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Biomedical subjects

H B Berntzen

Publications and source records attributed to H B Berntzen.

12 recordsLinked to original sources

Calprotectin in patients with systemic lupus erythematosus: relation to clinical and laboratory parameters of disease activity.

Calprotectin (L1) is a granulocyte and monocyte cytosolic protein released during activation of these cells. The plasma level of L1 has been shown to be a good marker of disease activity in rheumatoid arthritis. In this cross-sectional study of 100 patients with systemic lupus erythematosus (SLE), the serum level of L1 was found to be higher in patients than in matched controls (3661 micrograms/l versus 1051 micrograms/l; P < 0.001). The serum level of L1 was the only laboratory parameter with significant association to the disease activity index SLEDAI (r = 0.28; P < 0.01). Furthermore, the serum level of L1 was significantly higher in SLE patients with anti-DNA antibodies compared to patients without anti-DNA antibodies (4501 micrograms/l versus 3279 micrograms/l; P = 0.01). SLE patients with arthritis had higher serum levels of L1 than patients without arthritis (7652 micrograms/l versus 2811 micrograms/l; P < 0.01), indicating that the serum level of L1 also reflects arthritis activity in SLE.

Adult↗

Levels of calprotectin (leukocyte L1 protein) during apheresis.

The plasma concentration of calprotectin was measured before, during and after apheresis in patients with Guillain-Barré Syndrome (GBS), Waldenstrøm's syndrome or hypercholesterolaemia and in healthy donors of platelets. Increased calprotectin levels were found after plasma exchange in the Waldenstrøm's syndrome patients, probably caused by release of the protein from activated leukocytes. The decreased calprotectin values observed in the other patients, may be due to plasma dilution. Unexpectedly, the GBS patients were found to have high initial calprotectin levels in plasma but not in cerebrospinal fluid. In donors, normal and unchanged calprotectin concentrations were found throughout.

Blood Component Removal↗

Calprotectin in patients with rheumatoid arthritis: relation to clinical and laboratory variables of disease activity.

Calprotectin (L1) is a major granulocyte and monocyte protein which is released during activation of these cells. The plasma level of L1 is thought to reflect disease activity in rheumatoid arthritis (RA). In our cross sectional study of 70 patients with RA, L1 had significant correlations with erythrocyte sedimentation rate (r = 0.50), C-reactive protein (r = 0.58), orosomucoid (r = 0.62), platelet count (r = 0.42), leukocyte count (r = 0.33) and IgM rheumatoid factor (r = 0.32); and with the following clinical variables: number of swollen joints (r = 0.24), grip strength (r = -0.22), PIP joint circumferences (r = 0.33) and a combined global assessment score (r = 0.24). L1 was higher in seropositive (median 14,861 micrograms/l) than seronegative patients (median 10,487 micrograms/l) (p less than 0.03).

Adolescent↗

C3 activation products, C3 containing immune complexes, the terminal complement complex and native C9 in patients with rheumatoid arthritis.

Complement activation products, C9 and C3-containing circulating immune complexes (CIC), were evaluated in plasma and synovial fluid (SF) from patients with rheumatoid arthritis (RA) and osteoarthritis. C3 activation products and the fluid phase terminal complement complex were considerably elevated in SF from RA patients reaching levels five- to eighttimes that in plasma, consistant with a local activation of the whole cascade in the joints. The results emphazise the importance of detecting C3 activation by neoepitope expression instead of single fragment determinations. The concentration of native C9 was lower in synovial fluid compared with plasma, consistant with the excessive local complement activation. Increased CIC levels which correlated with the degree of complement activation were also found in the SF from the RA patients.

Adult↗

The leukocyte protein L1 in plasma and synovial fluid from patients with rheumatoid arthritis and osteoarthritis.

L1 is a major granulocyte and monocyte protein, released during activation and turnover of such cells. Blood and synovial fluid (SF) from 41 patients with rheumatoid arthritis (RA) and 6 patients with osteoarthritis (OA), were analyzed for L1 and the acute phase proteins C-reactive protein, orosomucoid, haptoglobin, alpha 1-antitrypsin and albumin as well as for differential leukocyte count. L1 levels in plasma and SF showed highly significant differences (p less than 0.0001), between the RA and OA patients. All the OA patients had normal plasma concentrations of L1 and low concentrations of L1 in SF. All the RA patients had elevated plasma levels of L1 and high L1 concentrations in SF. In the RA patients, the ratios between the protein concentrations in SF and blood were 3.29 for L1 and less than or equal to 0.64 for the acute phase proteins. In the SF, the L1 levels did not correlate with the monocyte count, while a low, positive correlation was found between L1 and the granulocyte count. The high L1 concentrations observed in SF from RA patients probably reflected an increased turnover of leukocytes in the inflamed joints. In SF from RA patients, high L1 concentrations were found in joints with a high amount of swelling. The present study suggests that L1 may represent a marker of both local and systemic inflammation.

