, P = 0.86) did not differ significantly between the two groups. The incidence of left ventricular wall motion abnormality shown on transesophageal echocardiography before (19 +/- 4% vs. 26 +/- 4%, P = 0.25) and after (23 +/- 4% vs. 31 +/- 5%, P = 0.32) cardiopulmonary bypass also did not differ significantly for the two groups. Changes in intraoperative target concentration were more frequent with propofol-sufentanil anesthetic than with sufentanil-midazolam (11.7 +/- 7.1 vs. 7.3 +/- 3.6, P < 0.001). The incidence of intraoperative hypotension (77% vs. 55%, P < 0.001), the use of inotropic/vasopressor medications (93% vs. 84%, P = 0.01), and the administration of crystalloids (2.8 +/- 1.4 L vs. 2.4 +/- 1.2 L, P < 0.001) were significantly greater in the propofol-sufentanil group. Conversely, the incidence of intraoperative hypertension (43% vs. 54%, P = 0.05) and the use of antihypertensive/vasodilator medications (70% vs. 90%, P < 0.001) were significantly less in the propofol-sufentanil group.

CONCLUSIONS

Target-controlled infusions of propofol or sufentanil, supplemented by infusions of sufentanil or midazolam, respectively, were suitable to provide anesthesia for coronary artery bypass graft surgery. Continuous monitoring revealed a high prevalence of hemodynamic abnormalities. Despite greater hypotension in the propofol-sufentanil group and greater hypertension in the sufentanil-midazolam group, episodes of myocardial ischemia were similar for both groups and were not temporally related to episodes of hemodynamic abnormalities.

CD44 is expressed in hepatocellular carcinomas showing vascular invasion

CD44 and its variant isoforms are a group of transmembrane glycoproteins which play important roles in immune recognition, in lymphocyte trafficking, and in cell-cell and cell-matrix interactions. Although CD44 is expressed by some normal human epithelial and mesenchymal cells, upregulation of CD44 expression has been related to the metastatic potential of some malignant tumours. In this study of 27 hepatocellular carcinomas (HCCs), an indirect immunohistochemical method was used to investigate the distribution of CD44 in normal liver and to determine whether expression of the standard form of CD44 (CD44s), or two of its variant isoforms (CD44-v3 and CD44-v6), correlated with tumour grade, proliferation indices, or histological evidence of vascular invasion. Fifteen of the tumours were Edmondson grade II, four were grade III, and eight were grade IV. Liver cell dysplasia was present in adjacent liver parenchyma in three cases and vascular invasion was observed in ten HCCs. Vascular invasion was found to be more frequent in high grade HCCs and a significant correlation was observed between tumour proliferation indices and vascular invasion. CD44s was not expressed by epithelial cells of normal liver but was expressed by tumour cells in six HCCs; vascular invasion was present in five of these HCCs. Three CD44s-positive cases also expressed CD44-v3 and two of these also expressed CD44-v6. CD44 was not expressed in areas of hepatocyte dysplasia. There was a significant correlation between CD44 expression and the presence of vascular invasion, but not between CD44 expression and tumour grade or tumour proliferation indices. It is concluded that upregulation of cell surface CD44 expression on malignant hepatocytes is related to their tendency to vascular invasion and may have implications relating to metastasis and prognosis in patients with HCCs.

CD44 is expressed in hepatocellular carcinomas showing vascular invasion

CD44 and its variant isoforms are a group of transmembrane glycoproteins which play important roles in immune recognition, in lymphocyte trafficking, and in cell-cell and cell-matrix interactions. Although CD44 is expressed by some normal human epithelial and mesenchymal cells, upregulation of CD44 expression has been related to the metastatic potential of some malignant tumours. In this study of 27 hepatocellular carcinomas (HCCs), an indirect immunohistochemical method was used to investigate the distribution of CD44 in normal liver and to determine whether expression of the standard form of CD44 (CD44s), or two of its variant isoforms (CD44-v3 and CD44-v6), correlated with tumour grade, proliferation indices, or histological evidence of vascular invasion. Fifteen of the tumours were Edmondson grade II, four were grade III, and eight were grade IV. Liver cell dysplasia was present in adjacent liver parenchyma in three cases and vascular invasion was observed in ten HCCs. Vascular invasion was found to be more frequent in high grade HCCs and a significant correlation was observed between tumour proliferation indices and vascular invasion. CD44s was not expressed by epithelial cells of normal liver but was expressed by tumour cells in six HCCs; vascular invasion was present in five of these HCCs. Three CD44s-positive cases also expressed CD44-v3 and two of these also expressed CD44-v6. CD44 was not expressed in areas of hepatocyte dysplasia. There was a significant correlation between CD44 expression and the presence of vascular invasion, but not between CD44 expression and tumour grade or tumour proliferation indices. It is concluded that upregulation of cell surface CD44 expression on malignant hepatocytes is related to their tendency to vascular invasion and may have implications relating to metastasis and prognosis in patients with HCCs.

