Significant Increase In IgM Research Articles

Immune Response after Vaccination against Tick-Borne Encephalitis Virus (TBEV) in Horses.

(1) Background: Horses infected by a tick-borne encephalitis virus (TBEV) can develop clinically apparent infections. In humans, vaccination is the most effective preventive measure, while a vaccine is not available for horses. The objective of this study was to describe the immune response in horses after a TBEV vaccination with a human vaccine. (2) Materials and Methods: Seven healthy horses were randomised to a treatment or a control group in a stratified fashion based on TBEV-IgG concentrations on day -4. The treatment group (n = 4) was intramuscularly vaccinated using an inactivated human TBEV vaccine on days 0 and 28; the control group (n = 3) did not receive an injection. A clinical examination and blood sampling were performed on day -4, 0, 2, 4, 6, 8, 10, 14, 28, 30, 32, 34, 36, 38, 43, 56, 84, and 373. A linear mixed model analysis was used to compare IgG and IgM concentrations, neutralising antibody (nAb) titres, leucocyte count, serum amyloid A (SAA), and fibrinogen and globulin concentrations between the groups and time points. (3) Results: The clinical examination was normal in all horses at all time points. There were no significant changes in SAA, globulin, and fibrinogen concentrations and leucocyte count between the groups or time points (all p > 0.05). There was no significant increase in IgG, IgM, or nAb titres in the control group over time (all p > 0.05). In the vaccination group, there was a significant increase in IgG concentration and nAb titres after the second vaccination (p < 0.0001). There was no significant increase in IgM antibodies after the TBEV vaccination (all p > 0.05). One horse in the vaccination group had an IgM concentration above the laboratory reference on day 10. (4) Conclusions: The human TBEV vaccine did not have side effects when used in healthy horses in this study. A significant rise in TBEV-specific IgG antibodies and nAbs after the second vaccination was observed. However, IgG and nAb titres have been shown to decrease within 1 year after vaccination. The results of this study indicate that a vaccination with a human vaccine only induces a mild rise in IgM antibodies and only in previously naive horses. With no significant changes to inflammatory parameters in the vaccinated horses, it remains unclear whether vaccination with the human vaccine leads to protective immunity.

Cholera toxin and O-specific polysaccharide immune responses after oral cholera vaccination with Dukoral in different age groups of Bangladeshi participants.

Vaccination is important to prevent cholera. There are limited data comparing anti-O-specific polysaccharide (OSP) and anti-cholera toxin-specific immune responses following oral whole-cell with cholera toxin B-subunit (WC-rBS) vaccine (Dukoral, Valneva) administration in different age groups. An understanding of the differences is relevant because young children are less well protected by oral cholera vaccines than older children and adults. We compared responses in 50 adults and 49 children (ages 2 to <18) who were administered two doses of WC-rBS at a standard 14-day interval. All age groups had significant IgA and IgG plasma-blast responses to the OSP and cholera toxin B-subunit (CtxB) antigens that peaked 7 days after vaccination. However, in adults and older children (ages 5 to <18), antibody responses directed at the OSP antigen were largely IgA and IgG, with a minimal IgM response, while younger children (ages 2 to <5) mounted significant increases in IgM with minimal increases in IgA and IgG antibody responses 30 days after vaccination. In adults, anti-OSP and CtxB memory B-cell responses were detected after completion of the vaccination series, while children only mounted CtxB-specific IgG memory B-cell responses and no OSP-memory B-cell responses. In summary, children and adults living in a cholera endemic area mounted different responses to the WC-rBS vaccine, which may be a result of more prior exposure to Vibrio cholerae in older participants. The absence of class-switched antibody responses and memory B-cell responses to OSP may explain why protection wanes more rapidly after vaccination in young children compared to older vaccinees.IMPORTANCEVaccination is an important strategy to prevent cholera. Though immune responses targeting the OSP of V. cholerae are believed to mediate protection against cholera, there are limited data on anti-OSP responses after vaccination in different age groups, which is important as young children are not well protected by current oral cholera vaccines. In this study, we found that adults mounted memory B-cell responses to OSP, which were not seen in children. Adults and older children mounted class-switched (IgG and IgA) serum antibody responses to OSP, which were not seen in young children who had only IgM responses to OSP. The lack of class-switched antibody responses and memory B-cell responses to OSP in younger participants may be due to lack of prior exposure to V. cholerae and could explain why protection wanes more rapidly after vaccination in young children.

