Heterophilic antibodies in sera from individuals without loxoscelism cross-react with phospholipase D from the venom of Loxosceles and Sicarius spiders

Background Loxoscelism is a severe human envenomation caused by Loxosceles spider venom. To the best of our knowledge, no study has evaluated the presence of antibodies against Loxosceles venom in loxoscelism patients without treatment with antivenom immunotherapy. We perform a comparative analysis for the presence of antibodies capable of recognizing Loxosceles venom in a group of patients diagnosed with loxoscelism and in a group of people without loxoscelism. Methods The detection of L. laeta venom, Sicarius venom and recombinant phospholipases D from Loxosceles (PLDs) in sera from people with loxoscelism (Group 1) and from healthy people with no history of loxoscelism (Group 2) was evaluated using immuno-dot blot, indirect ELISA, and Western blot. Results We found naturally heterophilic antibodies (IgG-type) in people without contact with Loxosceles spiders or any clinical history of loxoscelism. Either serum pools or single sera from Group 1 and Group 2 analyzed by dot blot tested positive for L. laeta venom. Indirect ELISA for venom recognition showed titles of 1:320 for Group 1 sera and 1:160 for Group 2 sera. Total IgG quantification showed no difference in sera from both groups. Pooled sera and purified IgG from sera of both groups revealed venom proteins between 25 and 32 kDa and the recombinant phospholipase D isoform 1 (rLlPLD1), specifically. Moreover, heterophile antibodies cross-react with PLDs from other Loxosceles species and the venom of Sicarius spider. Conclusions People without contact with the spider venom produced heterophilic antibodies capable of generating a cross-reaction against the venom of L. laeta and Sicarius spiders. Their presence and possible interference should be considered in the development of immunoassays for Loxosceles venom detection.

Heterophile antibody positive infectious mononucleosis.

OBJECTIVE: The present study has been carried out to analyse the trend of heterophile antibody positive infectious mononucleosis cases. METHODS: A total of 1741 cases of clinically suspected infectious mononucleosis from various age groups were investigated during the period January, 1986 to December, 2000 and were analysed for infectious mononucleosis (IM) specific heterophile antibody by Paul-Bunnel-Davidsohn (PBD) test. Forty seven heterophile antibody negative samples were also tested simultaneously for the presence of the IgG antibody to viral capsid antigen (VCA) and Epstein Barr nuclear antigen (EBNA) to detect the exposure to Epstein Barr Virus (EBV) infection. RESULTS: The overall percentage of EBV specific heterophile (Paul-Bunnel) antibody positivity was found to be 11.1% (194/1741). The average Paul-Bunnel antibody positivity between 1986 to 1990 was 20.5% which declined drastically to 5.7% during 1991-2000. Males comprised of 55.2% of the serologically proven IM cases. Of the 47 heterophile antibody negative cases, 38 (80.9%) and 33 (70.2%) were found to be positive for anti-VCA IgG and anti-EBNA IgG antibodies respectively. Paul Bunnel antibody positivity was found to be higher in >14 year age group patients than those below 14 years. CONCLUSION: These findings suggest that the EBV infection still continues to be endemic in this part of the country, however, a declining trend in IM cases was observed during the last decade.

Infectious mononucleosis presenting as acute hepatitis, with marked leukocytosis and renal involvement.

We report a 45-year-old lady with infectious mononucleosis due to Epstein-Barr virus. The unusual features of this case included a negative heterophil antibody test, marked leukocytosis, renal involvement and jaundice.

Infectious mononucleosis hepatitis: report of two patients.

Icteric hepatitis and fulminant hepatic failure (FHF) are rare in infectious mononucleosis (IM). We report two patients with icteric IM hepatitis; one died after developing FHF, the other recovered uneventfully. Epstein-Barr virus infection causing hepatitis and FHF should be suspected when tests for other hepatotrophic viral infections are negative.

Reticulin antibodies: relationship with endocardium-vessel-interstitium antibodies and heterophilic antibodies

Indirect immunofluorescence was used to compare reticulin antibodies, endocardium-vessel-interstitium (EVI) antibodies and heterophilic antibodies in serum samples from patients with degenerative and inflammatory diseases, Chagas' disease, or paracoccidioidomycosis and from healthy blood donors. The antigen substrates used were rat, mouse and human liver for reticulin antibodies, mouse and human heart and skeletal muscle for EVI factor, and rat heart and rat, mouse and human kidney and stomach for heterophilic antibodies. The three antibodies produced extremely similar fluorescent patterns and were present simultaneously in a large proportion of reticulin-positive serum samples. The three antibodies were significantly absorbed by heterophilic antigens such as sheep and rat red blood cells and guinea pig kidney, by Trypanosoma cruzi (an antigen associated with EVI factor) and by Paracoccidioides brasiliensis. However, they did not react with several human tissues. These results suggest that reticulin and EVI antibodies can be considered to be heterophilic antibodies

Anticorpos reticulínicos: revisäo crítica e correlaçäo com fator EVI e anticorpos heterófilos / Reticulin antibodies: critical review and correlation with EVI factor and heterophile atibodies

