Detection of IgG-class antibodies to measles,mumps, rubella,and varicella-zoster virus using a multiplex bead immunoassay

Serologic testing for measles, mumps, rubella, and varicella (MMRV) IgG is traditionally performed by immunofluorescence assay or enzyme immunoassay (EIA). Although sensitive and specific, these methods are labor intensive, time consuming, and require separate assays for each analyte. This study evaluated the performance of the MMRV IgG AtheNA Multi-Lyte® assay using nonclinically characterized serum specimens submitted to our laboratory for routine MMRV IgG testing. Mumps (n = 492) or rubella (n = 500) IgG were initially tested by enzyme-linked fluorescent antibody (ELFA), whereas measles (n = 494) or varicella (n = 497) were analyzed by EIA. Each sample was also tested by the AtheNA Multi-Lyte assay. Discordant results were retested by the predicate method and the multiplex assay, with further discrepancies being arbitrated by a third test. Compared to EIA/ELFA for MMRV IgG, the AtheNA assay demonstrated an overall agreement of 97.4%, 98.2%, 97.6%, and 100%, respectively. Use of this multiplex assay allows for the simultaneous detection of MMRV IgG, potentially decreasing cost, sample volume requirements, aliquot errors, and hands-on testing time.     

B-1 and B-2 cell-derived immunoglobulin M antibodies are nonredundant components of the protective response to influenza virus infection

We have studied the role of secreted immunoglobulin (Ig)M in protection from infection with influenza virus and delineated the relative contributions of B-1 versus B-2 cell-derived IgM in this process. Mice deficient in secreted IgM but capable of expressing surface IgM and secreting other Ig classes show significantly reduced virus clearance and survival rates compared with wild-type controls. Irradiation chimeras in which only either B-1 or B-2 cells lack the ability to secrete IgM show mortality rates similar to those of mice in which neither B-1 nor B-2 cells secrete IgM. Dependence on both sources of IgM for survival is partially explained by findings in allotype chimeras that broadly cross-reactive B-1 cell-derived natural IgM is present before infection, whereas virus strain-specific, B-2 cell-derived IgM appears only after infection. Furthermore, lack of IgM secreted from one or both sources significantly impairs the antiviral IgG response. Reconstitution of chimeras lacking B-1 cell-derived IgM only with IgM-containing serum from noninfected mice improved both survival rates and serum levels of virus-specific IgG. Thus, virus-induced IgM must be secreted in the presence of natural IgM for efficient induction of specific IgG and for immune protection, identifying B-1 and B-2 cell-derived IgM antibodies as nonredundant components of the antiviral response.     

Secretory immunoglobulin A (sIgA) in the serum of cystic fibrosis patients

Clearly increased sIgA values were found in cystic fibrosis patients in more than 70%. The highest concentrations were seen in patients with obstructive liver disease. There were no correlations between sIgA and liver-associated enzymes. Postmortem histology and sIgA correlated well. These data suggest a pertinent role of sIgA assessment in evaluation of hepatic involvement in cystic fibrosis.     

乙型肝炎病毒感染者血清抗核抗体检测分析及临床意义

目的检测乙型肝炎病毒(HBV)感染者血清中抗核抗体(ANA)的阳性率并探讨其临床意义。方法采用间接免疫荧光法(IIF)检测120例HBV感染者、82名正常对照者的ANA。结果 120例HBV感染者中ANA阳性率为30.0%,明显高于正常对照组(4.2%);HBV感染组的ANA以低滴度(1∶100)为主,占58.3%;ANA荧光模式以颗粒型(41.7%)最为常见。结论 HBV感染可诱导以低滴度为主的ANA,其在诊断、鉴别诊断及治疗中有一定的意义,发病机制可能与自身免疫有关。     

免疫酶法检测鼻咽癌病人血清IgA/gp125抗体

建立了用表达Ｅｐｓｔｅｉｎ－Ｂａｒｒ病毒壳抗原ｇｐ１２５的重组痘苗病毒感染细胞为抗原，检测ＩｇＡ／ｇｐ１２５抗体的免疫酶法，并检测了鼻咽癌病人血清其它肿瘤病人和正常人的ＩｇＡ／ｇｐ１２５抗体，其灵敏度远远高于ＩｇＡ／ＥＡ，接近于８ｇＡ／ＭＡ和ＩｇＡ／ＶＣＡ，特异性高于ＩｇＡ／ＭＡ和ＩｇＡ／ＣＶＡ，接近于ＩｇＡ／ＥＡ。     

