Hepatitis C virus is detected in a monocyte/macrophage subpopulation of peripheral blood mononuclear cells of infected patients.

Hepatitis C virus (HCV) is the primary agent of posttransfusion non-A, non-B hepatitis. HCV RNA was detected in peripheral blood mononuclear cells (PBMC) by polymerase chain reaction in 17 of 24 HCV-infected patients with chronic hepatitis with or without cirrhosis. One of 5 patients whose PBMC contained HCV RNA also had negative-stranded HCV RNA in the PBMC. In 3 of 11 patients whose PBMC contained HCV RNA, flow cytometry with a murine monoclonal antibody to HCV core epitope revealed cytoplasmic staining of peripheral blood monocytes. The monocyte surface and the peripheral blood lymphocytes did not stain for HCV core epitopes. No correlation could be made between the presence of HCV RNA or antigen in PBMC and any serologic markers of HCV infection. These results indicate that monocyte uptake of HCV by either phagocytosis or infection may be part of the pathophysiology of this chronic disease.     

T cell numbers relate to bone involvement in Gaucher disease.

The major elements of bone pathology in Gaucher disease are a failure of osteoclast and osteoblast function, resulting in osteopenia and also osteonecrosis. T lymphocytes have recently been found to be involved in the regulation of osteoblast/osteoclast activity in vitro. In the present report the peripheral blood T major lymphocyte subsets were investigated in a group of genotyped type 1 Gaucher disease patients. A total of 31 patients were studied: 21 non-splenectomized (5 N370S homozygotes) and 10 splenectomized (of whom 1 was a N370S homozygote). The results show that non-splenectomized patients present a decrease in absolute numbers of peripheral blood T lymphocytes, specially the CD4+ T subset. However, when patients were analyzed with respect to the presence of bone disease, the number of CD8+ T lymphocytes was found to be statistically significantly lower in patients presenting bone involvement. Furthermore, lower numbers of CD8+ T lymphocytes were significantly correlated with higher levels of plasma tartrate resistant acid phosphatase (TRAP) activity, a putative marker of osteoclast cell activity. These in vivo findings are in agreement with the results reached in vitro by others. They provide an additional marker of disease severity in Gaucher disease. In the group of genotyped Gaucher disease patients, the majority of the N370S homozygous patients presented a clinically milder phenotype, including the absence of bone involvement, confirming earlier reports predicting that a number of these patients may remain undiagnosed. Collectively the homozygosity for the N370S mutation and normal T cell numbers may provide additional markers for the clinical heterogeneity of Gaucher disease.     

Peripheral blood T lymphocytes from patients with early rheumatoid arthritis express RANKL and interleukin-15 on the cell surface and promote osteoclastogenesis in autologous monocytes

OBJECTIVE: To investigate the osteoclastogenic potential of T cells from the peripheral blood (PB) and synovial fluid (SF) of patients with rheumatoid arthritis (RA) on autologous monocytes, and to study the cytokines implicated in this process. METHODS: T cells and monocytes were isolated from the PB of 20 healthy subjects and 20 patients with early RA, and from the SF of 20 patients with established RA. Autologous T cell/monocyte cocultures were established in the absence of exogenous cytokines or growth factors in order to examine spontaneous ex vivo osteoclast differentiation by tartrate-resistant acid phosphatase staining and calcified matrix resorption activity. RESULTS: Surface RANKL was expressed on freshly isolated T cells from the PB of patients with early RA and the SF of patients with established RA. In addition, surface interleukin-15 (IL-15) was detected on freshly isolated T cells and monocytes from the PB of patients with early RA and the SF of patients with established RA. Autologous T cell/monocyte cocultures derived from the SF of patients with established RA and from the PB of patients with early RA, but not from the PB of healthy controls, resulted in osteoclast differentiation that was significantly inhibited by osteoprotegerin (OPG) and by neutralizing monoclonal antibodies to IL-15, IL-17, tumor necrosis factor alpha (TNFalpha), and IL-1beta. OPG, anti-TNFalpha, and anti-IL-1beta demonstrated a cooperative inhibitory effect. At 1-year followup, surface RANKL and IL-15 and ex vivo osteoclastogenesis were no longer observed on PB T cells or monocytes from patients with early RA in whom clinical remission had been achieved with treatment. CONCLUSION: T cells are important contributors to the pathogenesis of bone erosions in RA through interaction with osteoclast precursors of the monocyte/macrophage lineage.     

