Brief uncontrollable stress and psychological parameters influence human plasma concentrations of IgM and complement component C3.

Thirty-eight men participated in a study of immunological, hormonal, and psychological parameters before and after acute stress situations. A brief but acute stress was repeated daily for 4 days. This exposure caused the plasma levels of IgM and C3 to increase from Basal Day to Experimental Day 4. Significant correlations between endocrine and immunological parameters, and also between psychological measures and immunological parameters, were found. Use of psychological defense was related both to endocrine and immunological changes. The authors concluded that psychological stress may influence immunological functions both indirectly, by hormonal changes, and directly, by nervous regulation during brief but acute stress periods.

Plasma exchange in myasthenia gravis: changes in serum complement and immunoglobulins.

Serum concentrations of C4, IgG, IgA, and IgM were followed in 8 selected patients with myasthenia gravis (MG) during a 5-day course of plasma exchange (PE), using donor plasma as a replacement solution. C3 activation products (C3b, iC3b and C3c) and the terminal SC5b-9 complement complex were measured in 4 of the patients. All patients improved during the treatment, including 2 patients without detectable antibodies to AChR in serum. The main findings of the study were marked complement activation and an approximately 50% fall in the serum concentrations of IgM and C4 during PE, independent of the concentrations in the donor plasma. The concentrations of IgG and IgA did not change significantly. The fall in C4 during PE is presumably caused by C4 consumption. We postulate that the fall in IgM is an effect of a complement-induced vasodilatation and that PE-induced complement consumption may influence the effect of PE in patients with MG.

IgG Fc receptors in sera from patients with rheumatoid arthritis and systemic lupus erythematosus.

A murine monoclonal antibody to receptors for IgG (FcR) in human placenta was used in a competitive ELISA to demonstrate soluble FcR in human sera. Sera from 20 blood donors, 30 patients with systemic lupus erythematosus and 50 patients with rheumatoid arthritis were examined. Soluble FcR were demonstrated in all sera. However, significantly lower amounts of FcR were demonstrated in the patient groups as compared to blood donors. Whether this is due to increased consumption or reduced production has to be further investigated. The findings may be of significance in the pathogenesis of these diseases.

Serum concentrations of immunoglobulins and complement components in patients with recurrence after resection of gastric carcinoma.

Immunoglobulins and complement components were quantitated in sera sampled at 3-6-month intervals from 20 patients with recurrence after resection of gastric carcinoma stages I-III (pTNM). Concentrations of IgA, C3, C4, and C1-INH at clinical recurrence were increased in a significant number of patients as compared to the concentrations 3-6 months prior to recurrence. The mean concentration of C3, C4, and C1-INH were higher than prior to recurrence. At the time of recurrence, the concentrations of C3, C4, and C1-INH were higher than the corresponding postoperative concentrations among 14 patients alive and disease-free for 5 years or more. Three to six months prior to recurrence, the concentrations of C4 and C1-INH were also higher than those of the 5-year survivors. The data indicate that serial quantitation of immunoglobulins and complement components may beof value in the follow-up after resection of gastric carcinoma.

Plasma exchange in myasthenia gravis: effect on anti-AChR antibodies and other autoantibodies.

Plasma exchange (PE) was performed in 6 patients with myasthenia gravis (MG). Acetylcholine receptor (AChR) antibodies and other MG-correlated antibodies were quantified each day before, during and after PE. The antibody concentrations decreased during PE with a consisting increase between two exchanges. Repeated PE induced a transient decline in the AChR antibody concentration. The clinical improvement was maximal during the week after PE and correlated in time with increasing concentrations of AChR antibodies.

Granulocyte and lymphocyte membrane receptors in aseptic meningitis, infectious mononucleosis and other viral infections.

