ABSTRACT
In order to determine highly immunogenic severe acute respiratory syndrome coronavirus (SARS-CoV) epitope peptides capable of inducing long-lasting immunity, we first screened immunoglobulin-G (IgG) antibodies reactive to 197 different overlapping 15-mers from the SARS-CoV proteins in the sera of three infected patients. Forty-two peptides among them were reactive to the sera from all three patients. Consequently, we tested for the reactivity of these 42 peptides to patients' sera (n = 45) at 6-month post-infection. The significantly higher levels of IgG antibodies specific to three (S791, M207 and N161) of 42 peptides were detectable in the post-infection sera from 23 (51%), 27 (60%) and 19 (42%) of 45 patients, respectively. These three peptides, recognized by their long-lasting immunity, may provide a better understanding of the immunogenicity of SARS-CoV.
Subject(s)
Immune System/immunology , Immunity/immunology , Peptides/immunology , Severe acute respiratory syndrome-related coronavirus/immunology , Enzyme-Linked Immunosorbent Assay , Humans , Immunoglobulin G/blood , Rheology , Serum/immunologyABSTRACT
The basal and stimulated intracellular cyclic AMP (cAMP) levels of peripheral blood mononuclear cells (PBMC) of 16 control subjects and 14 patients with systemic lupus erythematosus (SLE), all fulfilling the ARA criteria, were studied. No significant difference in basal cAMP level was observed between SLE patients and controls. SLE lymphocytes (both active and inactive) elicited a diminished response to aminophylline and prostaglandin E2 (PGE2). No correlation was seen between disease activity and either baseline cAMP levels or response to these stimulators. We suggest an intrinsic (not disease activity-related) impairment of the adenylate cyclase-dependent regulatory mechanism in the PBMC of SLE patients, which may result in a defective IL-2 production and IL-2 dependent biological functions.
Subject(s)
Cyclic AMP/blood , Lupus Erythematosus, Systemic/blood , Lymphocytes/metabolism , Aminophylline/pharmacology , Dinoprostone/pharmacology , Humans , In Vitro Techniques , Interleukin-2/biosynthesis , Lymphocytes/drug effects , Lymphocytes/immunologyABSTRACT
Cathepsin D-like activity was measured in the sera of 62 patients with active systemic lupus erythematosus (SLE), 9 patients with progressive systemic sclerosis, 9 patients with chronic glomerulonephritis and 18 with glomerulonephritis with nephrosis syndrome. The in vitro and in vivo effect of corticosteroid treatment on enzyme activity was also investigated. Cathepsin D-like activity appeared measurably in the sera of all patient groups but not in controls. The highest values were found in SLE patients. The increase in serum activity correlated with renal involvement. In vivo corticosteroid treatment significantly decreased serum activity in all groups except in systemic sclerosis patients. In vitro prednisolone treatment decreased enzyme activity in a dose-dependent manner. Determination of serum cathepsin D-like activity seems to be useful in the establishment of diagnosis and prognosis of SLE. Cathepsin D may be of pathogenetic significance in autoimmune disease especially in SLE.
Subject(s)
Cathepsin D/blood , Lupus Erythematosus, Systemic/enzymology , Adrenal Cortex Hormones/pharmacology , Adrenal Cortex Hormones/therapeutic use , Cathepsin D/antagonists & inhibitors , Humans , Lupus Erythematosus, Systemic/drug therapy , PrognosisABSTRACT
Circulating immune complexes (IC) were assayed in 65 patients with systemic lupus erythematosus (SLE), 34 patients with rheumatoid arthritis (RA), 40 patients with progressive systemic sclerosis (PSS), 35 patients with chronic glomerulonephritis (GN) and 30 healthy controls. Immunoglobulin components of PEG-precipitated IC from 10 patients with SLE were also determined. Cryoglobulins isolated from 11 patients with SLE were assayed for their IC-like activity. The effect of corticosteroid treatment on IC levels were also studied in SLE patients with nephritis. IC levels significantly increased in all groups but those of SLE patients were the highest values. The SLE patients with nephritis had higher levels than those without renal involvement. IgG- d IgM- but no IgA-components were found in 100% and, 90%, respectively, of IC preparations. IC-like activity of cryoglobulins were found to correlate with disease severity and appeared to be characteristic of clinical manifestations. Corticosteroid therapy significantly decreased IC levels, however, related to the entire patient group, the mean of IC level was still higher than that of healthy controls. The degree of IC level decrease (as percentage), but not absolute values, appeared to be significant in assessing disease activity. The clinical significance of IC determination and IC activity of cryoglobulins are discussed.