Predictors of osteoclast activity in patients with sickle cell disease

Background

Bone changes are common in sickle cell disease, but the pathogenesis is not fully understood. Tartrate-resistant acid phosphatase (TRACP) type 5b is produced by bone-resorbing osteoclasts. In other forms of hemolytic anemia, increased iron stores are associated with osteoporosis. We hypothesized that transfusional iron overload would be associated with increased osteoclast activity in patients with sickle cell disease.

Design and Methods

We examined tartrate-resistant acid phosphatase 5b concentrations in patients with sickle cell disease and normal controls of similar age and sex distribution at steady state. Serum tartrate-resistant acid phosphatase 5b concentration was measured using an immunocapture enzyme assay and plasma concentrations of other cytokines were assayed using the Bio-Plex suspension array system. Tricuspid regurgitation velocity, an indirect measure of systolic pulmonary artery pressure, was determined by echocardiography.

Results

Tartrate-resistant acid phosphatase 5b concentrations were higher in 58 adults with sickle cell disease than in 22 controls (medians of 4.4 versus 2.4 U/L, respectively; P=0.0001). Among the patients with sickle cell disease, tartrate-resistant acid phosphatase 5b independently correlated with blood urea nitrogen (standardized beta=0.40, P=0.003), interleukin-8 (standardized beta=0.30, P=0.020), and chemokine C-C motif ligand 5 (standardized beta=−0.28, P=0.031) concentrations, but not with serum ferritin concentration. Frequent blood transfusions (>10 units in life time) were not associated with higher tartrate-resistant acid phosphatase 5b levels in multivariate analysis. There were strong correlations among tartrate-resistant acid phosphatase 5b, alkaline phosphatase and tricuspid regurgitation velocity (r>0.35, P<0.001).

Conclusions

Patients with sickle cell disease have increased osteoclast activity as reflected by serum tartrate-resistant acid phosphatase 5b concentrations. Our results may support a potential role of inflammation rather than increased iron stores in stimulating osteoclast activity in sickle cell disease. The positive relationships among tartrate-resistant acid phosphatase 5b, alkaline phosphatase and tricuspid regurgitation velocity raise the possibility of a common pathway in the pulmonary and bone complications of sickle cell disease.     

Hairy cell leukaemia presenting with ascites, pleural effusion and increased CA 125 serum level

The body cavities are rarely involved in hairy cell leukaemia. Here we report a patient who had pancytopenia, hepatosplenomegaly, massive haemorrhagic ascites, pleural effusion at the left hemithorax and increased CA 125 serum level at the time of initial diagnosis. Laparoscopy showed multiple nodular white, opaque lesions on the omentum and on the parietal peritoneum. Laparoscopic biopsy of these lesions, and a bone marrow biopsy revealed a diffuse cellular infiltrate of tartrate-resistant acid phosphatase staining mononuclear cells. These mononuclear cells with irregular cytoplasmic protrusions were also found in the peripheral blood, in the ascites fluid and in the pleural effusion. The patient was treated with cladribine 0.1 mg/kg/day with continuous infusion for seven days. Three months after the treatment, the patient achieved a complete remission with normalisation of the peripheral blood count, bone marrow findings, CA 125 serum level, with no detectable ascites and/or pleural effusion.     

Clinical differential diagnosis of hairy-cell leukaemia

The data on hairy-cell leukaemia (HCL) and resembling disorders in the literature and in our patients were analyzed to determine which clinical features and laboratory data are important for the recognition of HCL in an early stage. In pancytopenic patients the typical pattern of bone marrow involvement in HCL and the low number of monocytes in the peripheral blood appear to be essential for the differential diagnosis. In patients with many neoplastic cells in the peripheral blood, the presence of neutropenia and monocytopenia as well as tartrate-resistant acid phosphatase activity in the neoplastic cells, appears to be crucial for early diagnosis. Thus, the clinical features and routine laboratory data alone are sufficient in the majority of cases to suggest the diagnosis HCL. The monocytopenia proved to be most helpful in this respect. Nevertheless, in all patients, and certainly in patients presenting with atypical features, a bone marrow biopsy is indispensable for the correct diagnosis.     

