Pentaglobin (immunoglobulin M-enriched immunoglobulin) as adjuvant therapy for premature and very low-birth-weight neonates with sepsis.

OBJECTIVES: The purpose of this research was to determine the effectiveness of Pentaglobin® as adjuvant therapy in the treatment of sepsis in preterm newborns. MATERIALS AND METHODS: It was a prospective, observational, randomized study for 272 premature neonates and very low birth weight (VLBW) that were diagnosed with sepsis carried at neonatal intensive care units. The patients randomized into control group who received standard sepsis antibiotic treatments, and an intervention group who received Pentaglobin® 5 ml/kg daily for 3 consecutive days as an adjunct therapy to a standard sepsis antibiotic treatment. RESULTS: Multiple organisms that isolated from culture specimens were Gram-negative bacteria, Gram-positive, and candida (56.25%, 42.28%, and 1.47%, respectively). The disease duration was distinctively longer in patients who were treated by the standard antibiotic protocol (mean ± standard deviation [SD]: 30.76 ± 3.97, odds ratio [OR]: 30.76, 95% confidence interval [CI]: 30.051, 31.473) comparing to the patients who received Pentaglobin adjuvant therapy (mean ± SD: 26.48 ± 5.55, OR: 26.48, 95% CI: 25.489, 27.477) (P < 0.000). Patients treated by standard antibiotic protocol were associated to a substantially increased risk of death (11.76%, hazard ratio 4.400, 95% CI: 1.432, 13.529, P = 0.009). CONCLUSION: Neonatal sepsis is more common in premature and VLBW newborns, and Pentaglobin® management of newborn nosocomial sepsis might be used in addition to other therapies.

Antibody-Mediated Targeting of Antigens to Intestinal Aminopeptidase N Elicits Gut IgA Responses in Pigs.

Many pathogens enter the host via the gut, causing disease in animals and humans. A robust intestinal immune response is necessary to protect the host from these gut pathogens. Despite being best suited for eliciting intestinal immunity, oral vaccination remains a challenge due to the gastrointestinal environment, a poor uptake of vaccine antigens by the intestinal epithelium and the tolerogenic environment pervading the gut. To improve uptake, efforts have focused on targeting antigens towards the gut mucosa. An interesting target is aminopeptidase N (APN), a conserved membrane protein present on small intestinal epithelial cells shown to mediate epithelial transcytosis. Here, we aimed to further optimize this oral vaccination strategy in a large animal model. Porcine APN-specific monoclonal antibodies were generated and the most promising candidate in terms of epithelial transcytosis was selected to generate antibody fusion constructs, comprising a murine IgG1 or porcine IgA backbone and a low immunogenic antigen: the F18-fimbriated E. coli tip adhesin FedF. Upon oral delivery of these recombinant antibodies in piglets, both mucosal and systemic immune responses were elicited. The presence of the FedF antigen however appeared to reduce these immune responses. Further analysis showed that F18 fimbriae were able to disrupt the antigen presenting capacity of intestinal antigen presenting cells, implying potential tolerogenic effects of FedF. Altogether, these findings show that targeted delivery of molecules to epithelial aminopeptidase N results in their transcytosis and delivery to the gut immune systems. The results provide a solid foundation for the development of oral subunit vaccines to protect against gut pathogens.

Long-Term Persistence and Relevant Therapeutic Impact of High-Titer Viral-Neutralizing Antibody in a Convalescent COVID-19 Plasma Super-Donor: A Case Report.

