Since the early diagnosis of alpha chain disease (alphaCD)) is essential to successful treatment and to epidemiological studies, the available immunodiagnostic techniques were compared for their sensitivity, specificity and ease of performance on a panel of sixteen sera, comprising ten alphaCD sera and six control sera containing either IgA myeloma protein or high levels of polyclonal IgA. Immunoselection by immunoelectrophoresis into gel containing a specially developed anti-Fabalpha antiserum provided the most sensitive and specific detection system for alphaCD protein. The same technique using anti-light chain antiserum for immunoselection was also highly sensitive, but proved less specific, being prone to false positives with difficult IgA myeloma proteins. Somewhat less sensitive, but specific and simple to perform, was immunoelectrophoresis using an antiserum recognizing the conformational specificities of Fabalpha as well as those of the constant region of alpha chains. Immunoselection using the Ouchterlony or rocket techniques proved to be less sensitive and prone to false positives when some IgA myeloma sera were tested. (+info)
Direct method for measuring lipoprotein-X in serum.
(74/2055)
We describe a fast and easy method for routine quantitation of the abnormal lipoprotein, lipoprotein-X. The procedure is based on densitometry of precipitation areas obtained for it after serum electrophoresis in agar gel followed by precipitation with polyanions. The coefficient of variation was less than 3% in one series. Results were linearly related to concentration in the range 0.063 to 6.3 g/liter. (+info)
Conformation-specific antibodies to the alpha chain COOH terminus of hemoglobin A0.
(75/2055)
An anti-hemoglobin antiserum obtained from a sheep immunized with human carboxyhemoglobin A0 demonstrated little difference in its reactivity with deoxy- or carboxyhemoglobin A0. However, a subpopulation of this antiserum isolated by synthetic peptide affinity chromatography clearly distinguished between these two hemoglobin species. This subpopulation, designated alpha(129-141) anti-hemoglobin antibodies, represents less than 1% of the total anti-hemoglobin antibodies. They are nonprecipitating by Ouchterlony analysis, and fluorescence-quenching studies demonstrate the interaction of a single antibody binding site per hemoglobin dimer. These antibodies bind preferentially to carboxyhemoglobin with a median affinity constant of 5 X 10(8) M-1 compared to binding to deoxyhemoglobin with a binding affinity of less than 1 X 10(8) M-1. Furthermore, the presence of these antibodies in stoichiometric amounts increases the oxygen affinity of hemoglobin, and thus antibody and oxygen binding to hemoglobin can be considered as a linked function. (+info)
Lacrimal immunoglobulins and complement quantified by counter-immunoelectrophoresis.
(76/2055)
Immunoglobulin and complement concentrations of tears were measured using a sensitive electroimmunodiffusion assay. In the 13 subjects tested, the predominant immunoglobulin was secretory IgA (mean concentration 107 mug/mg protein; standard error of mean 15; n equal 17). The B1C component of complement was measurable in half of the subjects studied. The data illustrate that it is possible to quantify exactly certain humoral indices which may be important in the host defense of the eye. (+info)
A family is described in which a syndrome resembling moderately severe classic hemophilia was apparently inherited as an X chromosome-linked trait. In two affected individuals, the titer of functional antihemophilic factor varied dramatically from time to time, while the conversion of prothrombin to thrombin was impaired in no apparent relationship to AHF functional activity. A transfusion of 200 ml of fresh-frozen plasma did not correct the serum prothrombin times in either patient. In vitro, the additions of 10% of normal plasma or serum or washed plain or frozen platelets also did not normalize the serum prothrombin times. No inhibitor could be demonstrated in the blood of either patient. In one patient, RH, dissipation of infused cryoprecipitated AHF was abnormally slow, and, after an intensive course of transfusion of cryoprecipitate and whole blood, the titer of functional AHF remained at normal levels for at least 1 wk. The plasma of RH inhibited a human antibody against AHF in proportion to its titer of functional AHF (i.e., the defect was CRM-) despite the presence of relatively greater amounts of antigenic material recognized by heterologous antiserum. No qualitative abnormality of the AHF-like material in RH's plasma was identified. Inheritance of the abnormality appears superficially to be X chromosome-linked; on this assumption, three of four obligate carriers of the disorder were recognized by the presence of excess amounts of AHF-like antigens relative to AHF functional activity. This coagulation disorder has been designated Heckathorn's disease and may presage the discovery of other examples of hemophilia-related syndromes. (+info)
Demonstration by immunoelectro-osmophoresis of precipitating antibodies to a purified rubella virus antigen.
