Clonal expansion within the CD4+CD57+ and CD8+CD57+ T cell subsets in chronic lymphocytic leukemia

The role of T cells in chronic lymphocytic leukemia (CLL) has not been extensively investigated, since the most prominent cellular abnormality in CLL involves the clonal expansion of B cells. In this study we have undertaken a comprehensive analysis of the CD4+ and CD8+ T cell repertoire in a population of CLL patients (n = 19) and age-matched controls (n = 22). The TCR repertoire analysis was performed using a multiplex PCR assay for CDR3 length, an approach that allows for the detection of underlying oligoclonality in complex T cell populations. We established that oligoclonality was substantially more frequent in both the CD4+ and CD8+ T cell populations of CLL patients than in the age-matched controls (p < 0.001). Using three-color FACS analysis with a panel of TCRV segment-specific mAbs, we also established that oligoclonal expansions are predominantly found in the CD57+ subset of both the CD4+ and CD8+ T cell populations. The frequency of the CD57 marker on CD4+ T cells was increased in the setting of CLL (% CD57 = 14.8 +/- 13.0%) compared with that in normal controls (% CD57 = 3.3 +/- 3.0%; p < 0.001). An elevated frequency of CD4+CD57+ T cells was correlated with more advanced disease. Similarly, the most extreme oligoclonal expansions of CD4+CD57+ T cells occurred in CLL patients who had progressed beyond Rai stage 0. These data document profound alterations in the T cell repertoire of CLL patients and point to a role for clonal T cell populations in the pathogenesis of this disease.

Spinal angiolipomas revisited: two case reports

Approximately 60 cases of spinal angiolipomas have been described in the medical literature. Extradural tumours predominate. Lesions with a bony component, the infiltrating subgroup, were reported in 10 patients. Intradural angiolipomas were found three times. Several excellent review articles are available, but a systematic comparison of the characteristics of the two major varieties, infiltrating and non-infiltrating spinal extradural angiolipomas, has not so far been made. The authors operated on two patients with spinal angiolipomas and found one of them the infiltrating and the other the non-infiltrating type. Then, they proceeded to a review of all publish cases of infiltrating angiolipomas. With a knowledge of recently reported data on the subject the authors compared essential clinical features of both varieties of tumours. They share identical clinical characteristics. Differences found in age, sex or location were not statistically significant. Mode of onset and signs and symptoms present on admission were essentially similar. As could be anticipated, removal was more often complete in non-infiltrating tumours, but outcome was good or fair in more than 85% of cases in both groups. Involvement of bone by spinal angiolipomas does not imply a worsening in the prognosis.

[Acute cerebrovascular disorder and arterial hypertension. Prospective study with 248 patients]

OBJECTIVE

To evaluate the hypertension associated to different types and sub-types of cerebrovascular disease (stroke), with particular reference to the frequency of hypertension, the values of blood pressure, the risk factors and the involvement of other target organs.

DEFINITION

Prospective study in 248 patients with acute stroke admitted to a Clinical Medicine Unit in three independent time periods.

SETTING

Internal Medicine Clinic of University Hospital in Lisbon.

METHODS

Medical, neurological and cardiologic examination were performed and all patients were also submitted to different complementary tests, including a computer tomography scan of the brain, and an echocardiogram. The values of blood pressure were measured in the admission at the urgent service and 24 h after in the the ward. We identified three sub-types of stroke: intracerebral hemorrhage (IH), ischaemic stroke (IS) and lacunes (L). For each sub-type and for those with hypertension or not, we evaluated: age, sex, duration of stay in hospital and mortality. We also compared for each sub-type the values of blood pressure, the risk factor and the repercussion on other target organs.

PATIENTS

Two hundred and forty eight patients (52% were men) with mean age 68.0 +/- 10.2 years, and ages among 40 and 92 years. Thirty-seven patients (15%) died.