CD44 is expressed in hepatocellular carcinomas showing vascular invasion

CD44 and its variant isoforms are a group of transmembrane glycoproteins which play important roles in immune recognition, in lymphocyte trafficking, and in cell-cell and cell-matrix interactions. Although CD44 is expressed by some normal human epithelial and mesenchymal cells, upregulation of CD44 expression has been related to the metastatic potential of some malignant tumours. In this study of 27 hepatocellular carcinomas (HCCs), an indirect immunohistochemical method was used to investigate the distribution of CD44 in normal liver and to determine whether expression of the standard form of CD44 (CD44s), or two of its variant isoforms (CD44-v3 and CD44-v6), correlated with tumour grade, proliferation indices, or histological evidence of vascular invasion. Fifteen of the tumours were Edmondson grade II, four were grade III, and eight were grade IV. Liver cell dysplasia was present in adjacent liver parenchyma in three cases and vascular invasion was observed in ten HCCs. Vascular invasion was found to be more frequent in high grade HCCs and a significant correlation was observed between tumour proliferation indices and vascular invasion. CD44s was not expressed by epithelial cells of normal liver but was expressed by tumour cells in six HCCs; vascular invasion was present in five of these HCCs. Three CD44s-positive cases also expressed CD44-v3 and two of these also expressed CD44-v6. CD44 was not expressed in areas of hepatocyte dysplasia. There was a significant correlation between CD44 expression and the presence of vascular invasion, but not between CD44 expression and tumour grade or tumour proliferation indices. It is concluded that upregulation of cell surface CD44 expression on malignant hepatocytes is related to their tendency to vascular invasion and may have implications relating to metastasis and prognosis in patients with HCCs.

Transforming growth factor-alpha expression is altered during experimental hepatocarcinogenesis

In order to characterize the role of transforming growth factor-alpha (TGF alpha) during hepatocarcinogenesis, liver tissue was examined at 10, 16, and 19 weeks following initial 10-week diethylnitrosamine (50 mg l-1 drinking water) exposure in female Wistar rats. Liver tissue protein extracts were electrophoresed and transferred to nitrocellulose filters. Levels of tissue-derived TGF alpha and epidermal growth factor receptor (EGFr) were assessed using an anti-TGF alpha monoclonal antibody (Ab-1) and an anti-EGFr polyclonal antibody (AB-4), coupled with scanning densitometric quantification. Immunolocalization of TGF alpha was performed in Bouin's-fixed, paraffin-embedded liver tissue sections. The distribution and intensity of TGF alpha immunoreactivity varied according to the degree of dysplasia, severely dysplastic cells being strongly immunoreactive. At week 10, mild hepatocyte dysplasia and perivenular inflammation were evident, together with a corresponding increase in perivenular TGF alpha immunoreactivity. By week 16, foci of moderate to severe dysplasia were observed; at this stage, there was a decrease in perivenular immunoreactivity but a further increase in overall liver tissue TGF alpha levels. Some 'altered foci' and dysplastic nodules showed intense immunoreactivity for TGF alpha. At these time points, immunodetectable liver EGFr was found to decrease significantly in comparison with normal control tissue. TGF alpha immunoreactivity was observed in fully developed carcinomas at week 19, although some tumours were negative by immunohistochemistry. The up-regulation of immunodetectable TGF alpha and the concomitant down-regulation of EGFr demonstrated positive (P < 0.01) and negative (P < 0.001) correlations, respectively, with hepatocyte proliferation indices. These findings suggest that the TGF alpha/EGFr ligand receptor system may be important during tumour promotion and in the stimulation of continued proliferation in hepatocellular carcinomas.

CD44 is expressed in hepatocellular carcinomas showing vascular invasion

CD44 and its variant isoforms are a group of transmembrane glycoproteins which play important roles in immune recognition, in lymphocyte trafficking, and in cell-cell and cell-matrix interactions. Although CD44 is expressed by some normal human epithelial and mesenchymal cells, upregulation of CD44 expression has been related to the metastatic potential of some malignant tumours. In this study of 27 hepatocellular carcinomas (HCCs), an indirect immunohistochemical method was used to investigate the distribution of CD44 in normal liver and to determine whether expression of the standard form of CD44 (CD44s), or two of its variant isoforms (CD44-v3 and CD44-v6), correlated with tumour grade, proliferation indices, or histological evidence of vascular invasion. Fifteen of the tumours were Edmondson grade II, four were grade III, and eight were grade IV. Liver cell dysplasia was present in adjacent liver parenchyma in three cases and vascular invasion was observed in ten HCCs. Vascular invasion was found to be more frequent in high grade HCCs and a significant correlation was observed between tumour proliferation indices and vascular invasion. CD44s was not expressed by epithelial cells of normal liver but was expressed by tumour cells in six HCCs; vascular invasion was present in five of these HCCs. Three CD44s-positive cases also expressed CD44-v3 and two of these also expressed CD44-v6. CD44 was not expressed in areas of hepatocyte dysplasia. There was a significant correlation between CD44 expression and the presence of vascular invasion, but not between CD44 expression and tumour grade or tumour proliferation indices. It is concluded that upregulation of cell surface CD44 expression on malignant hepatocytes is related to their tendency to vascular invasion and may have implications relating to metastasis and prognosis in patients with HCCs.

Analysis of the D1S80 (pMCT118) VNTR locus polymorphism in a native Kuwaiti population by the polymerase chain reaction

We have determined the allele and genotype frequencies at the hypervariable locus D1S80 in a native Kuwaiti population using the polymerase chain reaction technique and subsequent high resolution gel electrophoresis. In a sample of 200 individuals, 21 alleles and 57 genotypes were detected. The alleles with 18 and 24 repeat units were most common with frequencies of 0.188 and 0.408 respectively. The distribution of the observed genotypes was in agreement with the Hardy-Weinberg equilibrium prediction. The observed heterozygosity for the population sample was 0.80 with the allelic diversity of 0.781 +/- 0.029 and the power of discrimination was 0.94. The data obtained in this study are potentially useful for individual identification in forensic casework.