Neste trabalho, os autores realizaram revisäo de literatura da freqüência, padröes de fluorescência, classificaçöes, antígenos indutores e papel patogenético dos anticorpos reticulínicos (AR), EVI e heterófilos. Os anticorpos reticulínicos e EVI säo freqüentes em doenças celíca (52) e doença de Chagas (10), respectivamente. Seus antígenos indutores e seu papel patogênico säo desconhecidos. Apresentam padröes fluorescentes muito semelhantes entre si e os padröes dos anticorpos heterófilos descritos por Hawkins e col. (18), corando o tecido conjuntivo dos órgäos. Esta revisäo tem como principal objetivo realizar análise crítica comparativa entre estes três anticorpos

Mononucleosis infecciosa / Infections mononucleosis

Mononucleosis infecciosa es un padecimiento infectocontagioso causado por un virus de la familia Herpes viridae llamado virus de Epstein Barr. Sus manifestaciones en la niñez son mínimas, pudiendo presentarse como un cuadro catarral. En el adolescente y el adulto joven sus manifestaciones clínicas son características, presentando datos de afección de tejido linfoide y del sistema reticuloendotelial. Es en este último grupo de edad donde se presentan cuadros y complicaciones graves. El diagnóstico se establece con base en los criterios de Hoagland y mediante la identificación de sus diversos antígenos, así como anticuerpos dirigido contra ellos. Se ha relacionado a la mononucleosis infecciosa con el desarrollo de tumores del tejido linfoide, así como al carcinoma rinofaríngeo. No existe, a la fecha, tratamiento especial para este padecimiento viral

Investigation on immunity induced by Schistosoma spindale against S. mekongi in experimental mice.

An investigation on immunity induced by Schistosoma spindale cercariae (cattle and swamp buffalo schistosome) against S. mekongi (human schistosome) was conducted in Swiss albino mice. The studies comprised the development patterns of homologous immunity of S. spindale and heterologous immunity induced by S. spindale against S. mekongi. The development pattern of homologous immunity was studied in mice with an immunization of 100 S. spindale cercariae. At one week intervals, between 2 to 16 weeks after immunization, they were each challenged with 500 S. spindale cercariae. Significant homologous immunity, as judged by lung recovery assay five days after challenge, occurred from week 5 to week 16 with week 8 giving the highest homologous immunity (68.1% of schistosomular reduction). Using the above information mice, with an eight-week immunization period of 100 S. spindale cercariae, were tested for resistance to heterologous S. mekongi infection. The criteria used to evaluate their immune status was schistosomular lung recovery, daily egg output, worm recovery and tissue egg count. The results showed that mice immunized with S. spindale cercariae could develop heterologous immunity against S. mekongi infection. Manifestation of immunity was demonstrated by significant reduction in mean schistosomular recovery (31.4%), in mean daily egg output per female worm (16.7%), in mean worm recovery (64.2%) and in mean egg deposition in the liver tissue and intestines per female worm (37.05%).

Mononucleose infecciosa com reaçäo de Paul-Bunnell-Davidsohn positiva / Infections mononucleosis with positive Paul-Bunnell-Davidsohn reaction

Säo analisados 102 casos de mononucleose infecciosa com reaçäo de Paul-Bunnell-Davidsohn positiva, atendidos no Serviço de Doenças Transmissíveis do Hospital do Servidor Público Estadual de Säo Paulo no período de 1973 a 1985, com o objetivo de avaliar sua distribuiçäo por grupos etários e suas características clínicas. A maioria dos casos (58,8%) ocorreu em crianças com 12 anos ou menos de idade, diferindo deste modo do que se observa em países desenvolvidos. Febre (85%), linfonodemegalia cervical (93%), hepatomegalia (92%), esplenomegalia (85%) e exsudato de amígdalas (42%) foram os achados mais freqüentes. A maioria dos pacientes apresentou mais de 5.000 linfócitos/mm3 (72%), e mais de 1.000 linfócitos atípicos/mm3 (76,8%), detectando-se transaminases séricas elevadas em 58,3% dos casos. Näo foram observadas diferenças entre o quadro clínico de crianças e adultos

Anticorpos heterófilos na rotina de imunofluorescência / Heterophile antibodies in the immunofluorescence routine

Foram pesquisados auto-anticorpos em 2.132 soros de pacientes com suspeita de doença auto-imune. Além disso, foram testados 200 soros de pessoas saudáveis, que serviram como controle. Anticorpos heterófilos foram achados em 74 soros entre pacientes e controles saudáveis, sem diferença significativa. Näo houve associaçäo com qualquer doença ou sintoma. Os autores recomendaram usar fragmentos de todos os órgäos citados como substratos, a fim de evitar resultados duvidosos

Evaluación del método de detección de anticuerpos heterófilos con eritrocitos de caballo / Evaluation of a method for the detection of heterphile antibodies with erythrocytes of horses

Se estudiaron 255 pacientes entre niños y adultos, a los cuales se les indicó la prueba de Paul y Bunnell; a éstos se les realizó además una prueba que detecta anticuerpos heterófilos utilizando hematíes de caballo formalizados. En la comparación de ambas pruebas se demostró la neta superioridad evidente en sencillez y especificidad de la utilización preferencial para el diagnóstico de la mononucleosis infecciosa

Protection against scrub typhus infection engendered by the passive transfer of immune sera.

The passive transfer of convalescent sera did not protect the majority of mice against challenge with the homologous strain and was completely ineffective against challenge with strains unrelated by fluorescent antibody techniques. When the immune sera was incubated with the rickettsia in vitro and then inoculated into the mice a dramatic increase occurred in the number of surviving mice. The importance of these data in relation to published results with other species of rickettsia is discussed.