MAIN RESULTS

In the entire population (n = 248) hypertension were more prevalent in IH 83% and L 82% than in IS 59% (p < 0.0005). Hypertension was present in 172 patients (69%) and 81 (47%) were IS, 58 (34%) L and 33 (19%) IH. Sixty six percent of the 172 patients with hypertension had at least another risk factor and the most aged ones (> 65 years old) were more frequent in IS 75% than in HI 45% or L 58% (p < 0.001). For all subtypes blood pressure measurements were higher in admission than in ward and they were also higher in IH than in IS (p < 0.05). Hypertensive cardiopathy was more prevalent in IH 76% and L 61% than in IS 49% (p < 0.05). Renal failure was more frequent in IS 37% than in IH 28% and L 17% (p < 0.05).

CONCLUSIONS

Hypertension is very frequent, and like advanced age is a major risk factor of stroke. Hypertension is frequently associated with one or more risk factors. Hypertensive cardiopathy is more related with IH and L and the renal involvement with IS.

Oligoclonality of CD8+ T cells in health and disease: aging, infection, or immune regulation?

Oligoclonality of the CD8+ T cell subset is a common and characteristic feature of the normal human peripheral T cell repertoire. These clonally expanded populations are predominantly found in a CD57+ or CD28- CD8+ T cell subset. While CD8 oligoclonality is somewhat more common in the older age group, it is also very prevalent in young to middle-aged adults. Recent experiments have also demonstrated that the clonally expanded populations may actually occur in two distinct subpopulations of CD8+ CD28- cells, distinguished by the expression of the CD57 surface marker. A major difficulty with studies involving CD8+ CD28- CD57+ T cells is their relative lack of proliferative capacity. We have recently investigated the possibility that this phenotype may be due to a state of "replicative senescence" in some cases. In this regard, we have demonstrated that the telomere lengths of CD8+ CD28- T cells are generally shorter than that of their CD8+ CD28+ counterparts, consistent with a distinct replicative history for the CD8+ CD28- population. Additional studies of the normal biology of clonally expanded CD8+ T cells are likely to yield important insights into immune function in health and disease.

Shortened telomeres in clonally expanded CD28-CD8+ T cells imply a replicative history that is distinct from their CD28+CD8+ counterparts

Long term in vitro culture of clonally expanded CD8+T cells, generally found within the CD57+ or CD28-subset, has generally been unsuccessful, suggesting that these cells may have a limited replicative potential. Telomeric shortening may reflect the action of a "mitotic clock" regulating the number of divisions a cell can undergo. In this study, we have compared the telomeric lengths of CD28-CD8+ and CD28+CD8+ T cells in 10 normal individuals to assess their replicative history. Overall, the telomeric lengths were found to be significantly shorter in the CD28-CD8+ T cell subset compared with the CD28+CD8+ subset. Furthermore, clonally expanded TCRBV11+CD8+ T cells from an individual exhibited telomeric lengths that were 2.9 kb shorter than those found in the polyclonal CD28+CD8+ T cell subset. These findings indicate that clonally expanded CD28-CD8+ T cells have undergone many more rounds of replication than CD28+CD8+ T cells, and consistent with the loss of CD28 expression, they may have reached a state of replicative senescence.

Shortened telomeres in clonally expanded CD28-CD8+ T cells imply a replicative history that is distinct from their CD28+CD8+ counterparts

Long term in vitro culture of clonally expanded CD8+T cells, generally found within the CD57+ or CD28-subset, has generally been unsuccessful, suggesting that these cells may have a limited replicative potential. Telomeric shortening may reflect the action of a "mitotic clock" regulating the number of divisions a cell can undergo. In this study, we have compared the telomeric lengths of CD28-CD8+ and CD28+CD8+ T cells in 10 normal individuals to assess their replicative history. Overall, the telomeric lengths were found to be significantly shorter in the CD28-CD8+ T cell subset compared with the CD28+CD8+ subset. Furthermore, clonally expanded TCRBV11+CD8+ T cells from an individual exhibited telomeric lengths that were 2.9 kb shorter than those found in the polyclonal CD28+CD8+ T cell subset. These findings indicate that clonally expanded CD28-CD8+ T cells have undergone many more rounds of replication than CD28+CD8+ T cells, and consistent with the loss of CD28 expression, they may have reached a state of replicative senescence.

