Continuous intraoperative neuromonitoring (cIONM) in head and neck surgery-a review

Although the history of intraoperative neuromonitoring (IONM) dates back to the 19th century, the method did not evolve further than the mere differentiation of nerves until recently. Only the development of continuous IONM (cIONM) has allowed for non-stop analysis of excitation amplitude and latency during surgical procedures, which is nowadays integrated into the software of almost all commercially available neuromonitoring devices. The objective of cIONM is real-time monitoring of nerve status in order to recognize and prevent impending nerve injury and predict postoperative nerve function. Despite some drawbacks such as false-positive/negative alarms, technical artefacts, and rare adverse effects, cIONM remains a good instrument which is still under development. Active (acIONM) and passive (pcIONM) methods of cIONM are described in literature. The main fields of cIONM implementation are currently thyroid surgery (in which the vagal nerve is continuously stimulated) and surgery to the cerebellopontine angle (in which the facial nerve is either continuously stimulated or the discharge signal of the nerve is analyzed via pcIONM). In the latter surgery, continuous monitoring of the cochlear nerve is also established.

Clinical impact of radiographic carotid artery involvement in neck metastases from head and neck cancer

The treatment of lymph node metastases involving the carotid artery is controversial. The aim of the present study was to determine the outcomes of head and neck cancer patients with radiographic carotid artery involvement in neck metastases. A total of 27 patients with head and neck cancer and radiologically diagnosed advanced metastases involving the common carotid artery or internal carotid artery were enrolled. All patients underwent a primary or salvage neck dissection and surgical carotid peeling. The oncological outcome and survival of all patients were analyzed. Loco-regional control was observed in 13 of the 27 patients (48.1%). During follow-up, five patients (18.5%) developed second primaries and 11 (40.7%) developed distant metastases. The survival time was poor independent of regional control. The median overall survival was 1.55 years and disease-free survival was 0.71 year. Radiographic carotid artery involvement in neck metastases in head and neck cancer appears to correlate with a poor long-term prognosis, with a high rate of distant metastases despite loco-regional control.

CoOx thin film deposited by CVD as efficient water oxidation catalyst: change of oxidation state in XPS and its correlation to electrochemical activity

To reduce energy losses in water electrolysers a fundamental understanding of the water oxidation reaction steps is necessary to design efficient oxygen evolution catalysts.

Silicon based tandem cells: novel photocathodes for hydrogen production

A photovoltaic tandem cell made of amorphous silicon (a-Si) and microcrystalline silicon (μc-Si) was investigated as a photocathode for hydrogen evolution in a photoelectrochemical device. The electronic and electrochemical properties of the samples were characterized using X-ray photoemission spectroscopy (XPS) and cyclic voltammetry (CV), whereas the morphology of the surface in contact with the electrolyte was investigated by scanning electron microscopy (SEM). The electric efficiency of the tandem cell was determined to be 5.2% in a photoelectrochemical (PEC) setup in acidic solution which is only about half of the photovoltaic efficiency of the tandem cell. A significant improvement in efficiency was achieved with platinum as a catalyst which was deposited by physical vapour deposition (PVD) under ultra-high vacuum (UHV) conditions.

Thermostatted micro-reactor NMR probe head for monitoring fast reactions

A novel nuclear magnetic resonance (NMR) probe head for monitoring fast chemical reactions is described. It combines micro-reaction technology with capillary flow NMR spectroscopy. Two reactants are fed separately into the probe head where they are effectively mixed in a micro-mixer. The mixed reactants then pass through a capillary NMR flow cell that is equipped with a solenoidal radiofrequency coil where the NMR signal is acquired. The whole flow path of the reactants is thermostatted using the liquid FC-43 (perfluorotributylamine) so that exothermic and endothermic reactions can be studied under almost isothermal conditions. The set-up enables kinetic investigation of reactions with time constants of only a few seconds. Non-reactive mixing experiments carried out with the new probe head demonstrate that it facilitates the acquisition of constant highly resolved NMR signals suitable for quantification of different species in technical mixtures. Reaction kinetic measurements on a test system are presented that prove the applicability of the novel NMR probe head for monitoring fast reactions.