Preactivated peripheral blood monocytes in patients with essential hypertension.

The purpose of this study was to investigate the possible involvement of human peripheral blood monocytes in the pathology of hypertensive disease. We determined the in vitro secretion patterns of proinflammatory cytokines obtained from isolated peripheral monocytes from normal controls and from hypertensive patients either after in vitro stimulation with angiotensin II (Ang II) with or without preincubation with an Ang II type 1 receptor antagonist (losartan) or after stimulation with lipopolysaccharide. Blood samples were obtained from 22 patients with essential hypertension (before any drug administration or after interruption of antihypertensive therapy) and from 24 normotensive healthy individuals used as a control group. Peripheral blood monocytes were isolated by density gradient centrifugation and plastic adherence. The state of monocyte activity was determined by the capacity to secrete tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6, (IL-6) either spontaneously or after stimulation. Cytokine concentrations were determined in culture supernatants by specific ELISA. Proinflammatory cytokine levels were assessed by semiquantitative reverse transcribed polymerase chain reaction. After stimulation with Ang II, the IL-1beta secretion of peripheral blood monocytes was significantly increased in hypertensive patients versus healthy individuals (P<0.05). In contrast, in monocytes preincubated with losartan before exposure to Ang II, IL-1beta secretion was diminished in both groups to comparable levels. The secretion of IL-1beta and TNF-alpha was significantly increased in peripheral blood monocytes from hypertensive patients versus healthy individuals after stimulation with lipopolysaccharide (TNF-alpha, P<0.02; IL-1beta, P<0.05). Upregulation of IL-1beta and TNF-alpha secretion in peripheral blood monocytes from hypertensive patients was also seen at the RNA level. Our results indicate preactivated peripheral blood monocytes in hypertensive patients. Ang II may be directly involved in the process of monocyte activation.     

Monocyte dysfunction in patients with Gaucher disease: evidence for interference of glucocerebroside with superoxide generation [see comments]

Gaucher disease patients are occasionally affected by chronic or fulminant infections. Since Gaucher cells originate from tissue phagocytes, we studied the functional implications of glucocerbroside accumulation on phagocytes in Gaucher disease patients. Circulating monocytes and granulocytes from nine type I Gaucher disease patients, and matched controls, were studied. Evaluation of phagocytic activity included (1) maximal superoxide generation rates following stimulation by phorbol 12-myristate 13-acetate (PMA), opsonized zymosan (OZ), or formyl-methionyl-leucylphenylalanine (FMLP); (2) nitroblue tetrazolium reduction test (NBT); (3) chemotaxis toward FMLP; (4) phagocytosis of OZ particles; and (5) killing activity against Staphylococcus aureus. Superoxide generation in monocytes following PMA, OZ, and FMLP stimulation was significantly suppressed at 52% +/- 15%, 39% +/- 8%, and 51% +/- 11% of control, respectively. Superoxide generation in granulocytes was normal. NBT reduction, staphylococcal killing, and phagocytosis were also markedly decreased in monocytes, and normal in granulocytes. Mean chemotaxis rates were normal in both monocytes and granulocytes; however, decreased chemotactic rates were observed in some patients. The abnormality of superoxide generation could be reproduced in a dose- and time-dependent manner in normal circulating monocytes incubated with glucocerebroside. Superoxide generation in glucocerebroside-conditioned normal monocytes in a cell-free system showed normal superoxide generation, reflecting the integrity of the NADPH oxidase complex itself. These results demonstrate markedly compromised phagocytic functions in circulating monocytes in Gaucher disease patients. These abnormalities can be attributed to accumulation of glucocerebroside, since it could be reproduced in normal monocytes incubated with glucocerebroside. Similar abnormalities in Gaucher cells throughout the reticuloendothelial system could impair host defense, and may be of particular importance in the pathogenesis of osteomyelitis in Gaucher disease patients.     