Oligoclonality of V beta 3 TCR chains in the CD8+ T cell population of rheumatoid arthritis patients

It has been established that oligoclonal expansion is a common feature of the CD8+ T cell population, particularly within the CD8+ CD57+ lymphocyte subset. In addition, clonal malignancies involving CD8+ CD57+ T cells (large granulocytic lymphocytic leukemias) are often accompanied by rheumatoid arthritis, Felty's syndrome, or both. Therefore, to identify disease-related alterations in the CD8+ T cell repertoire, we have compared the patterns of oligoclonality in the CD8+ T cells of rheumatoid arthritis patients (n = 32) with those of age-matched controls (n = 25). By using a multiplex PCR assay for the CDR3 length of TCR beta-chains, we have found a striking increase in the frequency of CD8+ oligoclonality involving V beta 3 TCR: 50% of the rheumatoid arthritis patients had evidence of oligoclonality in this TCR family compared with 4% of controls (p < 0.0002). In addition, two unrelated RA patients had clonally dominant CD8+ T cell beta receptors that were identical in amino acid sequence, suggesting selection by a common Ag. An analysis of a subset of RA patients with mAbs specific for V beta 3 TCR revealed the presence of clonal expansion in a minority of patients usually, but not exclusively, involving the CD57+ subset. These data define a phenotype of the T cell repertoire that is strongly associated with rheumatoid arthritis; the mechanisms and genetic and environmental factors that explain this phenomenon remain to be defined.

Oligoclonality of V beta 3 TCR chains in the CD8+ T cell population of rheumatoid arthritis patients

It has been established that oligoclonal expansion is a common feature of the CD8+ T cell population, particularly within the CD8+ CD57+ lymphocyte subset. In addition, clonal malignancies involving CD8+ CD57+ T cells (large granulocytic lymphocytic leukemias) are often accompanied by rheumatoid arthritis, Felty's syndrome, or both. Therefore, to identify disease-related alterations in the CD8+ T cell repertoire, we have compared the patterns of oligoclonality in the CD8+ T cells of rheumatoid arthritis patients (n = 32) with those of age-matched controls (n = 25). By using a multiplex PCR assay for the CDR3 length of TCR beta-chains, we have found a striking increase in the frequency of CD8+ oligoclonality involving V beta 3 TCR: 50% of the rheumatoid arthritis patients had evidence of oligoclonality in this TCR family compared with 4% of controls (p &lt; 0.0002). In addition, two unrelated RA patients had clonally dominant CD8+ T cell beta receptors that were identical in amino acid sequence, suggesting selection by a common Ag. An analysis of a subset of RA patients with mAbs specific for V beta 3 TCR revealed the presence of clonal expansion in a minority of patients usually, but not exclusively, involving the CD57+ subset. These data define a phenotype of the T cell repertoire that is strongly associated with rheumatoid arthritis; the mechanisms and genetic and environmental factors that explain this phenomenon remain to be defined.

Oligoclonality of CD8+ T cells in multiple sclerosis

We have shown earlier that CD8+ T cell oligoclonality occurs frequently in normal individuals and general exhibits a very diverse repertoire. In order to investigate the role of CD8+ T cells in MS, we analysed CD8 oligoclonality in 125 patients with MS in varying stages of disease. A multiplex PCR assay for CDR3 length variation was employed to detect oligoclonality in 25 TCRBV segments/families. CD8 clonal dominance was found to be frequent in MS. Comparison of the CD8 T cell repertoire in MS with that in normal controls revealed an increased frequency of oligoclonality involving the TCRBV9, -18 and -23 families. Sequence analysis of the TCRs from these clonally dominant CD8+ cells revealed a high degree of diversity overall. However, we observed one instance of identical TCRBV18 sequences in CD8 cells from two unrelated MS patients. In addition, several TCRs with motifs homologous to those found in MS brain and MBP specific T cell clones in EAE and MS were also detected. Future characterization of the function and specificity of these clonally expanded populations may provide insight into the nature of immune dysregulation in this autoimmune disorder.