High-dose cyclophosphamide for severe systemic lupus erythematosus

Cytotoxic therapy is a cornerstone for patients with severe systemic lupus erythematosus (SLE). High-dose cyclophosphamide, 200 mg/kg, can induce a complete remission without the need for stem cell rescue in patients with autoimmune illnesses. Here we report on our first four patients treated for severe SLE with this treatment approach. Patients received cyclophosphamide, 200 mg/kg, divided over 4 days. Starting day 10, patients received filgrastim, 5 micrograms/kg/day, until their absolute neutrophil count (ANC) rose to 10.0 x 10(9)/l for two consecutive days. Disease activity as evaluated by scores from the Systemic Lupus Activity Measure-2, the SLE Disease Activity Index and the Responder Index for Lupus Erythematosus were completed before and after high-dose therapy. Before high-dose cyclophosphamide, SLE disease duration ranged from 8 to 21 (mean 12.5) years. Their average disease activity measured by SLAM-2 and SLEDAI was 15.5 (range 11-19) and 23.25 (range 20-26), respectively. At a median of 22 (range 12-39) months of follow-up, mean disease activity measured by SLAM-2 and SLEDAI decreased to 6.25 and 7.75, respectively. All patients experienced febrile neutropenia. No long-term morbidities or mortalities were observed. High dose cyclophosphamide is a therapy capable of decreasing disease severity in poor prognosis SLE patients. Future study is warranted for both refractory patients as well as primary therapy for patients with moderate to severe disease presentations.

Fas-mediated apoptosis eliminates B cells that acquire self-reactivity during the germinal center response to NP

C57Bl/6 mice with the lpr mutation of Fas (CD95) were tested for deviation from the genetically restricted antibody response to the hapten 4-hydroxy-3-nitrophenyl acetyl (NP). lambda1+ germinal centers (GC) with the canonical v186.2 V(H) gene element develop in lpr/lpr mice with the same time course as in wild-type (+/+) mice. In contrast to +/+ mice, however, lambda1+ GC persist in the spleens of lpr/lpr mice 25 days after immunization. Virtually all of the lambda1+ GC are reactive with NP 10 days after immunization. Sixteen days after immunization, however, many of the lambda1+ GC are not reactive with NP, and few of the lambda1+ GC are reactive with NP 25 days after immunization. The V(H) gene elements of three lambda1+NP- GC 25 days after immunization are derived by somatic mutation of v186.2, but have lost reactivity with NP. The mutated VDJs from these GC react with cells in spleen sections from +/+ and lpr/lpr mice, indicating that they represented secondary antibody responses induced by self antigens that are available as presented antigen. These data indicate that Fas-mediated apoptosis serves to eliminate a (limited) population of B cells that acquire reactivity to "self antigens" by somatic mutation of VDJs in the GC.

Circulating anticentromere CENP-A and CENP-B antibodies in patients with diffuse and limited systemic sclerosis, systemic lupus erythematosus, and rheumatoid arthritis

OBJECTIVE

To determine the disease sensitivity and specificity of testing for autoantibodies against 2 of the 3 main human centromere antigenic components, CENP-A and CENP-B (recombinant, expressed in baculovirus).

METHODS

ELISA with CENP-A and CENP-B antigens were used to test 45 sera showing a centromere pattern by immunofluorescence (IFA) and sera from 96 patients with systemic sclerosis (SSc), subdivided into diffuse (dSSc) and limited (lSSc) forms. For controls, the same tests were performed on sera from 100 patients with rheumatoid arthritis (RA), 100 with systemic lupus erythematosus (SLE), and 50 random blood donors. Sera from all the patients with SSc were also tested for the presence of anti-Scl70 antibody by ELISA (bovine antigen), and for pattern and titer by IFA (HEp-2 cells).

RESULTS

Of the 45 IFA positive sera, 93% were positive for anti-CENP-A and 91% for anti-CENP-B. There was a very good quantitative correlation between the antibody levels against these 2 centromere components (r = 0.597; p<0.001). Anti-CENP-A and B were found in 48% of patients with lSSc, and in 11% and 9%, respectively, of those with dSSc. The difference in the frequency of anti-CENP-A between the 2 patient groups was significant (chi-squared, p<0.001). Similar levels of anticentromere staining pattern by IFA were observed for these 2 groups. Anti-Scl70 was elevated in 8% of lSSc and 25% of dSSc patients; this difference was also significant (chi-squared, p = 0.02). Neither CENP-A nor CENP-B reacted with IgG from SSc patients containing anti-Scl70. The frequency of abnormal levels in patients with SLE and RA was, respectively, 11% and 3% for anti-CENP-A and 4% and 3% for anti-CENP-B. The reaction of IgG from SLE and RA patients with CENP-A was not inhibited by histone H3, i.e., it was not due to recognition of the histone-like domain in CENP-A. Thus, when 96 SSc patients were compared to 200 patients with RA and SLE, the disease specificity of anti-CENP-A and B was 93% and 96.5%, respectively.

