Combined therapy with rituximab plus cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP) for Sjögren's syndrome-associated B-cell aggressive non-Hodgkin's lymphomas

OBJECTIVE: To determine the safety and therapeutic response of a regimen consisting of cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP) plus rituximab in patients with Sj?gren's syndrome (SS) and aggressive non-Hodgkin's lymphoma (NHL). METHODS: Four SS patients with aggressive marginal zone NHL were enrolled in this trial. All patients were classified according to the newly proposed revised European-American classification of lymphoid neoplasms. Three out of four patients also had mixed cryoglobulinaemia (MC) of type II. They were treated every 3 weeks for eight cycles of CHOP. Patients also received rituximab, at a dose of 375 mg per square metre, on day 1 of each of the eight cycles of CHOP. Four weeks after completion of the eighth course of CHOP plus rituximab and every 6 months thereafter, patients were re-evaluated for response. RESULTS: Complete remission of lymphoma was achieved in all four patients. The lymphoma patients remained in remission for a period of 23, 15, 12 and 10 months respectively, while certain signs and symptoms of MC type II (purpura, peripheral neuropathy and arthralgias) significantly improved with treatment. In addition, the titres of circulating cryoglobulins and RF decreased, while C4 levels returned to normal. CONCLUSION: CHOP plus rituximab was well tolerated and proved effective in SS patients with aggressive NHL. Our observations may warrant a larger controlled trial to assess the effectiveness of this regimen in such patients.     

Glucose-6-phosphate dehydrogenase variants: reexamination of G6PD Chicago and Cornell and a new variant (G6PD Pea Ridge) resembling G6PD Chicago

Two large and unrelated families were investigated for hereditary nonspherocytic hemolytic anemia associated with deficiency of erythrocyte glucose-6-phosphate dehydrogenase (G6PD). In both families, the kinetic and electrophoretic features of the G6PD variants resembled those of G6PD Chicago. Further investigation revealed that members of one of these families previously had been characterized as having the G6PD variants Chicago and Cornell. However, it is clear that each of these terms has been applied to the same variant in this single large kindred. In the second family, we describe a newly identified variant with unique characteristics, which we have designated G6PD Pea Ridge. G6PD Pea Ridge resembles G6PD Chicago but differs in electrophoretic mobility and in a few kinetic parameters. It exhibits an unusually high Ki for NADPH and thus appears to be insensitive to product inhibition. As other cases previously considered to be the Chicago variant become more fully characterized, this probably will be shown to be a heterogeneous group of variants.     

Non-isotopic RNase cleavage assay for mutation detection in MEFV, the gene responsible for familial Mediterranean fever, in a cohort of Greek patients

BACKGROUND: The MEFV gene is responsible for familial Mediterranean fever (FMF). Several disease associated mutations have been identified. The range of genetic variation in MEFV in Greek patients has not been determined. OBJECTIVE: To describe a method that facilitates the routine screening of the entire coding sequence of MEFV (excluding exon 1). METHODS: The non-isotopic RNase cleavage assay (NIRCA) was optimised and used as a first step screening method to screen exons 2 to 10 of MEFV. Exons 2 and 10 were analysed separately at DNA level, while exons 3 to 9 were analysed together at cDNA level. The sample group consisted of 26 FMF patients diagnosed using established clinical criteria, six asymptomatic relatives, 12 patients with atypical clinical manifestations, nine patients suffering from various inflammatory diseases, and three normal individuals. All were analysed by NIRCA for mutations in the MEFV gene and direct sequencing was applied subsequently to confirm the results. RESULTS: MEFV mutations were identified in 25 of 26 typical FMF patients and in two of 12 patients with atypical manifestations. NIRCA results were in concordance with sequencing findings in all sequences analysed, suggesting that the method is highly reliable in this disease. Sixteen alterations of MEFV were identified (eight missense mutations and eight single nucleotide polymorphisms). CONCLUSIONS: NIRCA can be used for rapid screening of the coding sequence of the MEFV gene in patients suspected of suffering from FMF.     

Enzyme immunoassays for the detection of IgG and IgM anti-dsDNA antibodies: clinical significance and specificity

A solid phase Enzyme-Linked Immunosorbent Assay (ELISA) was developed for the measurement of IgG and IgM antibodies to double-stranded DNA (anti-dsDNA). This method is sensitive, specific, relatively simple and suitable for routine use. Thus, we evaluated sera from 224 Greek patients with the following autoimmune rheumatic diseases: 54 patients with classical rheumatoid arthritis (RA), 50 patients with primary Sj?gren's syndrome (SS), 41 patients with systemic lupus erythematosus (SLE), 30 patients with scleroderma, 20 patients with idiopathic Raynaud's phenomenon (IRP) and 29 patients with juvenile rheumatoid arthritis (JRA). Sera from 119 age- and sex-matched healthy blood donors were tested as normal controls. The presence of both IgG and IgM anti-dsDNA highly correlated with SLE. However, IgM anti-dsDNA levels were significantly lower. Serum complement C3 and C4 levels correlated negatively with anti-dsDNA levels in the SLE group. Finally, in sequential sera from five SLE patients, the anti-dsDNA activity proved to be a relatively sensitive marker of SLE activity.     