Clinico-Epidemiological Laboratory Findings of COVID- 19 Positive Patients in a Hospital in Saudi Arabia.

Understanding COVID-19's onset and clinical effects requires knowing host immune responses. To investigate the presence of IgM, IgG, and cytokine levels (IL-2 and IL-6) in individuals with COVID-19 who have had their diagnosis confirmed by PCR. This cross-sectional research included 70 adult ICU patients from King Abdullah Hospital in Bisha, Saudi Arabia. Subjects gave two blood samples. After hospital release, only 21 patients provided the second sample. Each patient provided a sample upon admission. Quantitative ELISAs evaluated IL-2, IL-6, and SARS-CoV-2-specific IgM and IgG antibodies. All patients were critically ill and unvaccinated against COVID-19. 46 (65.7%) of the patients were male, and their age range was 33-98 years (with a mean age of 66.5); 24.3%) were 51-61 years old. IgG was positive in all patients, although IgM predominated in 57/70 (81.4%) (6-1200 IU/mL). Total data analysis yielded these results. IL-6 was calculated at 10-1900 ng/mL, whereas IL-2 was 4-280. Discharged hospital patients had a statistically significant increase in IgM and IgG (P = 0.01, 0.004) but a statistically insignificant decline in IL-6 and IL-2 (P = 0.761, 0.071). Low IgM levels increased hospital stays. The study found lengthier hospital stays with higher IgG levels. The identification of IgM and IgG antibodies, greater IL-6 levels, and lower IL-2 levels can help diagnose and monitor COVID-19 infection.

Variation of COVID-19 Specific Immunoglobulin's and Some Inflammatory Factors in COVID-19 Patients in the Sabratha Isolation Center, Western Libya

Background: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic causing significant mortality and morbidity and implementation of strict isolation measures. Serological testing can diagnose illness by detecting antibodies (IgM and IgG). Testing antibodies against SARS-CoV-2 is rapid and sensitive for the auxiliary diagnosis of COVID-19. The serum levels of CRP, D-dimers, and ferritin, which may be used in risk stratification to predict severe and fatal COVID-19 in hospitalized patients. Objectives The present study aimed to investigate the variations in COVID-19 Specific Immunoglobulin's and Some Inflammatory factors in COVID-19 Patients in Sabratha isolation center, Western Libya. Subjects and Methods: Sixty Confirmed COVID-19 patients hospitalized in the Isolation Centre located in Sabratha city, Libya from the 2nd October 2020 to the 2nd June 2021, were enrolled in this prospective study. Covid-19 patients were defined as positive cases after the detection of SARS-CoV-2 RNA in oro-nasopharyngeal swab samples. Data collected included demographic, clinical, and biological factors. Also, 30 healthy individuals without any chronic disease or respiratory symptoms were recruited for the control group. Blood samples were collected by vein puncture 5 ml of venous blood was withdrawn from each participant in the study by using disposable syringes under the aseptic technique; they were then transferred to a sterile tube for estimating biochemical parameters. Biochemical parameters were determined using automated COBAS E411 and INTEGRA 400 machines in the Sabratha Isolation Centre laboratory. The statistical significance of differences between groups was evaluated with the Kruskal-Wallis H test. Results: The results showed that patients with COVID-19 had a significant (P&lt;0.0001) increase in IgM levels at 0 day, 14 days, and 21 days, respectively compared with the healthy individuals. Also, IgG levels were showed a gradual significantly (P&lt;0.0001) increase during COVID-19 Virus Infection among COVID-19 patients at 0 day, 14 days, and 21 days compared with the controls. In addition, coronavirus infection caused a significant (P&lt;0.0001) increase in D-dimer, CRP, and Ferritin levels compared with the healthy control individuals. Conclusion: It can be concluded that coronavirus infection caused a significant increase in IgM, IgG, D-dimer, CRP, and Ferritin levels at different periods compared to the controls. Further studies are needed to confirm these results. COVID-19 Specific Immunoglobulin's and Some Inflammatory factors in COVID-19 Patients These changes in IgM, IgG, D-dimer, CRP, and Ferritin levels during COVID-19 Virus Infection among COVID-19 patients may help the clinicians to better understand the COVID-19 and provide more clinical treatment options.