A convalescent, non-severe, patient with COVID-19 was enrolled as a hyper-immune plasma voluntary donor by the Immuno-Hematology and Transfusion Unit of the Regina Elena National Cancer Institute in Rome, under the TSUNAMI national study criteria. During a nearly 6-month period (May-October 2020), the patient was closely monitored and underwent four hyperimmune plasma collections. Serum SARS-CoV-2 (anti-S + anti-N) IgG and IgM, anti-S1 IgA, and neutralizing titers (NTs) were measured. Anti-SARS-CoV-2 antibody levels steadily decreased. No correlation was found between anti-S/anti-N IgG and IgM levels and viral NT, measured by either a microneutralization test or the surrogate RBD/ACE2-binding inhibition test. Conversely, NTs directly correlated with anti-S1 IgA levels. Hyperimmune donor plasma, administered to five SARS-CoV-2 patients with persistent, severe COVID-19 symptoms, induced short-term clinical and pathological improvement. Reported data suggest that high NTs can persist longer than expected, thus widening hyperimmune plasma source, availability, and potential use. In vitro RBD/ACE2-binding inhibition test is confirmed as a convenient surrogate index for neutralizing activity and patients' follow-up, suitable for clinical settings where biosafety level 3 facilities are not available. IgA levels may correlate with serum neutralizing activity and represent a further independent index for patient evaluation.

Novel oncolytic adenovirus expressing enhanced cross-hybrid IgGA Fc PD-L1 inhibitor activates multiple immune effector populations leading to enhanced tumor killing in vitro, in vivo and with patient-derived tumor organoids.

BACKGROUND: Despite the success of immune checkpoint inhibitors against PD-L1 in the clinic, only a fraction of patients benefit from such therapy. A theoretical strategy to increase efficacy would be to arm such antibodies with Fc-mediated effector mechanisms. However, these effector mechanisms are inhibited or reduced due to toxicity issues since PD-L1 is not confined to the tumor and also expressed on healthy cells. To increase efficacy while minimizing toxicity, we designed an oncolytic adenovirus that secretes a cross-hybrid Fc-fusion peptide against PD-L1 able to elicit effector mechanisms of an IgG1 and also IgA1 consequently activating neutrophils, a population neglected by IgG1, in order to combine multiple effector mechanisms. METHODS: The cross-hybrid Fc-fusion peptide comprises of an Fc with the constant domains of an IgA1 and IgG1 which is connected to a PD-1 ectodomain via a GGGS linker and was cloned into an oncolytic adenovirus. We demonstrated that the oncolytic adenovirus was able to secrete the cross-hybrid Fc-fusion peptide able to bind to PD-L1 and activate multiple immune components enhancing tumor cytotoxicity in various cancer cell lines, in vivo and ex vivo renal-cell carcinoma patient-derived organoids. RESULTS: Using various techniques to measure cytotoxicity, the cross-hybrid Fc-fusion peptide expressed by the oncolytic adenovirus was shown to activate Fc-effector mechanisms of an IgA1 (neutrophil activation) as well as of an IgG1 (natural killer and complement activation). The activation of multiple effector mechanism simultaneously led to significantly increased tumor killing compared with FDA-approved PD-L1 checkpoint inhibitor (Atezolizumab), IgG1-PDL1 and IgA-PDL1 in various in vitro cell lines, in vivo models and ex vivo renal cell carcinoma organoids. Moreover, in vivo data demonstrated that Ad-Cab did not require CD8+ T cells, unlike conventional checkpoint inhibitors, since it was able to activate other effector populations. CONCLUSION: Arming PD-L1 checkpoint inhibitors with Fc-effector mechanisms of both an IgA1 and an IgG1 can increase efficacy while maintaining safety by limiting expression to the tumor using oncolytic adenovirus. The increase in tumor killing is mostly attributed to the activation of multiple effector populations rather than activating a single effector population leading to significantly higher tumor killing.

Topical application of nebulized human IgG, IgA and IgAM in the lungs of rats and non-human primates.