Acute-Phase Proteins↗

The L1 protein as a new indicator of inflammatory activity in patients with juvenile rheumatoid arthritis.

L1 is a major granulocyte and monocyte protein with Mr 36.5 kDa. It is released during leukocyte activation and detected in plasma by use of an enzyme immunoassay. In our study, L1, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), orosomucoid and haptoglobin were analyzed in 127 patients with juvenile rheumatoid arthritis (79 pauci, 33 poly and 15 systemic). L1, ESR and the acute phase proteins were all found to have positive correlations with the clinical joint assessments, with L1 having the strongest correlations. High correlation coefficients were found between L1 and orosomucoid (r = 0.83), ESR (r = 0.72), haptoglobin (r = 0.71) and CRP (r = 0.65), with p less than 0.001 for all the correlations.

Antigens, Surface↗

L1, a major granulocyte protein; isolation of high quantities of its subunits.

L1 is a major granulocyte and monocyte protein with a Mr of 36.5 kDa. It is found mainly in the cytosol of these cells. Purified L1 is shown, on two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), to contain three subunits. In this study, 6 mol/l concentration of urea was found to be sufficient for disassembly of the polypeptides, and urea-containing preparative isoelectric focusing gel was used for separation of high quantities of the subunits. The pI of the eluted subunits were 5.8, 6.1 and 7.1. When tested on 2D-PAGE, the isolated subunits were found at their typical locations. Polyclonal rabbit antibodies were produced against the subunits, and the antisera were, on dot-blot, found to react with the different subunits as well as the purified L1.

Antigens, Surface↗

A longitudinal study of the leukocyte protein L1 as an indicator of disease activity in patients with rheumatoid arthritis.

L1 is a major granulocyte and monocyte protein. It is released during leukocyte activation, and the plasma level is thought to reflect the inflammatory activity. Fifteen patients with classical or definite rheumatoid arthritis were examined monthly during one year. The laboratory tests included L1, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), orosomucoid, haptoglobin, ceruloplasmin, alpha 1-antitrypsin, immunoglobulins and blood cell counts. The clinical tests included articular index, grip strength, morning stiffness and pain. The L1 protein was found to have highly significant correlations (p less than 0.0001) with orosomucoid (r = 0.86), CRP (r = 0.79), ESR (r = 0.78), haptoglobin (r = 0.75), alpha 1-antitrypsin (r = 0.63) and ceruloplasmin (r = 0.44). Significant correlation was also found between L1 and IgA. None of the laboratory variables showed significant correlation with pain, but when they were correlated with articular index, grip strength and morning stiffness, L1 was found to have the highest average correlation coefficient (p less than 0.0001).

Adult↗

The major leukocyte protein L1 as an indicator of inflammatory joint disease.

L1 is a major protein in granulocytes and monocytes. It is released during activation of these cells, and the plasma level of L1 is therefore thought to reflect the turnover of leukocytes. Peripheral blood from 96 patients hospitalized in a rheumatological department, was analysed for L1, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The total patient material was divided into groups depending on diagnosis: 47 patients with rheumatoid arthritis, 27 patients with arthritis of different etiologies, 15 patients with non-inflammatory diseases and 7 patients with arteritis. Correlation analysis were made between the different laboratory parameters. A high positive correlation was found between L1 and CRP in all the groups, and with a correlation coefficient of the total patient material of 0.68 (p less than 0.001). The correlation coefficient between L1 and ESR was 0.54 (p less than 0.001) in the total patient material, and between CRP and ESR it was 0.66 (p less than 0.001). The results indicate that the L1 protein could be a new laboratory marker of inflammation in rheumatic diseases.

Antigens, Surface↗

L1, a major granulocyte protein: antigenic properties of its subunits.

L1, a major granulocyte protein, was purified and analysed by use of two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Three subunits were visualized, and they were found to have molecular weights of 12.5 kDa, 13.3 kDa and 8.3 kDa. They were extracted from 2D-gels, and different combinations of subunits and two L1 antisera were analysed by immunodiffusion in agarose gel. The 8.3 kDa polypeptide in combination with one or both of the other polypeptides, gave immunoprecipitation with one of the L1 antisera, while no precipitation occurred when the three polypeptides were tested separately. Neither was there any precipitation when the two heavier polypeptides were tested in combination. By use of another L1 antiserum, all the L1 polypeptides were found to be antigenic and give immunoprecipitations. The L1 protein has a great affinity for calcium, and calcium was necessary for immunoprecipitation with the L1 subunits to occur. Autoradiographs of 2D-PAGE gels with labelled leucocytes visualized the L1 subunits in the same position as the subunits from purified, cold L1, indicating no significant alteration of the L1 protein during the purification procedure.

Blood Proteins↗