Controlled human infection with Neisseria lactamica induces B-cell responses that are cross-reactive with Neisseria meningitidis

Abstract Neisseria lactamica (Nlac) is a commensal of the human oropharynx. Colonisation with Nlac significantly reduces colonisation by N. meningitidis (Nmen). We hypothesised that cross-reactive adaptive cellular immune responses were responsible for this effect. 31 volunteers were inoculated intra-nasally with 105 colony-forming units of Nlac or vehicle control. Nlac/Nmen colonisation status was assessed at baseline and 7-, 14- and 28-days post-inoculation. Nlac/Nmen-specific plasma cells (PCs)/memory B-cells were quantified in PBMCs at all time points using ELISpot assays. Amongst Nlac-colonised volunteers (n=17), Nlac-specific PC frequencies/2×105 PBMCs increased significantly. Median baseline vs. post-colonisation peak Nlac-specific PC frequencies were 0 (range 0–0.5) vs. 2 (0–31) for IgM, 0 (0–1) vs. 5 (0–20.5) for IgA, and 0 (0–1) vs. 3 (0–27) for IgG (all p&amp;lt;0.0001). Nlac-specific IgG memory B-cell frequencies also increased significantly from baseline to day 28 (0.000% vs. 0.04%, p&amp;lt;0.0001). Interestingly, there was also a significant increase in IgM, IgA and IgG Nmen-specific PCs amongst Nlac-colonised volunteers. Median baseline vs. post-colonisation peak Nmen-specific PC frequencies were 0 (0–0) vs. 0 (0–30) for IgM, 0 (0–1) vs. 0.5 (0–8.5) for IgA, and 0 (0–0.5) vs. 0.5 (0–10) for IgG (all p≤0.01). There was no induction of Nlac-specific PCs/memory B-cells in the control group (n=10). These data suggest that the previously observed protective effect of Nlac on Nmen colonisation may have an immunological basis. We plan to assess the frequency/effector phenotype of Nlac-specific CD4+ memory T-cells following Nlac colonisation and hypothesise that cross-reactive CD4+ memory T-cells directed towards Nmen will be Th17.

The Effect of Used Immunostimulating Drugs with FMD Vaccine on Immunoglobulins in Sheep

In this study, the effect of used immunostimulating drugs with FMD vaccine on immunoglobulins was aimed to investigate in sheep. For this purpose 40 healthy sheep were divided into 4 groups. Blood and serum samples were taken from all animals from 0 days before the study. Blood samples were measured immediately, and IgA, IgG, IgM, IgE and Zn values from biochemical parameters were stored for measurement. Group I was applied only FMD vaccine, group II Levamisole with the FMD vaccine, group III Zinc with FMD vaccine and the last group IV AD3E was applied with FMD vaccine. After 21 days, blood and serum samples from all groups were taken again and hematologic and IgA, IgG, IgM, IgE and Zn values were compared according to the values of day 0. No statistical difference was found between the groups except for PLT in hematological parameters (p&amp;gt; 0, 05) when compared to pre-vaccination and post-vaccination. In groups II and III there was a significant increase in PLT levels. Biochemical analysis showed IgA, IgG, IgM and IgE levels to be higher in IgG (p &amp;lt;0, 05) and IgE (p &amp;lt;0,001) in groups II and III when levels compared to before vaccination. There were statistically significant increases in IgM (p &amp;lt;0.05) in group IV.