Increased expression of monocyte CD44v6 correlates with the deveopment of encephalitis in rhesus macaques infected with simian immunodeficiency virus

In people infected with human immunodeficiency virus type 1 (HIV-1), the accumulation of macrophages in the brain correlates with encephalitis and dementia. We hypothesized that a pattern of surface marker expression in blood monocytes may serve as a marker for central nervous system (CNS) disease. Using the simian immunodeficiency virus (SIV)-rhesus monkey model, we analyzed functionally relevant surface markers on monocytes and macrophages from the blood and brain in animals that did or did not develop SIV encephalitis. At necropsy, multiple markers (CD44v6, CCR2, and CCR5 on blood monocytes and brain microglia and/or macrophages, and CX3CR1 on blood monocytes) allowed us to distinguish animals with encephalitis from those without. Furthermore, the level of expression of CD44v6 on the 2 main populations of blood monocytes--those that express either low or high levels of CD16--was significantly increased in animals with encephalitis. A longitudinal analysis of blood monocyte markers revealed that as early as 28 days after inoculation, CD44v6 staining could distinguish the 2 groups. This provides a potential peripheral biomarker to identify individuals who may develop the HIV-induced CNS disease. Furthermore, given its role in cellular adhesion and as an osteopontin receptor, CD44v6 upregulation on monocytes offers functional clues to the pathogenesis of such complications, and provides a target for preventative and therapeutic measures.     

Monocyte-mediated inhibition of lymphocyte blastogenesis in Hodgkin disease

Mononuclear leukocytes isloated from the blood of previously treated patients with advanced active Hodgkin disease contained high concentrations of monocytes and showed poor lymphocyte blastogenesis to mitogens. In five of eight patients with disseminated disease, blastogenesis became normal or improved markedly when the leukocyte suspensions were depleted of monocytes before culture. Addition of autologous macrophages to the monocyte-depleted lymphocytes resulted in a reappearance of the inhibition of blastogenesis. Monocyte inhibition was associated with the presence of active disease, lymphocytopenia, and low lymphocyte/monocyte ratios in the peripheral blood. The role of previous treatment is uncertain, since inhibition tended to disappear when the patients were retreated. Inhibitory monocyte-lymphocyte interactions may be one of the causes of impaired cell-mediated immunity in Hodgkin disease.     

In vitro method for the screening and monitoring of estrogen-deficiency osteoporosis by targeting peripheral circulating monocytes

Bone loss occurs insidiously and initially asymptomatically; therefore, osteoporosis is frequently diagnosed only after the first clinical fracture. The aim of this study was to test the hypothesis is that by simply observing the behavior of cultured peripheral monocytes, it might be possible to diagnose altered bone remodeling and, therefore, limit the complications associated with osteoporosis, especially fractures. Monocytes isolated as mononuclear precursors from healthy and ovariectomized rats were cultured both in basal and differentiation medium for up to 3 weeks. Viability and differentiation capability towards the osteoclastic phenotype was checked by light microscopy at early times, whereas differentiation state and synthetic activity (tartrate-resistant acid phosphatase (TRAP) staining; phalloidin, fluorescin isothiocynate (FITC) staining, cathepsin K, metalloproteinase 7 and 9, MMP-7 and MMP-9) were measured at 1, 2, and 3 weeks. Compared to their controls, monocytes isolated from ovariectomized rats proliferate and lean toward the osteoclastic phenotype in the absence of differentiating factors. In both culture conditions, osteoclasts from ovariectomized rats showed significantly higher productions of cathepsin K, MMP-7, and MMP-9 than those of cells isolated from healthy rats, steadily over time. These results obtained in an animal osteoporotic model, if confirmed by clinical studies, open up the possibility to assess the presence of an alteration in bone remodeling with a simple in vitro diagnostic test requiring a small blood sample and less than 48 h. This might allow to early select patients with a spontaneous viability and differentiation of monocytes to osteoclasts for further diagnostic techniques.     