Granulocytes and lymphocytes from 44 patients with acute viral infections were examined for membrane receptors for sheep erythrocytes (E-R), for the Fc portion of IgG (Fc gamma-R) and for complement component C3b (C3b-R). Aseptic meningitis was associated with a decrease in Fc gamma-R and C3b-R bearing granulocytes but an increase in the proportions of lymphocytes bearing the same receptors. Patients with infectious mononucleosis (IM) had a decreased percentage of C3b-R bearing granulocytes, an increase of E-R bearing T lymphocytes and a slight decrease in the proportion of Fc gamma-R and C3b-R bearing lymphocytes. Cerebrospinal fluid from IM patients contained 92-98% T lymphocytes. The group of patients with other viral infections showed a decreased percentage of granulocytes bearing Fc gamma-R and C3b-R, and of E-R bearing lymphocytes. The decrease of Fc gamma-R and C3b-R bearing granulocytes in viral infections may be of importance in relation to the increased risk of bacterial superinfection in these patients.

Hassall's corpuscles in the thymus of fetuses, infants and children: immunological and histochemical aspects.

Hassall's corpuscles (HC) were examined for immunological and histochemical markers in cryostat sections of thymus from fetuses, infants and children. HC could not be detected before 14 weeks of gestation. Receptors for the Fc part of IgG (Fc gamma R) were demonstrated by adherence of ox erythrocytes sensitized with anti-ox IgG using a closed chamber technique. Fc gamma R were also detected by immune complexes of horseradish peroxidase (HRP) and rabbit antibodies to HRP, and with an anti-Fc gamma R serum, using indirect immunofluorescence technique and indirect immunoperoxidase technique. The staining was seen along the outer cell membranes of the HC. The Fc gamma R activity was highest in early fetal life, and decreased with increasing age. Indicator cells which detect receptors for the Fc part of IgM and for the activated third component of complement did not adhere to HC. At 14 weeks of gestation, HC showed a weak alpha-naphthyl acetate esterase (ANAE) activity, while from 16 weeks the staining intensity and pattern was unchanged. In some HC, separate cells with strong ANAE activity were seen. These cells also showed endogenous peroxidase activity, and were stained by an antibody to HLA-DR antigens. Such cells were not seen until 16 weeks of gestation. HC were stained by antibodies to IgG in fetuses older than 16 weeks, and the intensity increased gradually up to 24 weeks. Antibodies to IgM weakly stained some HC in fetuses between 16 and 36 weeks of gestation, whereas antibodies to IgA stained a minority of HC in fetuses older than 24 weeks.

The prognostic value of preoperative serum immunoglobulin and complement component concentrations in patients with gastric carcinoma.

Patients with and without recurrence of gastric carcinoma after potentially curative resection (stages I, II and III--pTNM) were studied. The preoperative serum concentrations of IgG and C1-INH were significantly different in a group of 22 patients with recurrence and a group of 33 survivors who were free from recurrence. The patients with recurrence had lower concentrations of IgG (8.3 +/- 2.6 g/l) and higher concentrations of C1-INH (0.4 +/- 0.07 g/l) than the recurrence-free survivors (10.8 +/- 3.5 and 0.35 +/- 0.08 g/l, respectively). The results indicate that preoperative quantitation of serum immunoglobulins and complement components may be helpful in predicting the prognosis in gastric carcinoma.

The prognostic value of postoperative serum immunoglobulin and complement component concentrations following gastric resection for carcinoma.

Patients clinically free from disease after potentially curative resection of gastric carcinoma, stages I, II and III (pTNM) were studied. The concentrations of immunoglobulins and complement components were quantified at 3-month intervals during the first year after surgery. The values in the individual patients showed no systematic variation with time while there was no clinical evidence of disease. The mean concentrations of C4 and C1-INH, however, were higher in 22 patients with later recurrence (0.43 +/- 0.10 and 0.43 +/- 0.07 g/l, respectively) than in 34 patients who were alive and disease-free at follow-up (0.36 +/- 0.07 and 0.36 +/- 0.04 g/l). The mean serum concentrations of IgG, IgA, IgM and C3 showed no intergroup difference. High levels of C4 and C1-INH postoperatively apparently indicate that the patient still harbours malignant disease with poor prognosis.