BACKGROUND: Recurrent and persistent infections are known to affect airways of patients with Primary Immunodeficiency despite appropriate replacement immunoglobulin serum levels. Interestingly, patients with Chronic Obstructive Pulmonary Disease or with non-CF bronchiectasis also show similar susceptibility to such infections. This may be due to the limited availability of immunoglobulins from the systemic circulation in the conductive airways, resulting in local immunodeficiency. Topical application of nebulized plasma-derived immunoglobulins may represent a means to address this deficiency. In this study, we assessed the feasibility of nebulizing plasma-derived immunoglobulins and delivering them into the airways of rats and non-human primates. METHODS: Distinct human plasma-derived immunoglobulin isotype preparations were nebulized with an investigational eFlow® nebulizer and analyzed in vitro or deposited into animals. Biochemical and immunohistological analysis of nebulized immunoglobulins were then performed. Lastly, efficacy of topically applied human plasma-derived immunoglobulins was assessed in an acute Streptococcus pneumoniae respiratory infection in mice. RESULTS: Characteristics of the resulting aerosols were comparable between preparations, even when using solutions with elevated viscosity. Neither the structural integrity nor the biological function of nebulized immunoglobulins were compromised by the nebulization process. In animal studies, immunoglobulins levels were assessed in plasma, broncho-alveolar lavages (BAL) and on lung sections of rats and non-human primates in samples collected up to 72 h following application. Nebulized immunoglobulins were detectable over 48 h in the BAL samples and up to 72 h on lung sections. Immunoglobulins recovered from BAL fluid up to 24 h after inhalation remained structurally and functionally intact. Importantly, topical application of human plasma-derived immunoglobulin G into the airways of mice offered significant protection against acute pneumococcal pneumonia. CONCLUSION: Taken together our data demonstrate the feasibility of topically applying plasma-derived immunoglobulins into the lungs using a nebulized liquid formulation. Moreover, topically administered human plasma-derived immunoglobulins prevented acute respiratory infection.

Anti-N-methyl-d-aspartate receptor encephalitis in an older patient presenting with a rapid onset of delusions and amnesia.

We present the case of a 77-year-old patient with a rapid onset of delusions, amnesia, agitation, insomnia and no previous psychiatric history, who was diagnosed with anti-N-methyl-d-aspartate receptor encephalitis. This case report highlights the importance of including autoimmune encephalitis in the differential diagnosis of older patients presenting with rapid onset psychiatric episodes.

Personalized medicine with IgGAM compared with standard of care for treatment of peritonitis after infectious source control (the PEPPER trial): study protocol for a randomized controlled trial.

BACKGROUND: Peritonitis is responsible for thousands of deaths annually in Germany alone. Even source control (SC) and antibiotic treatment often fail to prevent severe sepsis or septic shock, and this situation has hardly improved in the past two decades. Most experimental immunomodulatory therapeutics for sepsis have been aimed at blocking or dampening a specific pro-inflammatory immunological mediator. However, the patient collective is large and heterogeneous. There are therefore grounds for investigating the possibility of developing personalized therapies by classifying patients into groups according to biomarkers. This study aims to combine an assessment of the efficacy of treatment with a preparation of human immunoglobulins G, A, and M (IgGAM) with individual status of various biomarkers (immunoglobulin level, procalcitonin, interleukin 6, antigen D-related human leucocyte antigen (HLA-DR), transcription factor NF-κB1, adrenomedullin, and pathogen spectrum). METHODS/DESIGN: A total of 200 patients with sepsis or septic shock will receive standard-of-care treatment (SoC). Of these, 133 patients (selected by 1:2 randomization) will in addition receive infusions of IgGAM for 5 days. All patients will be followed for approximately 90 days and assessed by the multiple-organ failure (MOF) score, by the EQ QLQ 5D quality-of-life scale, and by measurement of vital signs, biomarkers (as above), and survival. DISCUSSION: This study is intended to provide further information on the efficacy and safety of treatment with IgGAM and to offer the possibility of correlating these with the biomarkers to be studied. Specifically, it will test (at a descriptive level) the hypothesis that patients receiving IgGAM who have higher inflammation status (IL-6) and poorer immune status (low HLA-DR, low immunoglobulin levels) have a better outcome than patients who do not receive IgGAM. It is expected to provide information that will help to close the knowledge gap concerning the association between the effect of IgGAM and the presence of various biomarkers, thus possibly opening the way to a personalized medicine. TRIAL REGISTRATION: EudraCT, 2016-001788-34; ClinicalTrials.gov, NCT03334006 . Registered on 17 Nov 2017. Trial sponsor: RWTH Aachen University, represented by the Center for Translational & Clinical Research Aachen (contact Dr. S. Isfort).