A fragment of alpha-actinin promotes monocyte/macrophage maturation in vitro

Conditioned media (CM) from cultures of HL-60 myeloid leukemia cells grown on extracellular bone marrow matrix contains a factor that induces macrophage-like maturation of HL-60 cells. This factor was purified from the CM of HL-60 cells grown on bone marrow stroma by ammonium sulfate precipitation, then sequential chromatography on DEAE, affi-gel blue affinity, gel exclusion, and wheat germ affinity columns, followed by C-4 reverse phase HPLC, and SDS-PAGE. The maturation promoting activity of the CM was identified in a single 31 kD protein. Amino acid sequence analysis of four internal tryptic peptides of this protein confirmed significant homology with amino acid residues 48-60, 138-147, 215-220, and 221-236 of human cytoskeletal alpha-actinin. An immunoaffinity purified rabbit polyclonal anti-chicken alpha-actinin inhibited the activity of HL-60 conditioned media. A 27 kD amino-terminal fragment of alpha-actinin produced by thermolysin digestion of chicken gizzard alpha-actinin, but not intact alpha-actinin, had maturation promoting activity on several cell types, including blood monocytes, as measured by lysozyme secretion and tartrate-resistant acid phosphatase staining. We conclude that an extracellular alpha-actinin fragment can promote monocyte/macrophage maturation. This represents the first example of a fragment of a cytoskeletal component, which may be released during tissue remodeling and repair, playing a role in phagocyte maturation.     

Dendritic cells in patients with type I Gaucher disease are decreased in number but functionally normal

Gaucher disease is a lysosomal storage disorder, in which undigested glucosylceramide is deposited in the cytoplasm of mature macrophages, which accumulate in the bone marrow and the reticuloendothelial system. Dendritic cells are bone marrow-derived cells, specialized for the uptake, processing, transport and presentation of antigens to T-lymphocytes. We investigated peripheral blood dendritic cell-precursors, as well as the potential of peripheral blood monocytes and bone marrow-derived progenitor cells, to differentiate into mature dendritic cells in 12 patients with type I Gaucher disease. Results of the 10 adult patients were compared with those of 10 healthy volunteers, matched for age and sex. Six patients were anemic and 9 were thrombocytopenic, but none had severe bone disease. Both myeloid and plasmacytoid dendritic cells of patients with Gaucher disease, as well as the yield of the monocyte-derived dendritic cells, obtained after GM-CSF and IL-4 stimulation, were found significantly decreased, when compared to controls (myeloid dendritic cells: 0.19 +/- 0.07% vs. 0.34 +/- 0.10%, P = 0.009, plasmacytoid dendritic cells: 0.17 +/- 0.12% vs. 0.39 +/- 0.13%, P = 0.004, monocyte-derived dendritic cells: 4.8 +/- 3.5% vs. 8.3 +/- 3.2%, P = 0.036). However, the immunophenotypic profile of dendritic cells, estimated by CD1a, CD40, CD54, CD80, CD83 and HLA-DR expression, the endocytic and allo-stimulatory capacity of the immature, as well as of the TNF-alpha- or lipopolysaccharite-stimulated mature monocyte-derived dendritic cells, was similar to those obtained by healthy controls. In addition, bone marrow-derived CD34+ cells differentiated in the presence of GM-CSF, SCF, TNF-alpha and IL-4 into mature dendritic cells that did not differ in number, phenotype and allo-stimulatory activity from those of controls. Our findings suggest that patients with Gaucher disease exhibit mainly quantitative defects of their dendritic cells' system, demonstrated by decreased circulating dendritic cell precursors of both myeloid and plasmacytoid type. This finding may contribute to the poor immune response against infectious agents and an impaired immune surveillance, associated with an increased risk of developing a neoplastic disease.     

Hairy cell leukemia expressing SIgM+, SIgG-, CD11b+ and CD21+ and accompanying lymphadenopathy without splenomegaly]

Hairy cell leukemia (HCL) expressing both surface monocytoid antigen and IgM (kappa) was reported. A 62-year-old male was admitted to our hospital in September 21, 1989 because of leukocytosis. Physical examinations showed axillary and inguinal lymphadenopathy but no hepato-splenomegaly. The leukocyte count was 12,600/microliters with 73% of abnormal cells like large lymphocytes which had abundant cytoplasm and hairy appearance under phase microscopy. They had ruffles with microvilli under electron microscope. Bone marrow puncture showed normocellular marrow with 71.2% of abnormal cells similar to the peripheral blood. Surface markers were CD11b+, CD21+, HLA-DR+, Tac- and IgM (kappa). They were positive for ++acid phosphatase staining, but negative for peroxidase and tartrate-resistant acid phosphatase staining. He was diagnosed as Japanese type HCL. HCL expressing both surface monocytoid antigen and IgM is rare and the clinical features of our case are compared with those reported in Japan.     