CONCLUSION

In addition to IFA, ELISA tests for CENP-A and CENP-B yield results with similar sensitivity and specificity for the diagnosis of SSc. CENP-A and CENP-B are primarily associated with lSSc. In SSc the autoantibody response is directed simultaneously and with similar amplitude against these 2 components of the centromere structure, whereas in other autoimmune diseases the response is directed mainly against one of the 2 components.

Vascular-endothelial cadherin (CD144)- but not PECAM-1 (CD31)-based cell-to-cell contacts convey the maintenance of a quiescent endothelial monolayer

BACKGROUND

In vivo, all blood vessels are lined by a single layer of flattened noncycling endothelial cells. We tested the hypothesis that the maintenance of such a quiescent endothelial monolayer depends on homotypic contacts between not yet defined growth-inhibitory molecules located at interendothelial junctions.

METHODS

ECV304 cells, which lack endogenous vascular endothelial cadherin (VE cadherin) or CD31 expression, were transfected with cDNA encoding for the respective proteins or with the empty vector.

RESULTS

In VE cadherin transfectants, beta-catenin was targeted to junctional regions and the F-actin-based cytoskeleton formed parallel bundles reaching from one cell border to the other. In contrast, in CD31 transfectants and in empty vector cells, beta-catenin was dispersed throughout the cytoplasm, and F-actin formed short, plump and criss-cross bundles. On a two-dimensional plastic matrix, both, VE cadherin and CD31 transfectants formed clusters of polygonal cells, whereas in three-dimensional gels, only VE cadherin cells were able to form tubes. Empty vector cells grew in a fibroblast-like pattern and neither formed clusters nor tubes. Most importantly, whereas CD31 and empty vector cells grew on top of each other, formed polylayers and maintained cycling even after reaching confluence, VE cadherin cells strictly maintained a single layer of flattened cells and the numbers of cycling cells dramatically dropped after reaching a continuous monolayer.

CONCLUSION

The insertion of VE cadherin into ECV304 cells produces a cell type which mimics endothelial growth characteristics seen in vivo.

Transcription of germline VH gene elements by normal human fetal liver

Transcription of the gene elements that form the variable region of immunoglobulin heavy chains has been proposed to represent the process that controls access for the recombination enzymes in their sequential steps of catalysis. Evidence for germline transcription of VH gene elements, as part of VH to DJH recombination, has been limited to transcripts of only a few gene elements. We have examined normal fetal liver mRNA by Northern blotting and present evidence for germline transcripts from six human VH gene families. The candidate VH4 transcripts have been confirmed as germline transcripts by hybridization with 3' flanking sequences that would have been removed by recombination from mature VHDJH genes. The candidate transcripts for VH1, VH3, VH4 and VH6 have been confirmed by polymerase chain reaction amplification with primers from the 3' flanking sequences of these gene families and determination of the sequence of these products. Determination of sequence from two clones of VH1, VH3 and VH4 indicates that more than one gene from each of these families is transcribed. PCR amplification of VH4 and VH6 with primers specific for the leader sequence (exon 1) and 3' flanking sequence indicate that these transcripts are spliced, representing RNA processing. Germline transcripts from these families are also present in normal human bone marrow. These results indicate that transcriptional activation of germline VH gene elements is a general phenomenon in tissues undergoing V to DJ recombination.

VH and VL gene elements that encode human antibodies to DNA

We have determined the cDNA sequence of variable regions of heavy and light chains of three antibodies with low affinity to DNA. The variable heavy chains were found to result from utilization of VH gene elements that have been identified previously in other low-affinity anti-DNAs. These VH gene elements, VH26 and VH1.9III, are expressed in association with different D gene-encoded CDR3s than in the other antibodies. The variable light chains were found to be encoded by VL gene elements that have not previously been identified in anti-DNAs. The recurrent identification of only 10 germ line VH genes in 22 low-affinity anti-DNAs indicates that there is a high probability that all of the VH gene elements that confer reactivity with DNA have been identified. Previous studies have suggested that high-affinity antibodies to DNA result from an antigen-driven process of affinity maturation. However, only 6 of 13 high-affinity antibodies to DNA are derived from this set of low-affinity VHs, indicating that DNA is unlikely to be the driving antigen.