Innate secretory antibodies protect against natural Salmonella typhimurium infection

The production of IgA is induced in an antigen-unspecific manner by commensal flora. These secretory antibodies (SAbs) may bind multiple antigens and are thought to eliminate commensal bacteria and self-antigens to avoid systemic recognition. In this study, we addressed the role of "innate" SAbs, i.e., those that are continuously produced in normal individuals, in protection against infection of the gastrointestinal tract. We used polymeric immunoglobulin receptor (pIgR-/-) knock-out mice, which are unable to bind and actively transport dimeric IgA and pentameric IgM to the mucosae, and examined the role of innate SAbs in protection against the invasive pathogen Salmonella typhimurium. In vitro experiments suggested that innate IgA in pIgR-/- serum bound S. typhimurium in a cross-reactive manner which inhibited epithelial cell invasion. Using a "natural" infection model, we demonstrated that pIgR-/- mice are profoundly sensitive to infection with S. typhimurium via the fecal-oral route and, moreover, shed more bacteria that readily infected other animals. These results imply an important evolutionary role for innate SAbs in protecting both the individual and the herd against infections, and suggest that the major role of SAbs may be to prevent the spread of microbial pathogens throughout the population, rather than protection of local mucosal surfaces.     

Studies on a serum factor which blocks the effect of human natural thymocytotoxic antibodies

Normal human serum contains an IgM associated cytotoxic activity acting on guinea pig thymocytes. The inhibition of this cytotoxic effect by normal guinea pig serum was investigated. The blocking effect could be detected within 1 min and seemed to act by interfering with the cytotoxic factor in solution, since preincubation of human serum with autologous guinea pig serum potentiated the blocking effect, whereas no irreversible blocking effect was obtained by pre-incubation of target cells with the blocking factor. The inhibitory factor was not absorbed by incubation with thymocytes. The blocking effect was heat stabile (56 degrees C, 30 min) and detectable at both 4 degrees C and 37 degrees C. The clear effect on the cytotoxic effect of heterologous serum at 4 degrees C was in contrast to the much lower effect on the cytotoxicity of autologous serum at this temperature.     

The epidemiology and natural history of hepatitis C virus infection

Hepatitis C virus (HCV) infection is the most common chronic blood-borne infection in the United States. HCV infection is generally benign in its acute stage but tends to become chronic in more than 70% of patients, at which stage it can induce liver cirrhosis, end-stage liver disease, and hepatocellular carcinoma. Approximately 2.7 million Americans are estimated to have chronic HCV infection. Although the incidence of HCV infection is believed to be falling, the prevalence of HCV-related liver disease is rising. Better identification of risk factors for HCV transmission and improved understanding of the infection's natural history should refine measures for preventing the spread of infection and preventing complications in those infected.     

A dot-ELISA for the detection of IgG antibodies to mumps and varicella viruses

An enzyme-linked immunosorbent assay using nitrocellulose strips (dot-ELISA) for the routine laboratory detection of IgG antibodies to mumps and varicella viruses is described. The virus antigens are dotted onto nitrocellulose strips, and the dotted strips are incubated with the sera to be tested. The bound antibodies are revealed using enzyme-labeled antihuman IgG antibodies. Reliable results are obtained when the assay is carried out at 37 degrees C. The reported data indicate that the dot-ELISA can reliably be used for the detection of IgG antibodies to mumps and varicella viruses in human sera.     

The effectiveness of intravenous human immunoglobulin treatment after plasmapheresis in restoring serum immunoglobulin levels: a preliminary study.