Plasma chitotriosidase and CCL18: Early biochemical surrogate markers in type B Niemann-Pick disease

Summary Type B Niemann-Pick disease (NPD) is a nonneuronopathic lysosomal storage disorder which is characterized by accumulation of sphingomyelin-laden macrophages. The availability of plasma markers for storage cells may be of great value in facilitating therapeutic decisions. Given the similarity of the storage cells in NPD and Gaucher disease, we studied Gaucher plasma markers (chitotriosidase and CCL18) in two siblings homozygous for the R228C mutation in acid sphingomyelinase (ASM) and a type B course of NPD. The older sibling, first examined at the age of 9 months, showed marked hepatosplenomegaly and pulmonary involvement. The younger sibling has mild asymptomatic hepatosplenomgaly at the age of 5 months. Analysis of plasma specimens revealed markedly increased levels of chitotriosidase and CCL18 in the older sibling. In the younger child also, plasma chitotriosidase and CCL18 were clearly elevated above normal values almost immediately after birth and rapidly increased further. Histochemistry confirmed production of CCL18 by foam cells. In conclusion, plasma chitotriosidase and CCL18 may also serve as markers for the formation of pathological lipid-laden macrophages in type B NPD, in analogy to Gaucher disease. The availability of sensitive plasma surrogate markers may be of great value for monitoring the efficacy of enzyme supplementation therapy that is currently being developed.     

Improvement of Splenomegaly and Pancytopenia by Enzyme Replacement Therapy Against Type 1 Gaucher Disease: A Report of Sibling Cases

Gaucher disease is a genetic lipid storage disease and represents a potentially serious health problem. It arises from a deficiency of glucocerebrosidase activity with secondary accumulation of large quantities of glucocerebroside. Symptoms are usually multisystemic, often debilitating or disabling, and sometimes disfiguring, and they can lead to death. We report objective clinical response's to repeated infusion of human placental and recombinant glucocerebrosidase in 2 patients with type 1 Gaucher disease and increased hemoglobin levels and platelet counts. Splenic volume decreased during the period of enzyme administration. Enzyme replacement therapy has improved the treatment of type 1 Gaucher disease by safely and effectively arresting, decreasing, or normalizing many of its major signs and symptoms. Consideration by physicians must be given to Gaucher disease, and appropriate treatments must be given when confronted with cryptogenic pancytopenia or hepatosplenomegaly.     

The function in vitro of macrophages from the intestinal mucosa of patients with Crohn's disease: An association between chemotactic migration and granulomata

The chemotactic migration in vitro of intestinal macrophages and peripheral blood monocytes has been assessed in patients with Crohn's disease, ulcerative colitis, and miscellaneous intestinal diseases. In all groups, the chemotaxis of peripheral blood monocytes was similar to that of healthy subjects. Intestinal macrophages migrated similarly to autologous monocytes in patients with ulcerative colitis and in the miscellaneous group. In contrast, intestinal macrophages from patients with Crohn's disease exhibited a wide range of chemotaxis from markedly suppressed to normal. This variation was independent of drug treatment and the degree of inflammation present. However, patients in whom granulomata were not present exhibited a significant depression of chemotaxis compared with those with granulomata, with disease controls (ulcerative colitis patients), and with the miscellaneous group. Such a difference was not reflected in monocytes from autologous peripheral blood. These findings indicate the presence of local mucosal suppressive factors in some patients with Crohn's disease and could suggest that the diminished ability of macrophages to accumulate in a focus of inflammation may be an underlying mechanism for the failure to form granulomata in these patients.     

Telomere length analysis in monocytes and lymphocytes from patients with systemic lupus erythematosus using multi-color flow-FISH

In order to analyse telomere length in subsets of human peripheral blood lymphocytes and monocytes, we modified a recently developed multicolor flow- fluorescent in situ hybridization (FISH) methodology that combines flow-FISH and antibody staining for cell surface antigens. We analysed telomere length of peripheral blood mononuclear cells in a group of 22 patients with systemic lupus erythematosus (SLE) and 20 age-matched healthy donors. We found that neither CD4+, CD8+, CD19+ cells nor CD14+ monocytes have significantly shorter telomeres compared with their healthy counterparts. On the basis of these findings, we then used monocyte telomere length as internal reference in order to control for intra-individual variability in telomere length. By using this approach, we could demonstrate significant telomere shortening in all three lymphocyte subsets (in all cases P < 0.05) compared with monocytes. However, these differences did not vary significantly between SLE patients and controls. In summary, telomere lengths in subpopulations of hematopoietic cells can be monitored in patients with SLE using multicolor flow-FISH. While confirming data by other groups on telomere length in lymphocyte subpopulations, our data argue against an increased proliferation rate of peripheral blood monocytes reflected by accelerated telomere shortening in patients with SLE.     