Flushable stent-system for internal drainage in occlusive jaundice

The effectiveness of biliary stents may be reduced as a result of obstruction by tumor material, bile salts or detritus. To circumvent this problem we developed a prosthesis system, which allows flushing and repetitive radiological control via a subcutaneous port. Prostheses were implanted in 26 patients presenting with inoperable occlusive lesions of the bile duct. Patency was regularly monitored by checking the bilirubin and alkaline phosphatase levels and using port-cholangiography. Catheter function was easily maintained in 92% of the patients and ended upon malignancy related death. In case of dysfunction, drainage could generally be restored with intensive flushing. This new flushable stent-system was easily implantable, could be exchanged without renewed percutaneous transhepatic puncture and allowed flushing, external drainage, bile probes for bacteriological examinations and follow up cholangiography via the subcutaneous placed port.

Characterization of the polymerase activity associated with cultured peripheral blood mononuclear cells from patients with Kawasaki disease

The particulate fractions of culture supernatants from peripheral blood mononuclear cells from 39 patients with Kawasaki disease (KD) were examined for the presence of particle-associated reverse transcriptase activity. The peak polymerase activity was significantly higher in cultures from KD patients compared to controls (mean = 6.4 versus 3.6 pmol of dTMP incorporated, p = 0.001). PBMC cultured between the 3rd and 9th wk after onset of fever were most likely to be associated with reverse transcriptase activity. Peak polymerase activity was positively associated with older age (r = 0.41, p = 0.01) and greater magnitude of the serum IgA response at 7-14 d after onset of fever (r = 0.45, p = 0.01) and IgM response at 6-9 wk after onset of fever (r = 0.46, p = 0.01). The appearance of enzyme activity was not associated with a decrease in viability of the cultured cells. A purified enzyme preparation showed radiolabel incorporation only with an RNA template with DNA primer. These data suggest that circulating mononuclear cells from KD patients may harbor a polymerase-associated agent and that these cells can be most readily detected in the early convalescent phase of KD from older patients who mount a marked humoral immune response.

The timing of menarche in juvenile rheumatoid arthritis

A study of the age of menarche in juvenile rheumatoid arthritis (JRA) patients was undertaken to determine what factors affect the timing of menarche. There was a significant difference between the mean age of menarche for the 68 JRA patients and 46 controls (p = 0.015). No clear etiology for this difference was elucidated. Polyarticular-onset JRA patients had the oldest age of menarche, but this finding was of marginal statistical significance (p less than 0.05,pcorr less than 0.25). The multivariate model that included onset type, steroid use, and duration of disease weakly predicted age of menarche in the JRA group. This model suggests that, exclusive of height and weight parameters, duration of disease was the most important predictor of menarche in JRA.

Identification and sequence of the VH gene elements encoding a human anti-DNA antibody

Antibodies to DNA similar to those found in patients with systemic lupus erythematosus (SLE) and autoimmune mice can be derived from the lymphocytes of normal individuals. It is not known whether these normal derived anti-DNA antibodies are made from the same VH gene elements as the anti-DNA antibodies made by SLE patients. To begin to answer this question, we examined mu chain cDNA clones from human hybrid clone C6B2 producing anti-DNA antibodies. The sequence of the 500 base pair restriction fragment containing the variable region (5' terminus) was determined and was sequenced. This antibody uses a VHII heavy chain subgroup gene, a J3 joining segment, a hitherto unknown D segment, and a previously reported leader sequence. Significant homology was found to a mouse anti-DNA antibody sequence in the use of VH subgroup in J3, and in the hypervariable regions with a shared Ser-Tyr construction in CDR1 and an identical five amino acid residue stretch in CDR2. Comparison with the limited sequence data of published SLE monoclonal anti-DNA antibodies, both human and mouse, suggests that this shared Ser-Tyr may be important in some but not all antibodies to DNA. Comparison of C6B2 antibody is made with other known antibody sequences with identification of those residues likely to be part of the antigen binding site.

