Detection Of Serum IgM Antibodies Research Articles

A Study on the Clinical Application of a Rapid Diagnostic Reagent for Measles

Measles is an acute febrile rashes and infections caused by the measles virus belonging to the paramyxovirus. Each year more than twenty million peoples are affected to measles all over the world and 242,000 patients are leading to death. Traditionally the diagnosis of measles had been based on clinical symptoms in daily clinical practice. In recent years, many clinical cases do not show typical clinical manifestations and laboratory confirmation of the disease is definitely required. Lateral flow-based immuno-chromatography reagents are widely used for rapid point-of-care testing in Japanese general clinics, because it does not require special skills and facilities. We have developed a rapid diagnostic reagent for measles that employs the lateral flow-based immuno-chromatography. The correlation of the results between obtained by the diagnostic reagent and RT-PCR assay, the diagnostic reagent and detection of serum IgM antibodies, and laboratory diagnosis and clinical findings or symptoms was investigated. The correlation of the results between obtained by the diagnostic reagent and RT-PCR was the positive results that match rate of 45.5%, 100% negative match, correlation of the diagnostic reagent and detection of serum IgM antibodies positive matches to 55.6%, 100% negative match. In what had been diagnosed with measles in clinical findings so far identified with differential diagnosis of measles cases obtained by laboratory confirmation. It was concluded that the lateral flow-based rapid diagnostic reagent for measles was useful in general clinics.

Serum IgM antibody response to the galactose-inhibitable adherence lectin of Entameoba histolytica.

An ELISA for detection of serum IgM antibodies to the galactose-inhibitable adherence lectin of Entamoeba histolytica revealed that 2.8% of uninfected controls, 0.0% of controls infected with other parasites, 13.4% of asymptomatic amebic infections, 55% of colitis patients, and 77% of amebic liver abscess patients from Cairo, Egypt and Durban, South Africa had serum anti-lectin IgM antibodies. Of acute amebic colitis patients with symptoms for less than one week, only 6% possessed serum IgG anti-lectin antibodies, yet 45% had serum IgM antibodies to the amebic lectin. This compares with 65% of sera in acute colitis patients positive for lectin antigen as determined by ELISA with anti-lectin monoclonal antibodies. In conclusion, an ELISA for serum anti-lectin IgM antibodies appears to have greater clinical utility in the setting of acute amebic colitis than an ELISA for anti-lectin IgG antibodies, but is no more sensitive than an ELISA for detection of lectin antigen in sera.

Determination of specific cytomegalovirus IgM antibodies using infected air dried cells and isolated nuclei by immunoperoxidase assay

A simple immunoperoxidase assay (IPA), adapted for detection of serum IgM antibodies to cytomegalovirus (CMV) is described. The antigen consisted of CMV infected human embryonic fibroblasts or isolated nuclei. The sera were absorbed with aggregated γ-globulins prior to testing. Rabbit anti-human IgM peroxidase conjugate was used to detect IgM bound to viral antigen. In parallel the enzyme linked immunosorbent assay (ELISA) technique was used to determine IgG and IgM antibodies to CMV, respectively. All patients with acute CMV infections who were tested had CMV-specific IgM antibodies by IPA, both whole cell and nuclei antigen. The maximal IgM titers were higherby ELISA than by IPA but in 3 of the CMV patients IgM was detected earlier by IPA (with both types of antigens) than by ELISA. In 3 of 5 transplant patients with recurrent CMV infection IgM was demonstrated by immunoperoxidase techniques, while by ELISA IgM was demonstrated in only 2 of them. No cross reactivity with other herpes viruses was observed. The described IPA is simple, rapid and has the potential for widespread use in routine laboratories.

A simple and rapid method for detection of serum IgM antibodies to the rubella virus hemagglutinin

Serum IgM antibodies directed against the rubella virus hemagglutinin can be detected without prior serum fractionation. In the first step of a newly developed method, chick erythrocytes were sensitized with a subhemagglutinating dose of rubella hemagglutinin. Next, the sensitized erythrocytes were mixed with patient serum, allowing specific antibodies to react with the fixed antigens. Finally, rabbit antibodies to human IgM were used to create bridges between IgM molecules on different blood cells. The visible result was an easily read hemagglutination with sera which contain specific rubella IgM antibodies. The procedure is very simple and rapid to perform. At least 20 sera can be examined in approximately 2 h. No sophisticated instruments are needed. We have tentatively called the new method rubella anti-IgM hemagglutination (HA). Rubella antiIgM HA was more sensitive than the standard density gradient centrifugation/hemagglutination inhibition technique, but the correlation between the methods was good. Non-specific inhibitors of hemagglutination or rheumatoid factors did not seem to interfere with the specificity of the new method, and competition for antigenic sites between antibodies from the IgG/IgA and IgM classes did not seem to represent a serious, practical problem.