Cystatin from Filarial Parasites Suppress the Clinical Symptoms and Pathology of Experimentally Induced Colitis in Mice by Inducing T-Regulatory Cells, B1-Cells, and Alternatively Activated Macrophages.

Potential alternative therapeutic strategies for immune-mediated disorders are being increasingly recognized and are studied extensively. We previously reported the therapeutic potential of Brugia malayi derived recombinant cystatin (rBmaCys) in attenuating clinical symptoms of experimental colitis. The aim of this study was to elucidate the mechanisms involved in the rBmaCys-induced suppression of inflammation in the colon. Our results show that, the frequency of CD4+CD25+FoxP3+ regulatory T-cells was elevated in the colon and mesenteric lymph nodes. Similarly, the peritoneal macrophages recovered from the rBmaCys-treated colitis mice were alternatively activated and displayed reduced expression of TNF-α and IL-6. Another finding was significant increases in IgM+B1a-cells in the peritoneal cavity of mice following rBmaCys-treatment. These findings suggested that the regulatory cell network promoted by the rBmaCys in the colon and associated lymphoid tissues is important for its anti-inflammatory activity in the dextran sulfate sodium (DSS)-induced colitis mice.

Toxic effects of chronic exposure to dyes among workers of synthetic textile industries

Background: textile industry is one of the major industries in Egypt. However, the working environment is associated with potential health hazards. Aim of the work: to study the toxic effects of different types of dyes among workers in textile industries and its effect on their respiratory, renal, and immunological systems. Subjects and methods: this study was conducted on 50 male workers exposed to textile dyeing of different ages, selected from all textile plants with dyeing industry at Borg Al-Arab City compared with 50 males, who were not exposed to textile dye as a control group. Results: both groups were comparable as patient age, while smoking was significantly increased in exposed group (38.0% vs 14.0%). Reported symptoms such as itching, abdominal pain, etc. and respiratory symptoms were significantly increased in exposed group. There was significant increase of AST, ALT, total bilirubin and alkaline phosphatase, urea and serum creatinine in study when compared to control group. Furthermore, there was statistically significant decrease of respiratory function percentage of predicted in study group, and there was statistically significant increase of serum lead concentration in study when compared to the control group (17.18±2.35 vs 6.74±2.29 respectively). In addition, there was significant increase of IgM and IgG in study group. Conclusion: workers in textile industry were significantly exposed to health hazards especially on respiratory system. However, multi-organ affection is the role with increased oxidative stress.

TLR and CLR agonists induce anti-tumor B cell responses against peritoneal carcinomatosis

Abstract Peritoneal carcinomatosis is a condition where primary tumors metastasize into the peritoneal cavity and induce malignant ascites. The median survival of patients is poor, averaging about twenty weeks post diagnosis. Due to the high mortality rate associated with this disease and the lack of curative treatments available, it is imperative that more effective treatments be developed for peritoneal carcinomatosis. The immune system plays an important role in tumor elimination, and one strategy currently being explored to treat malignancies involves leukocyte activation through pattern recognition receptors (PRRs), including Toll-Like Receptors (TLRs) and C-type Lectin Receptors (CLRs). Our data shows that mice treated with a TLR and CLR agonist are afforded significant protection when challenged with an aggressive ascites-forming mammary tumor cell line (TA3-Ha). However, when mice lack B cells, the protection is lost. Administration of the combined treatment results in a significant increase in proliferating, antibody-producing B cells within the visceral adipose tissue (VAT). Consistent with this, the treatment induces a significant increase in IgM and complement (C′) bound to tumor cells, both of which were determined to be critical players in the anti-tumor effects. In summary, our data demonstrates pathogen associated molecular patterns can induce rapid natural IgM production that elicits anti-tumor protection via C′ activation.