[Cerebral metastases. Review of a hospital population]

Cerebral Metastases are diagnosed in approximately 20-30% of patients with primary tumours. Because of the improvement of central nervous system imagining technology and of the newly effective therapeutic schemes, the incidence of this particular type of cerebral lesion tends to increase. In this retrospective study the authors review the patients admitted in the Neurology, Neurosurgery and Medicine departments and in the outpatient chemotherapy consultation, with a diagnosis of cerebral metastases. Sex and age, neurologic symptoms at presentation, neuroradiologic findings, primary tumour origin, treatment outcomes and prognosis were evaluated in this population.

Oligoclonality in the human CD8+ T cell repertoire in normal subjects and monozygotic twins: implications for studies of infectious and autoimmune diseases

BACKGROUND

We have previously demonstrated CD8+ T cell clonal dominance using a PCR assay for the CDR3 length of T cell receptors belonging to a limited number of TCRBV segments/families. In this study, we have modified this approach in order to analyze more comprehensively the frequency of oligoclonality in the CD8+ T cell subset in 25 known TCRBV segments/families. In order to assess the relative roles of genes and environment in the shaping of a clonally restricted CD8+ T cell repertoire, we have analyzed clonal dominance in the CD8+ T cell population of monozygotic twins, related siblings, and adoptees.

MATERIALS AND METHODS

Oligoclonality was assessed in the CD8+ T cell subsets using a multiplex PCR approach to assay for CDR3 length variation across 25 different TCRBV segments/families. Specific criteria for oligoclonality were established, and confirmed by direct sequence analysis of the PCR products. This assay was used to investigate the CD8+ T cell repertoire of 56 normal subjects, as well as six sets of monozygotic (MZ) twins.

RESULTS

Seventy-two percent of normal subjects (n = 56) had evidence of oligoclonality in the CD8+ T cell subset, using well-defined criteria. Although MZ twins frequently displayed CD8+ T cell clonal dominance, the overall pattern of oligoclonality was very diverse within each twin pair. However, we occasionally observed dominant CD8+ T cell clones that were highly similar in sequence in both members of some twin pairs. Not a single example of such similarity was observed in normal controls or siblings.

CONCLUSIONS

Oligoclonality of circulating CD8+ T cells is a characteristic feature of the human immune system; both host genetic factors and environment shape the pattern of oligoclonality in this T cell subset. The high frequency of this phenomenon in normal subjects provides a background with which to evaluate CD8+ T cell oligoclonality in the setting of infection or autoimmune disease. Further phenotypic and functional characterization of these clonally expanded T cells should provide insight into normal immune homeostasis.

[Acute cerebrovascular accident and heart disease. Prospective study of 248 patients]

OBJECTIVE

To evaluate the heart disease associated to different type and sub-types of cerebrovascular disease with particular reference to potential cardiac sources of embolus (CPE).

DESIGN

Prospective study in 248 consecutive patients with acute stroke, admitted to a Clinical Medicine Unit in three independent time periods.

SETTING

Internal Medicine Clinic of University Hospital in Lisbon.

METHODS

Neurologic and cardiologic examination were performed and all patients were also submitted to different complementary tests, including a Computer Tomography Scan of the brain (TAC) and a Echocardiogram (ECO). We identified two types and two sub-types: intracerebral haemorrhage (HI) or ischemic stroke (AI) and among AI, cortical (C) or subcortical (SC) ischemic stroke. For each type and sub-type we evaluated past history, heart disease, hypertension (HTA), electrocardiogram, echocardiogram (ECO) and CPE.

PATIENTS

Two hundred and forty eight patients (52% were men) with mean age 68.0 +/- 10.2 years and ages between 40 and 92 years. Thirty seven (15%) died.