This study was performed to examine the effects of intravenous human immunoglobulin (IVIG) on the level of serum immunoglobulin G (IgG) and its subclasses after plasmapheresis in patients with autoimmune disorders. Twenty-nine patients with predominantly rheumatoid arthritis were enrolled in this study. The plasmapheresis was performed by the use of double-filtration plasmapheresis (DFPP). Immediately after DFPP, IVIG (2.5 g, 50 ml) was intravenously administered. The treatment with IVIG had almost no effect on subjective and objective symptoms. Immediately after DFPP, the total of serum IgG was decreased by approximately 40%. After 24 h, the total of serum IgG recovered to 16% reduction in IVIG-treated patients whereas it remained at 32% reduction in nontreated patients. The beneficial effect of IVIG was significantly observed in patients who had shown 1,000-1,800 mg/dl IgG in their sera. After DFPP, IgG subclasses were decreased without change in the ratio of subclasses. Twenty percent to 30% of IgG subclasses were supplemented by the treatment with IVIG without change in the ratio of subclasses. These results suggested that the treatment with IVIG at minimal amount was safe and effective to supplement IgG for hypogammaglobulinemia after DFPP.     

小儿体外循环后血清免疫球蛋白及细胞因子的动态改变

手术创伤对机体免疫功能有影响,为了解体外循环（CPB）对小儿体液免疫功能、细胞免疫功能及补体系统的影响,本文观察了13例CPB患儿不同时间血清可溶白介素一11受体（SIL－ZR）、肿瘤坏死因子（ThF－a）、IgG、IgM、补体C3血清含量的动态变化,现报道如下。1材料及方法1．1对象13例先天性心脏病患儿,男4例、女9例,年龄2－7岁,平均41208岁。其中室间隔缺损10例、房间隔缺损2例、肺动脉瓣狭窄1例。在全麻法低温体外循环下行心内畸形矫正术,全组患儿术后均康复。于转流前、转流30’llln、松主动脉sndn、停机、停机后4h、术后第1天…     

Immunoblotting with (sub)class-specific antibodies reveals a high frequency of monoclonal gammopathies in persons thought to be immunodeficient

Immunoblotting, in combination with high-resolution electrophoresis and the use of mouse monoclonal antibodies to human (sub)class immunoglobulin (Ig) isotypes, substantially increased the sensitivity with which homogeneous Ig components (H-Ig) could be detected. Using this technique, we reinvestigated 40 selected sera, previously found to be negative for H-Ig by agar electrophoresis and immunofixation, from two groups of individuals thought to have an age-related immunodeficiency, i.e., persons older than 95 years and recipients of kidney grafts who were undergoing immunosuppressive treatment. In both groups, small single or multiple H-Ig components were found, in frequencies of 76% and 79%, respectively. For comparison, the Ig spectrum of 10 sera from patients on dialysis treatment and of 33 sera from young adult blood donors was ordinarily heterogeneous, except for one elderly patient and one blood donor with a previously unknown IgG2 deficiency. These results are complementary to the observations in some immunodeficiencies in children and indicate that the appearance of single or multiple H-Ig components in low concentration can be considered a very sensitive indicator of certain immune system disorders forming a separate category of monoclonal gammopathies.     

Unmutated immunoglobulin M can protect mice from death by influenza virus infection

To elucidate the role of class switch recombination (CSR) and somatic hypermutation (SHM) in virus infection, we have investigated the influence of the primary and secondary infections of influenza virus on mice deficient of activation-induced cytidine deaminase (AID), which is absolutely required for CSR and SHM. In the primary infection, AID deficiency caused no significant difference in mortality but did cause difference in morbidity. In the secondary infection with a lethal dose of influenza virus, both AID-/- and AID+/- mice survived completely. However, AID-/- mice could not completely block replication of the virus and their body weights decreased severely whereas AID+/- mice showed almost complete prevention from the reinfection. Depletion of CD8+ T cells by administration of an anti-CD8 monoclonal antibody caused slightly severer body weight loss but did not alter the survival rate of AID-/- mice in secondary infection. These results indicate that unmutated immunoglobulin (Ig)M alone is capable of protecting mice from death upon primary and secondary infections. Because the titers of virus-neutralizing antibodies were comparable between AID-/- and AID+/- mice at the time of the secondary infection, a defect of AID-/- mice in protection of morbidity might be due to the absence of either other Ig classes such as IgG, high affinity antibodies with SHM, or both.