Comparison between the effects of aerobic and resistive training on immunoglobulins in obese women

Obesity has adverse consequences on the immune system, causing immunosuppression, and thus increasing the incidence of infections and certain types of cancer in obese individuals. The aim of this study was to compare changes in selected immune system responses after moderate aerobic and resistive training in obese women. In total, 40 obese women (age: 35–45 years) were selected and divided into two equal groups: the aerobic training group (A), in which women received moderate-intensity aerobic training; and the resistive training group (B), in which women received moderate-intensity resistive training. Blood sampling was carried out for immunoglobulin (Ig) M and IgG in the pretest and after the 12th week of training. There was a significant increase in IgM and IgG in response to aerobic training, whereas no significant changes occurred in the resistive training group. There were significant differences in IgM and IgG between the two groups after training in favor of the aerobic training group (A). Regular moderate aerobic training seems to improve immunity compared with resisted training in obese women.

Epidermal response of rainbow trout to Ichthyobodo necator: immunohistochemical and gene expression studies indicate a Th1‐/Th2‐like switch

Infections with the parasitic flagellate Ichthyobodo necator (Henneguy, 1883) cause severe skin and gill disease in rainbow trout Oncorhynchus mykiss (Walbaum, 1792) juveniles. The epidermal disturbances including hyperplasia and mucous cell exhaustion caused by parasitization are known, but no details on specific cellular and humoral reactions have been presented. By applying gene expression methods and immunohistochemical techniques, further details of immune processes in the affected skin can be presented. A population of I.necator was established in the laboratory and used to induce an experimental infection of juvenile rainbow trout. The course of infection was followed by sampling for parasite enumeration, immunohistochemistry (IHC) and quantitative PCR (qPCR) on days 0, 5, 9 and 14 post-infection. IHC showed a significant increase in the occurrence of IgM-positive cells in the skin of the infected fish, whereas IgT-positive cells were eliminated and the number of CD8-positive cells declined. qPCR studies supported the IHC findings showing a significant increase in IgM and a decrease in the CD8 gene expression. In addition, genes encoding innate immune genes such as lysozyme, SAA and cathelicidin 2 were up-regulated. Expression of cytokines (IL-1β, IL-4/13A, IL-6, IL-8, IL-10), the cell marker CD4 and the transcription factor GATA3 showed a significant increase after infection. Cytokine profiling including up-regulation of IL-4/13A and IL-10 genes and transcription factor GATA3 connected to the proliferation of IgM producing lymphocytes suggests a partial shift towards a Th2 response associated with the I.necator infection.

Evaluation of automated assays for immunoglobulin G, M, and A measurements in dog and cat serum

Measurements of immunoglobulins (Igs) in companion animals can be useful to detect deficiencies of the humoral immune system, that can be associated with opportunistic or chronic infections, or other immune-mediated disorders including B-cell neoplasms. The purpose of this study was to evaluate commercially available automated immunoturbidimetric assays designed for human IgG, M, and A measurements in canine and feline serum using species-specific calibrators. Canine and feline serum samples with different IgG, M, and A concentrations were used for the analytical validation of the assays. Intra- and inter-assay precision, linearity under dilution, spiking recovery, and limit of detection were determined. In addition, effects of lipemia, hemolysis, and bilirubinemia were evaluated. Finally, Ig concentrations were determined in small groups of diseased dogs and cats, and compared with healthy groups. Spiking recovery and linearity under dilution tests showed that the assays measured Igs in canine and feline serum samples precisely and accurately. Intra- and inter-assay imprecisions were lower than 15% in all cases. Significantly higher IgG, IgM, and IgA levels were observed in dogs with leishmaniasis, while dogs with pyometra showed a statistically significant increase in IgM and IgA concentrations in comparison with healthy dogs. Significantly higher IgG and IgM levels were observed in FIV-infected cats compared with healthy ones. The automated human Ig assays showed adequate precision and accuracy with serum samples from dogs and cats. Also, they were able to discriminate different concentrations of Igs in healthy and diseased animals.

Blimp1 Is a Tumor Suppressor Gene in Diffuse Large B Cell Lymphoma.