Identification and sequence of the VH gene elements encoding a human anti-DNA antibody

Antibodies to DNA similar to those found in patients with systemic lupus erythematosus (SLE) and autoimmune mice can be derived from the lymphocytes of normal individuals. It is not known whether these normal derived anti-DNA antibodies are made from the same VH gene elements as the anti-DNA antibodies made by SLE patients. To begin to answer this question, we examined mu chain cDNA clones from human hybrid clone C6B2 producing anti-DNA antibodies. The sequence of the 500 base pair restriction fragment containing the variable region (5' terminus) was determined and was sequenced. This antibody uses a VHII heavy chain subgroup gene, a J3 joining segment, a hitherto unknown D segment, and a previously reported leader sequence. Significant homology was found to a mouse anti-DNA antibody sequence in the use of VH subgroup in J3, and in the hypervariable regions with a shared Ser-Tyr construction in CDR1 and an identical five amino acid residue stretch in CDR2. Comparison with the limited sequence data of published SLE monoclonal anti-DNA antibodies, both human and mouse, suggests that this shared Ser-Tyr may be important in some but not all antibodies to DNA. Comparison of C6B2 antibody is made with other known antibody sequences with identification of those residues likely to be part of the antigen binding site.

Monocyte bone degradation: in vitro analysis of monocyte activity in patients with juvenile rheumatoid arthritis

We examined the ability of the mononuclear phagocyte in vitro to degrade 45Ca-labeled bone particles to determine whether this assay allowed us to monitor disease activity in patients with juvenile rheumatoid arthritis. The monocytes from patients with juvenile rheumatoid arthritis receiving no anti-erosive therapy (n = 10) degraded significantly more bone than did cells obtained from normal controls (n = 10, P less than 0.001) or patients with juvenile rheumatoid arthritis receiving either gold thioglucose (n = 4, P less than 0.001) or D-penicillamine (n = 6, P less than 0.005). In two patients monitored for either 8 or 11 months, results of monocyte assays were found to parallel the clinical course. We conclude that in vitro monocyte bone degradation assays may provide a means of assessing joint activity in patients with juvenile rheumatoid arthritis. Further, this study and others indicate that mononuclear phagocytes are capable of causing erosive changes.

Specificity analysis of human anti-DNA antibodies

Human hybrids producing anti-DNA antibodies were generated by the fusion of pokeweed mitogen-stimulated splenic lymphocytes from a child with sickle cell anemia to GM4672. Of 19 hybrids, three (15%) produced anti-DNA antibody as detected by an enzyme linked immunosorbent assay. One subclone from each of these three hybrids was then characterized. All produced IgM antibody in large amounts ranging from 22 to 266 micrograms/ml per million cells per 24 hr. All three antibodies bound both double- and single-stranded DNA. Competitive inhibition assays revealed the greatest inhibition of DNA binding with the ribohomopolymers polyinosinic and polyguanylic acid. A complex pattern of cross-reactivity with various other polynucleotides and with some phospholipids was observed. Subtle differences were found among the three antibodies in light chain class and some of the binding specificities. By using a modified Farr assay, all three monoclonals were found to be of low to intermediate affinity. These results confirm that anti-DNA antibodies apparently equivalent to those seen in patients with SLE can be derived from "normal" nonautoimmune individuals.

Specificity analysis of human anti-DNA antibodies

Human hybrids producing anti-DNA antibodies were generated by the fusion of pokeweed mitogen-stimulated splenic lymphocytes from a child with sickle cell anemia to GM4672. Of 19 hybrids, three (15%) produced anti-DNA antibody as detected by an enzyme linked immunosorbent assay. One subclone from each of these three hybrids was then characterized. All produced IgM antibody in large amounts ranging from 22 to 266 micrograms/ml per million cells per 24 hr. All three antibodies bound both double- and single-stranded DNA. Competitive inhibition assays revealed the greatest inhibition of DNA binding with the ribohomopolymers polyinosinic and polyguanylic acid. A complex pattern of cross-reactivity with various other polynucleotides and with some phospholipids was observed. Subtle differences were found among the three antibodies in light chain class and some of the binding specificities. By using a modified Farr assay, all three monoclonals were found to be of low to intermediate affinity. These results confirm that anti-DNA antibodies apparently equivalent to those seen in patients with SLE can be derived from "normal" nonautoimmune individuals.