MAIN RESULTS

Eighty four percent were AI and among them 45% were C. Previous strokes were more prevalent in AI 29% (p < 0.01). There was heart disease in 81% and hypertensive cardiopathy was more frequent in HI 63% (p < 0.002). HTA and atrial fibrillation (FA) were more frequent in HI 83% (p < 0.05) and in AI 25% (p < 0.004) respectively. ECO showed a dilatation of left atrium more frequent in AI 28% (p < 0.05) and left ventricular concentric hypertrophy index (IHCE) in HI 50% (p < 0.05). CPE, including FA, was identified in 34% of patients, was more prevalent in AI 38% (p < 0.001) and among it FA was significantly more frequent in C 32% (p < 0.02).

CONCLUSIONS

Heart disease is very frequent in stroke. The diagnosis of this condition is very important for stroke prophylaxis and prognosis. HTA and hypertensive cardiopathy have a great prevalence and were more related to HI. CPE and FA were very frequent and their diagnosis are important for prevention of AI and specially for embolic stroke. ECO is useful to identify CPE in elderly patient in particular to characterize heart disease.

[Coronary thrombosis in patients who have died of acute myocardial infarct. A clinico-anatomical study of 167 successive cases]

AIM

To determine the incidence of recent coronary thrombus in a population died of acute myocardial infarction (AMI) and to evaluate the relation between its presence and some clinical parameters (age, gender, time interval between the onset of symptoms and death and cause of death).

POPULATION AND METHODS

167 hearts of consecutive patients died of AMI and without thrombolytic therapy. Hearts were fixed in formaldehyde 10% for two weeks and then the epicardial coronary arteries were divided in 5 mm segments, which were examined by visual inspection to identify recent thrombi. Cuts for microscopical observation were obtained in cause of doubt. In each patients a clinical protocol with 64 parameters is performed. In statistical treatment Pearson's dispersion test and Student's t test were used.

RESULTS

We found coronary thrombus in the infarction related artery in 74%. The thrombus distribution in the epicardiac coronary arteries was the following: 47% in the anterior descendent artery, 27% in the right coronary artery, 21% in the left circumflex and 5% in the left main. The comparison between the groups with and without coronary thrombus showed no differences in age and gender, but the time interval between AMI and death was shorter in the group with thrombus. Concerning the different causes of death (cardiac failure, cardiac rupture and others) the coronary thrombus prevailed in the group with left ventricule free wall rupture. There was no influence of the time interval between AMI and death on the larger prevalence of coronary thrombus found in cardiac rupture.

CONCLUSIONS

The frequency of recent coronary thrombus in the infarction related artery was of 74% in this group of patients died of AMI without thrombolytic therapy. The presence of coronary thrombus was not related with patients age or gender. The frequency of coronary thrombus was inversely proportional to the time interval between AMI and death, and larger in the group with left ventricule free wall rupture.

[Formation of left ventricular thrombus in acute myocardial infarction: significance of the determination of fibrinogen, of products of fibrinogen degradation, and of plasminogen]

OBJECTIVE

To evaluate the significance of the fibrinogen, the plasminogen and the fibrinogen degradation products levels as marks of left intraventricular thrombosis (LIVT) in acute myocardial infarction (AMI).

METHODS

219 consecutive patients of AMI admitted in a Coronary Care Unit of an University Hospital, were prospectively studied. All protocols included a clinical evaluation, an M-mode and 2D echocardiographic study and blood samples, at day 1, 3, 7 and at hospital discharge. In the intraventricular thrombus evaluation just the 4 Asinger grade was considered. In the laboratory evaluation we used: the Clauss chronometric method for the fibrinogen, the colorimetric method for the plasminogen and the agglutination in plaque for the FDP. The patients with ECO in the 2 or 3 Asinger grades and those in which ECO and laboratory study were not performed in the same day, were excluded. 101 patients remained on the study, and they were divided in two groups: 53 patients with LIVT and 48 patients without it.