(78/2055)
The nonionic detergent Triton X-100 was used to extract antigens of rubella virus from infected tissue culture cells. Three virus-specific antigens were demonstrated by crossed immunoelectrophoresis by using a pool of human gamma globulin as antiserum. The most dominant of these antigens were purified by ion-exchange chromatography on diethylaminoethyl-cellulose. This antigen was of glucoprotein nature and had slow electrophoretic motility and low binding capacity to diethylaminoethyl-cellulose. Thus, it seems likely that the antigen is identical with the precipitating antigen of rubella virus designated b-antigen or tro-osmophoresis with precipiting antibody in sera obtained from patients recovering from acute postnatal rubella. The precipitin reaction that could be correlated to the hemaglutination-inhibition titers of the same sera appeared 12 days after onset of the disease and remained positive for several years. (+info)
Extracellular enzymes of Micropolyspora faeni found in moldy hay.
(79/2055)
Fully active enzymes with chymotrypsic activity were demonstrated in moldy hay samples where Micropolyspora faeni was found as the predominant saprophyte by using polyacrylamide gel electrophoresis. Great quantitative differences in enzymatic activity were found among moldy hay samples. (+info)
Complement breakdown products in plasma from patients with systemic lupus erythematosus and patients with membranoproliferative or other glomerulonephritis.
(80/2055)
A dynamic estimation of the involvement of the complement system in various diseases was obtained by the direct quantitation of breakdown products of C3 and of properdin factor B. The methods used were based, first on the separation of native and fragmented molecules according to their molecular size through a precipitation with polyethylene glycol and, secondly, on an immunochemical quantitation, using specific antisera for the major antigens of C3 and factor B. The sensitivity and the specificity of these methods were demonstrated by activation of complement in vitro with generation of C3 and factor B fragments. A clinical investigation was carried out in 41 patients with systemic lupus erythematosus (SLE), 31 with membranoproliferative glomerulonephritis (MPGN), 26 with other types of glomerulonephritis, and 6 with severe alcoholic cirrhosis of the liver. The following observations were made: (a) an elevated plasma level of C3d fragment of C3 was found in 68% of SLE patients, in 87% of MPGN patients, in 62% of patients with other hypocomplementemic nephritis, and in 15% of those with normocomplementemic nephritis, but in only 33% of patients with liver cirrhosis and very low levels of C3; (b) a significant difference was observed between the levels of C3 obtained with either anti-"native" C3 or anti-C3c sera for immunochemical quantitation, in patients with SLE or MPGN, indicating the presence of "altered" or fragmented C3 in plasma; (c) an elevated plasma level of Ba fragment of properdin factor B was found in 46% of SLE patients, in 67% of MPGN patients, in 50% of patients with other hypocomplementemic nephritis, and in 9% of patients with normocomplementemic nephritis, while the level of properdin factor B was only slightly decreased in these diseases; (d) in SLE and MPGN there was an inverse correlation between the levels of C3d and Ba and the level of C3 in plasma. The level of these fragments was directly correlated with the clinical manifestations of SLE; (e) some patients with a normal C3 level exhibited an elevated plasma concentration of C3 and factor B fragments, suggesting the coexistence of an increased synthesis with a hypercatabolism of complement components. Therefore, the quantitation of complement breakdown products by simple immunochemical methods provides additional information concerning the involvement of complement in disease and new features for the evaluation of the intensity of immune reactions during immune complex diseases. (+info)