Demonstration of reversible priming of human neutrophils using platelet- activating factor

Exposure of neutrophils to agents such as lipopolysaccharide, tumor necrosis factor-alpha (TNF-alpha), and the granulocyte-macrophage colony-stimulating factor causes a major upregulation of subsequent agonist-induced NADPH oxidase activation. This priming effect is a prerequisite for neutrophil-mediated tissue damage and has been widely considered to be an irreversible process. We have investigated the potential for neutrophils to recover from a priming stimulus by studying the effects of platelet-activating factor (PAF). PAF did not stimulate respiratory burst activity directly, but caused a rapid (maximal at 10 minutes) and concentration-dependent (EC50 50.2 nmol/L) increase in N-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated superoxide anion release. At time-points > 10 minutes, this priming effect spontaneously declined, with return to basal levels of fMLP- stimulated superoxide anion generation by 120 minutes. An identical priming time-course was observed with N-methyl carbamyl PAF, a nonmetabolizable analogue of PAF, indicating that the transient nature of PAF-induced priming was not secondary to PAF metabolism. Two structurally diverse PAF receptor antagonists (UK-74,505 and WEB 2086), added 10 minutes after PAF addition, increased the rate of decay of the priming effect. In contrast, TNF-alpha-induced priming, which was of a similar magnitude to that observed for PAF, was slower to evolve (maximal at 30 minutes) and remained constant for at least 120 minutes. The reversible nature of PAF-induced priming was confirmed by demonstrating that PAF-, but not TNF-alpha-, induced cell polarization (shape change) and CD11b-dependent neutrophil binding of albumin-coated latex beads was also transient, with return to basal, unstimulated levels by 120 minutes. Furthermore, cells that had spontaneously deprimed following PAF exposure retained their capacity to be fully reprimed by a subsequent addition of either PAF or TNF-alpha. These data imply that neutrophil priming is not an irreversible event: the demonstration of a cycle of complete priming, depriming, and repriming offers the potential for functional recycling of neutrophils at sites of inflammation.     

Differential expression of CD11b/CD18 (Mo1) and myeloperoxidase genes during myeloid differentiation

During the course of differentiation of early human myeloid cells toward monocytes and granulocytes, cell surface expression of the cell adhesion molecule, CD11b/CD18 (Mo1) increases dramatically and expression of myeloperoxidase (MPO), a bacteriocidal enzyme, decreases markedly. Using the inducible promyelocytic cell line HL-60 as a model, we studied the mRNA expression of these genes. Differentiation of these cells along both a monocytic and a granulocytic pathway demonstrated that the mRNA levels of the two subunits of CD11b/CD18 increased in a pattern temporally and quantitatively similar to the increase in cell surface expression of this heterodimer. In contrast, the expression of MPO mRNA decreased in a temporal and quantitative pattern similar to the known decrease in MPO protein during differentiation, suggesting that regulation of these myeloid-specific proteins may occur at the level of mRNA expression. These findings have important implications with regard to the nature of the block in differentiation in acute nonlymphocytic leukemia and the regulation of myeloid gene expression.     

The significance of HLA-DRB1 matching on clinical outcome after HLA-A, B, DR identical unrelated donor marrow transplantation

Despite matching for serologically defined HLA-A, B, DR antigens, acute graft-versus-host disease (GVHD) is a major complication contributing to increased morbidity and mortality in patients who undergo marrow transplantation from unrelated donors. The extent to which unrecognized mismatching for alleles that encode DR1-DR18 contribute to the increased risk of acute GVHD and overall survival is unknown. We analyzed 364 patients and their HLA-A, B, DR serologically matched donors to determine whether molecular typing of DRB1 alleles can allow more accurate donor/recipient matching and thereby improve clinical outcome after marrow transplantation. DRB1 alleles were typed by sequence-specific oligonucleotide probe hybridization methods. Selected alleles were confirmed by DNA sequencing. Of the 364 pairs, 305 were matched and 59 were mismatched for DRB1. The probability of moderate to severe acute GVHD was .48 for the matched and .70 for the mismatched patients. Compared with mismatched patients, the estimated relative risk (RR) of GVHD for matched patients was .58 (95% confidence interval [CI], .40 to .85). DRB1 matching decreased the risk of transplant- related mortality (RR, .66; 95% CI, .44 to .97) and was associated with decreased overall mortality (RR, .71; 95% CI, .51 to 1.0). Therefore, matching DRB1 alleles of the donor and recipient decreases the risk of acute GVHD and improves survival after unrelated marrow transplantation. These results indicate that prospective matching of patients and donors for DRB1 alleles is warranted.