Localization of the binding site on IgG for solubilized placental Fc gamma receptor.

Placental Fc gamma R (FcR) inhibited the rosette formation between monocytes and rabbit IgG-sensitized erythrocytes (EA), whereas the rosette formation with granulocytes was not impaired. Staphylococcal protein A (SpA) inhibited the rosette formation with both cell types. Results obtained in absorption and agglutination experiments showed that SpA blocked the binding of FcR to IgG, and Cl did not. Furthermore, FcR did not interfere with the binding of SpA to IgG, whereas C1 affected this binding. FcR apparently bind to the C gamma 3 region. Since FcR inhibited the binding of EA to monocytes, the monocyte FcR binding site is probably also located within the C gamma 3 region.

A monoclonal antibody inhibiting human placental Fc gamma-receptor activity.

Fc gamma receptor (FcR) from human placenta was solubilized using EDTA and 2-mercaptoethanol and purified by affinity chromatography on human IgG-coated Sepharose 4B. BALB/C mice were immunized with FcR and monoclonal antibodies were obtained by growing hybridoma cells following fusion of spleen cells with P3 X 63Ag8 myeloma cells. Using an immunofluorescence technique, the IgG1 monoclonal antibody secreted by clone B1D6 stained the FcR-positive areas in sections of placental tissue. The endothelium of the foetal stem vessels stained more strongly than did the trophoblasts. The antibody also inhibited the haemadsorption to placental tissue of erythrocytes (E) sensitized with IgG antibodies (A), (EA), and inhibited the agglutination of EA by FcR. The data indicate that the monoclonal antibody reacts with the placental FcR at the binding site for IgG, or with an epitope close to the binding site. Apparently, the FcR in different anatomical areas in the placenta have a common antigenic determinant.

Stage-related correlations between immunoglobulins and complement components in preoperative sera from patients with gastric carcinoma.

Immunoglobulins A, G and M and complement components C3, C4 and C1-INH were quantitated in sera taken preoperatively from 168 patients with gastric carcinoma. The values were grouped according to stages (pTNM). The concentrations of C4 and C1-INH increased with advancing stage of disease and were above normal mean values in all stages. The concentration of IgG was below the normal mean value among all the patients and with the lowest concentration in stage III. Concentrations of IgA and C3 were above normal means but without significant relation to stages. There was a positive correlation between the concentrations of IgG and C1-INH in sera from patients with stage IV carcinoma, while the same correlation was negative in stages I-III. Although the results varied among the patients within each stage, the profiles of immunoglobulin and complement concentrations are of value in the preoperative staging of the disease.

Expression of FcIgG receptors on cultured fetal rat brain cells. Studies on normal, preneoplastic and malignant cells.

The expression of FcIgG receptor (FcR) was studied during various stages of growth and subculturing of: (1) fetal rat brain cells (FBC); (2) FBC during in vitro neoplastic transformation after a transplacental pulse of the alkylating carcinogen ethylnitrosurea in vivo, and (3) an established neoplastic brain tumor cell line. Hemadsorption of antibody-coated sheep erythrocytes was used for the detection of FcR-positive cells. Such cells were not detected in cryostat sections of fetal rat brains, but in primary cultures of FBC 1 day after the explantation. FcR-positive cells were present throughout the logarithmic-growth phase. When reaching confluency after 5-7 days in culture. FcR-positive cells could not be detected. In the secondary cultures the occurrence of FcR-positive cells showed a similar variation related to growth: The growth-related receptor was also present on cells growing into arteficial defects in confluent cultures, while the resting cells in the same cultures were FcR-negative. With further subculturing the cells became epithelioid and slowly growing without FcR. Morphologically induced differentiation of such epithelioid cells by 12-O-tetra-decanoyl phorbol-13-acetate did not change the FcR expression. We did not detect any change in the receptor expression related to the malignant transformation, and the malignant cell line was FcR-negative. Expression of FcR on FBC undergoing malignant transformation therefore seems to be mainly connected to the mode of growth (log-phase versus confluence).