Abstract 446The PRDM1/ BLIMP1 gene encodes a zinc finger transcriptional repressor that is expressed in a subset of germinal center (GC) B cells and in all plasma cells, and is required for terminal B cell differentiation. The BLIMP1 locus is biallelically inactivated by structural alterations in approximately one third of activated B cell-like diffuse large B cell lymphoma (ABC-DLBCL) (Pasqualucci et al, J Exp Med 2006). Moreover, the expression of the Blimp1 protein is absent in up to 80% of ABC-DLBCL due to alternative genetic and epigenetic mechanisms. These findings suggest that BLIMP1 may function as a tumor suppressor gene whose loss may contribute to the pathogenesis of this lymphoma type by blocking terminal B cell differentiation. To investigate the role of BLIMP1 inactivation in lymphomagenesis in vivo, we tested whether conditional deletion of the Blimp1 gene in mouse B cells can promote the growth of lymphomas recapitulating the features of ABC-DLBCL. Toward this end, a mouse model carrying a loxP-flanked exon 5 of the Blimp1 gene that can be deleted by Cre-mediated recombination (Ohinata et al, Nature 2005) was crossed with a CD19-Cre deletor strain, expressing the Cre recombinase in all B cells. The resulting mice were monitored for tumor development and survival. Consistent with previous observations in a similar model (Shapiro-Shelef et al, Immunity 2003), Blimp1 conditional knockout (Blimp1CD19KO) mice showed a severe impairment in the generation of CD138+ plasma cells and had decreased serum immunoglobulin levels of all isotypes, together with a two-fold increase in the number of PNAhiCD95+ GC B cells. Over time, significantly reduced survival was observed in the Blimp1CD19KO cohort, with only 27% of the animals being alive at 15 months of age (LogRank p value<0.0001). Macroscopic and flow cytometric analysis of the lymphoid compartments revealed the presence of splenomegaly in 32/38 (84%) Blimp1CD19KO, as compared to 1/25 (4%) age-matched wildtype (WT) littermates, and a significant increase in IgM+IgD-CD21+CD23lo splenic B cells, indicative of marginal zone B cell expansion. In addition, 79% (n=30/38) of Blimp1CD19KO mice showed markedly hyperplastic bronchus-associated lymphoid tissue (BALT). Notably, between 10 and 16 months of age 34% (13/38) of these animals developed clonal lymphoproliferative disorders with a mature B cell phenotype (B220+Pax5+) and histologic features of DLBCL (n=6) or less aggressive lymphoid proliferations (LPD: n=6; marginal zone lymphoma: n=1), in contrast with 1/27 heterozygous and 0/25 WT animals. Sequencing analysis of the rearranged immunoglobulin variable region genes in lymphoma biopsies revealed the presence of somatic mutations in 6/8 samples investigated, demonstrating their origin from a GC-experienced B cell. Moreover, immunohistochemical staining for Bcl6 and Irf4 documented a late-GC “activated” B cell phenotype (Bcl6-Irf4+) in all tumors tested (n=4), consistent with the expansion of cells that had been committed to plasma cell differentiation. These data demonstrate that Blimp1 is a bona-fide tumor suppressor gene whose B-cell specific inactivation in vivo promotes the development of lymphomas sharing features of the human ABC-DLBCL. Disclosures:No relevant conflicts of interest to declare.