Multiple forms of acid phosphatase activity in Gaucher's disease.

Although the primary genetic defect in all individuals with Gaucher's disease is a deficiency in glucocerebrosidase activity, the finding of marked elevations in splenic and serum acid phosphatase activity is almost as consistent a finding. Gaucher spleen and serum contain at least two forms of acid phosphatase that can be readily separated by chromatography on columns containing the cation exchange resin Sulphopropyl Sephadex. The major species of acid phosphatase (designated SP-I) contained in Triton X-100 (1% v/v) extracts of Gaucher spleen accounts for 65%--95% of the total activity and has the following properties: (1) it does not bind to the cation exchange column; (2) it exhibitis a pH optimum of 4.5--5.0; (3) it is inhibited by sodium fluoride (15 mM), L(+)-tartaric acid (20 mM), and beta-mercaptoethanol (2.1 M), and (4) it is resistant to inhibition by sodium dithionite (10 mM). The minor acid phosphatase activity (designated SP-II) present in extracts of Gaucher spleen has properties similar to those of the major species of acid phosphatase activity contained in serum from patients with Gaucher's disease: (1) it binds firmly to cation exchange columns (eluted by 0.5 M sodium chloride); (2) it exhibits a pH optimum of 5.0--6.0; (3) it is inhibited by sodium fluoride and sodium dithionite; and (4) it is resistant to inhibition by beta-mercaptoethanol (2.1 M) and L(+)-tartaric acid (20 mM). In addition, a second form of acid phosphatase that is tartrate resistant was found to be elevated in Gaucher serum. This form of serum acid phosphatase did not bind to Sulphopropyl Sephadex, was found to be significantly resistant to beta-mercaptoethanol (2.1 M), and was only partially inhibited by sodium dithionite (10 mM). The findings reported here indicate that at least three distinct forms of acid phosphatase activity are elevated in Gaucher's disease. Furthermore, the minor acid phosphatase activity contained in spleen homogenates has properties very similar to those of the major acid phosphatase activity observed to be present in serum of patients with Gaucher's disease. These data indicate that simple spleen spillage cannot account for the increased levels of serum acid phosphatase in patients with Gaucher's disease.     

Human immunodeficiency virus type 1 strains in the lungs of infected individuals evolve independently from those in peripheral blood and are highly conserved in the C-terminal region of the envelope V3 loop.

To determine whether human immunodeficiency virus type 1 (HIV-1) strains in the lungs of infected individuals are derived from proviral forms contemporaneously present in the peripheral blood or whether they evolve independently as an autonomous pool of viral quasispecies, HIV-1 envelope V3 domain structures at these sites were analyzed and compared. The V3 loop proviral nucleotide and inferred amino acid sequences from lung bronchoalveolar lavage, where HIV-1 is primarily found in macrophages, were more homogeneous within individuals than those from unseparated peripheral blood mononuclear cells, where virus is predominantly in T cells. Comparison between individuals revealed that strains from bronchoalveolar lavage, but not from peripheral blood mononuclear cells, contained V3 domain nucleotide sequences with a great degree of homogeneity in the C-terminal region and a highly conserved, negatively charged amino acid motif. This V3 loop C-terminal structure could be important in the ability of HIV-1 to infect alveolar macrophages. Phylogenetic analyses of V3 domain nucleotide sequences in cells of monocyte/macrophage lineage at both sites revealed the strains in lung macrophages to have evolved further from a presumed ancestral species than those in blood monocytes and to differ considerably in the inferred V3 loop amino acid structures. These results show that, as disease progression occurs, viral strains in monocyte/macrophage lineage cells within the lung and blood microenvironments are not in a state of unrestricted bidirectional traffic but, instead, evolve independently.