RESULTS

In both groups the fibrinogen raised along the first six days of the AMI, however in the group with LIVT this level didn't raise as high as in the group without LIVT (p < 0.001). In the FDP evaluation two peaks were found, one at 48 hours and another on the 6 th day, but there were no differences between the two groups. The plasminogen values raised along the first week of AMI, in a similar way in both groups.

CONCLUSIONS

a) Fibrinogen levels raises in AMI, but this elevation is significantly smaller in the group with LIVT, which suggests fibrinogen consume in fibrin formation of the thrombus. b) FDP and plasminogen levels raise along the first week of AMI, but in a similar way in the two groups. c) None of these parameters permitted to individualize patients with thrombus formation.

[Coronary atherosclerosis in acute myocardial infarct. Anatomic profile of diverse causes of death]

OBJECTIVE

to study the degree of coronary obstruction by atherosclerotic plaques in a population dying with acute myocardial infarction. We defined subgroups by the degree of the obstructive lesion and compared the severity and distribution of coronary atherosclerotic lesions in different groups according to cause.

STUDY DESIGN

systematic prospective study in patients dying in the acute phase of myocardial infarction in a University Hospital Coronary Unit during a four years period.

POPULATION AND METHODS

we studied 193 patients corresponding 77% of the patients dead in the same period. 24 patients were excluded by technical reasons related to the preparation of necropsic material. The clinical protocol included 64 parameters and were considered the following causes of death: left ventricular failure (shock or acute pulmonary edema), left ventricular free wall rupture, interventricular septum rupture, primary asystole, pulmonary embolism and ventricular fibrillation. To study of the heart we performed the transverse slices technic after fixation; to study the epicardial coronary arteries we isolated the coronaries after fixation and made 5 mm transverse slices. The slices were macroscopic and microscopic evaluated for the degree of coronary obstruction in every 5 mm segment. We classified the degree of coronary obstruction in five grades: less than or equal to 25%; greater than 25% e less than or equal to 50%; greater than 50% e less than or equal to 75%; greater than 75% e less than 100%; and total obstruction.

RESULTS

the degree of coronary obstruction in each epicardial segment were: Right ostium--grade I = 21%, grade II = 46%, grade III = 26%, grade IV = 7%, grade V = 0; Right coronary--grade I = 5%, grade II = 10%, grade III = 19%, grade IV = 28%, grade V = 38%; Left ostium--grade I = 27%, grade II = 50%, grade III = 19%, grade IV = 4%, grade V = 0; Left main--grade I = 16%, grade II = 43%, grade III = 28%, grade IV = 10%, grade V = 2%; Anterior descendent--grade I = 1%, grade II = 5%, grade III = 11%, grade IV = 34%, grade V = 49%; Left circumflex--grade I = 2%, grade II = 14%, grade III = 22%, grade IV = 40%, grade V = 22%. The number of coronary arteries with more than 75% obstruction for each group of one, two or three vessel disease were: 1 vessel--41 cases; 2 vessels--56 cases; 3 vessels--68 cases. The number of vessels with more than 75% obstruction for each cause of death were: Wall rupture--1 vessel = 20, 2 vessels = 18, 3 vessels = 11; Septum rupture--1 vessel = 0, 2 vessels = 2, 3 vessels = 2; Shock--1 vessel = 12, 2 vessels = 21, 3 vessels = 30; Acute pulmonary edema--1 vessel = 1, 2 vessels = 9, 3 vessels = 7; Asystole--1 vessel = 4, 2 vessels = 1, 3 vessels = 8; Pulmonary embolism--1 vessel = 2, 2 vessels = 5, 3 vessels = 8; Ventricular fibrillation--1 vessel = 2, 2 vessels = 0, 3 vessels = 2.

CONCLUSION

in most patients dying with acute myocardial infarction, the coronary atherosclerotic lesions were present in two or three epicardial coronary arteries. The left anterior descendent artery was the more frequent artery with major lesion (greater than 75%). Major atherosclerotic lesion in just one vessel were more frequent in patients dying by cardiac rupture.