Escherichia coli shares T- and B-lymphocyte epitopes with Schistosoma mansoni

In this study, we tested the cross-reaction between crude Escherichia coli antigen (ECA) and 3 crude Schistosoma mansoni antigens. The schistosomal antigens used were cercarial antigen preparation (CAP), soluble worm antigen preparation (SWAP), and soluble egg antigen (SEA). Four groups each of 3 mice received 2 intraperotineal immunizations with the above-mentioned antigens at a two-week interval. The dose of the ECA was 20 microg/100 microl PBS/mouse and that of any of the used schistosomal antigens was 50 microg/100 microl PBS/mouse. IgM and IgG reactivities and cross-reactivities were tested in individual immunized mice sera (IMS) against the above-mentioned antigens by ELISA and Western blotting. The changes in the B, CD4+ and CD8+ -T cells' counts post immunization were recorded. Priming with ECA caused significant increases in IgM (P<0.05) against CAP and SWAP, while both priming and boosting with ECA caused a significant elevation in the IgG only against SWAP. Priming and boosting with ECA or schistosomal antigens caused significant increases in IgM against ECA. Priming with ECA or SWAP caused significant elevation in IgG against ECA. In Western blotting, ECA-IMS recognized 16, 33, 38 and 94 kDa ECA peptides that cross-reacted with CAP-IMS. ECA peptides at 30 and 38 kDa cross-reacted among ECA, SWAP and SEA-IMS. CAP peptides at 40, 71, 85 and 97 kDa cross-reacted with ECA-IMS. A 59 kDa SWAP peptide cross-reacted with ECA. SEA peptides at approximately 55, 96 and 101 kDa cross-reacted with ECA-IMS. Immunization with ECA, CAP, SWAP or SEA caused significant increases in mesentric lymph nodes (MLN)-CD4+, CD8+ -T cells and MLN-B cells. For thymocytes, CD4+ -T cells significantly increased upon immunization with ECA and SWAP while CD8+-T cells significantly increased upon immunization with SWAP. It is necessary to include E. coli antigens as controls while establishing schistosomal antigens-based diagnostic tests to ensure the specificity of the detected immune responses. Characterization of the cross-reactive ECA antigens with protective potential against S. mansoni infection remains a future research objective.

Trypanosoma cruzi: Immunoglobulin isotype profiles during the acute phase of canine experimental infection with metacyclic or blood trypomastigotes

A detailed investigation has been carried out about the serological profiles of groups of dogs experimentally infected with metacyclic (MT) or blood (BT) trypomastigotes of Berenice-78 Trypanosoma cruzi strain. Peripheral blood was collected from infected dogs and uninfected controls, weekly during 35 days following the acute phase of infection, and immunoglobulin profiles were determined by ELISA. Dogs infected with BT exhibited unaltered levels of IgG2, increases in IgM, IgE, IgA, IgG and IgG1. In contrast, dogs infected with MT presented unaltered levels of IgE and IgG1 and an increase in IgM, IgA, IgG and IgG2 levels. Compared with the MT group, animals infected with BT showed significant increases in IgM on days 7, 14 and 28, in IgA on days 7, 14 and 21, in IgE on days 7 and 14, in IgG on days 14 and 28, and in IgG1 on days 7, 14 and 21. Parasitemia levels of the infected animals were measured over the same time period. No correlations were found between the immunoglobulin profiles and the parasitemia levels. The results demonstrated that the inoculum source (BT or MT) influence the immunoglobulin isotype profile that may drive distinct outcome of acute canine Chagas disease.

Parasite Burden and CD36-Mediated Sequestration Are Determinants of Acute Lung Injury in an Experimental Malaria Model

Although acute lung injury (ALI) is a common complication of severe malaria, little is known about the underlying molecular basis of lung dysfunction. Animal models have provided powerful insights into the pathogenesis of severe malaria syndromes such as cerebral malaria (CM); however, no model of malaria-induced lung injury has been definitively established. This study used bronchoalveolar lavage (BAL), histopathology and gene expression analysis to examine the development of ALI in mice infected with Plasmodium berghei ANKA (PbA). BAL fluid of PbA-infected C57BL/6 mice revealed a significant increase in IgM and total protein prior to the development of CM, indicating disruption of the alveolar–capillary membrane barrier—the physiological hallmark of ALI. In contrast to sepsis-induced ALI, BAL fluid cell counts remained constant with no infiltration of neutrophils. Histopathology showed septal inflammation without cellular transmigration into the alveolar spaces. Microarray analysis of lung tissue from PbA-infected mice identified a significant up-regulation of expressed genes associated with the gene ontology categories of defense and immune response. Severity of malaria-induced ALI varied in a panel of inbred mouse strains, and development of ALI correlated with peripheral parasite burden but not CM susceptibility. Cd36 −/− mice, which have decreased parasite lung sequestration, were relatively protected from ALI. In summary, parasite burden and CD36-mediated sequestration in the lung are primary determinants of ALI in experimental murine malaria. Furthermore, differential susceptibility of mouse strains to malaria-induced ALI and CM suggests that distinct genetic determinants may regulate susceptibility to these two important causes of malaria-associated morbidity and mortality.