HLA gene frequencies in children and adults with systemic onset juvenile rheumatoid arthritis

The HLA genetic region was studied in 51 patients with systemic onset juvenile rheumatoid arthritis: 35 with childhood onset and 16 with adult onset (adult Still's disease). HLA genotypes were established by including family members, 261 of whom were also typed in the study. The most marked difference between patients and controls involved the HLA-DR4 gene, which occurred with a frequency of 0.348 in the childhood onset patients and 0.170 in the controls (chi 2 = 8.97, P = 0.0028, adjusted P = 0.017). In contrast, the adult onset patients showed a marginal increase in HLA-DR7, but were similar to controls with respect to HLA-DR4. HLA-Bw35 was increased in children with systemic onset disease, in accordance with earlier findings. The results suggest that patients with systemic onset juvenile rheumatoid arthritis have complex HLA associations which are different in childhood onset and adult onset disease.

Methylprednisolone pulse therapy for lupus nephritis: a followup study

Eight patients with acute exacerbations of lupus nephritis were treated with nine courses of alternate day intravenous methylprednisolone pulse therapy, for three doses of 30 mg/kg/day. They were followed for 24 to 68 months (mean 35.6) post pulse. Stabilization of renal function was observed. Proteinuria declined, antinuclear antibody titers fell and low serum complement levels improved. Steroids were discontinued by 24 months in four patients, and switched to alternate day therapy in the remaining five patients. No patient required the addition of cytotoxic therapy. Transient post pulse elevation of serum creatine was observed with return to pre pulse renal function by 1 month. Exacerbation of hypertension in two of the four known hypertensive patients occurred during pulse therapy; in one patient, this was associated with angina. No other untoward side effects were observed. In our experience, pulse therapy is an effective form of treatment in a subset of patients with lupus nephritis who have had recent worsening renal function. Pulse therapy may allow such patients to avoid the hazards associated with conventional long-term high dose oral corticosteroids as well as those of cytotoxic agents.

Frequency of anti-DNA antibody producing cells from normals and patients with systemic lupus erythematosus

The frequency of anti-DNA antibody producing cells from normals and patients with systemic lupus erythematosus (SLE) was determined. Peripheral blood lymphocytes (PBL) from normals and patients with SLE were cultured for 8 and 15 days with and without transformation by Epstein-Barr virus (EBV). Culture supernatants were examined for the presence of anti-DNA antibody using an enzyme-linked immunosorbent assay. We found that PBL from patients with SLE spontaneously produce anti-DNA antibodies whereas PBL from normals do not. After EBV transformation, anti-DNA antibody producing cells were detected in both cultures from patients with SLE as well as from normals. These data suggest that the high levels of anti-DNA antibody observed in patients with SLE represent activation of B cells committed to anti-DNA antibody production and that such cells are present but are not activated in normal individuals.

Complement activation by antibodies to Sm in systemic lupus erythematosus

An enzyme linked immunosorbent assay was developed to quantitate antibodies to Sm (anti-Sm) and to measure complement activation by anti-Sm in vitro. Anti-Sm in plasma of patients with systemic lupus erythematosus (SLE) were bound to purified Sm bound to polyvinyl chloride microtitre plates and assayed for bound IgG or IgM using enzyme linked anti-gamma or anti-mu. The activation of C4 by anti-Sm was measured by adding diluted normal human serum (complement) to the wells and quantitating the amount of C4 bound to the well surface using (Fab')2 goat anti-C4 followed by enzyme linked rabbit anti-goat IgG. The plasmas of 12 of 36 patients with SLE contained anti-Sm and all 12 activated complement (complement activating anti-Sm). Twenty-eight plasmas containing anti-Sm from 12 patients with SLE were studied. Ten of the 12 patients had anti-Sm of the IgG class whereas two had anti-Sm of both IgG and IgM classes. The amount of C4 activating anti-Sm correlated significantly with the in vivo activation of C4 measured by rocket immunoelectrophoresis for C4d and C4, suggesting that complement activation by anti-Sm is important in vivo.

Monocyte receptor function in patients with rheumatoid arthritis

Monocytes from patients with rheumatoid arthritis (RA), osteoarthritis (OA), and normal volunteers were studied for abnormalities of Fc and C3 receptor function. Monocytes from the majority of 22 patients with active RA showed enhanced E-rosette formation and Ea phagocytosis compared to monocytes from 20 normal volunteers and 10 OA patients, However, no significant differences in binding of EAC or uptake of iodinated aggregated gamma globulin were found among the 3 groups. Corticosteroid-treated RA patients exhibited significant depression of EA-rosette formation and phagocytosis. These results suggest that there is modulation of EA receptor function in monocytes from RA patients.