Rat-to-Elephant-to-Human Transmission of Cowpox Virus

Rat-to-Elephant-to-Human Transmission of Cowpox Virus

Perinatal immunoglobulin levels in premature and small-for-date infants

In 100 low-birth-weight newborns divided into a group of prematures with adequate birth weight and a group of antenatal hypotrophics, the immunoglobulins in cord serum and in serum at 5 days were determined. The results are expressed in International Units/ml. A significant increase of IgM as compared with cord blood after 5 days of life was found in both groups. In prenatal hypotrophics insignificantly higher levels of IgM were detected both in cord and in 5-day blood. It could be supposed that the dystrophisation of some small-for-date newborns could result from intrauterine infection.

Studies on Bovine Trypanosomiasis. Serum Immunoglobulin Levels in Zebu Cattle Exposed to Natural Infection in East Africa

Immunoglobulin levels were determined in groups of Zebu cattle from tsetse-free areas of Uganda and Nigeria and from an area of enzootic trypanosomiasis in Uganda. Cattle exposed to infection for several months showed significant increases in IgM and IgG levels. Increases of 2-9 times the pre-infection levels of IgM were detectable two weeks after cattle were introduced into the enzootic area and these changes persisted for several months. Serum IgG levels showed only a 2-fold increase during the same period. Les niveaux dTmmunoglobuline ont été déterminés parmi des groupes de bétails de Zébus vivant dans des zones dépourvues de mouches tsetse en Ouganda et au Nigéria ainsi que dans une zone d’enzootie en Ouganda. On nota une augmentation significative des niveaux d’lgM et d’lgG chez les bétails exposés à l’infection pendant plusieurs mois. Des élévations d’lgM de 2 à 9 fois supérieures à celles de l’etat pré-infectieux furent décelées deux semaines après que le bétail fut introduit dans la zone enzootique et ces modifications persistèrent pendant plusieurs mois. Les niveaux d’lgG ne firent que doubler pendant le même période. Immunoglobulinkonzentrationen wurden bestimmt im Serum von Zeburindern in Gebieten in Uganda und Nigeria, die von Infestation mit Tsetsefliegen frei sind, und in einem Gebiert in Uganda mit enzootischer Trypanosomiasis. Rinder, die einer Infektionsmöglichkeit einige Monate exponiert waren, zeigten charakterische Erhöhung der IgM- und der IgG-Konzentrationen. Zwei Wochen, nachdem die Rinder in die enzootischen Gebiete gebracht worden waren, konnte man eine zwei- bis neunmalige Erhöhung der IgM-Konzentrationen in Serum feststellen und die Veränderungen hielten mehrere Monate an. Die IgG-Konzentrationen im Serum waren in der gleichen Zeit nur aus zweifache erhöht. Se determinaron los niveles de inmunoglobulinas en grupos de ganado vacuno Zebu procedentes de áreas libres de moscas tsetse en Uganda y Nigeria y de otra área en Uganda con tripanosiomiasis enzoótica. El ganado vacuno expuesto a la infeccion durante varios meses mostró un aumento significativo en las tasas de IgM e IgG. Se determinaron aumentos de 2 a 9 veces los niveles preinfectivos de IgM dos semanas después de haber introducido el ganado en las áreas enzoóticas y dichos cambios persistieron durante varios meses. Los niveles séricos de IgG solamente mostraron aumentos de dos veces durante el mismo período.