Success of anti-CD20 monoclonal antibody treatment for severe autoimmune hemolytic anemia caused by warm-reactive immunoglobulin A, immunoglobulin G, and immunoglobulin M autoantibodies in a child: a case report.

BACKGROUND: Autoimmune hemolytic anemia is rare in children. First-line therapies for this disease consist of corticosteroids and intravenously administered immunoglobulin that are effective in most patients. However, a small proportion of cases (5 to 10%) is refractory to these therapies and may represent a medical emergency, especially when hemolysis is due to warm immunoglobulin M. Recently, reports of the use of rituximab in adult autoimmune diseases have shown promising results. In children, there are few studies on the use of rituximab in the treatment for autoimmune hemolytic anemia, especially on its long-term efficacy and adverse effects. CASE PRESENTATION: Here, we report the case of a 10-year-old Tunisian girl with refractory acute autoimmune hemolytic anemia caused by warm-reactive immunoglobulin A, immunoglobulin G, immunoglobulin M, and C3d autoantibodies. First-line treatments using corticosteroids and intravenously administered immunoglobulin were ineffective in controlling her severe disease. On the other hand, she was successfully treated with rituximab. In fact, her hemolytic anemia improved rapidly and no adverse effects were observed. CONCLUSIONS: The case that we report in this paper shows that rituximab could be an alternative therapeutic option in severe acute autoimmune hemolytic anemia with profound hemolysis refractory to conventional treatment. Moreover, it may preclude the use of plasmapheresis in such an urgent situation with a sustained remission.

Intestinal IgA as a modulator of the gut microbiota.

Accumulating evidence suggests that dysbiosis plays a role in the pathogenesis of intestinal diseases including inflammatory bowel disease (IBD) as well as extra-intestinal disorders. As a modulator of the intestinal microbiota, we isolated a mouse monoclonal IgA antibody (clone W27) with high affinities for multiple commensal bacteria, but not for beneficial bacteria such as Lactobacillus casei (L. casei). Via specific recognition of an epitope in serine hydroxymethyltransferase (SHMT), a bacterial metabolic enzyme, W27 IgA selectively inhibited the in vitro growth of bound bacteria, including Escherichia coli (E. coli), while having no effect on unbound beneficial bacteria such as L. casei. By modulating the gut microbiota in vivo, oral administration of W27 IgA effectively prevented development of colitis in several mouse models. Here we discuss how intestinal IgA modulates the gut microbiota through recognition of SHMT.

Oral immunoglobulin for preventing necrotizing enterocolitis in preterm and low birth weight neonates.

BACKGROUND: Necrotizing enterocolitis (NEC) is the most common emergency involving the gastrointestinal tract occurring in the neonatal period. There have been published reports that suggest that oral immunoglobulins (Ig)A and IgG produce an immunoprotective effect in the gastrointestinal mucosa. OBJECTIVES: To determine the effect of oral immunoglobulin on the incidence of necrotizing enterocolitis and other complications in preterm or low birth weight (or both) neonates. SEARCH METHODS: We used the standard search strategy of the Cochrane Neonatal Group. We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2016, Issue 1), PubMed (1966 to January 2016), CINAHL (1982 to January 2016) and EMBASE (1980 to January 2016) and conference proceedings. SELECTION CRITERIA: All randomized or quasi-randomised controlled trials where oral immunoglobulins were used as prophylaxis against NEC in preterm (less than 37 weeks' gestation) or low birth weight (less than 2500 gram), or both, neonates. DATA COLLECTION AND ANALYSIS: We performed data collection and analysis in accordance with the standard methods of the Cochrane Neonatal Review Group. MAIN RESULTS: The search identified five studies on oral immunoglobulin for the prevention of NEC of which three met the inclusion criteria. In this review of the three eligible trials (including 2095 neonates), the oral administration of IgG or an IgG/IgA combination did not result in a significant reduction in the incidence of definite NEC (typical risk ratio (RR) 0.84, 95% confidence interval (CI) 0.57 to 1.25; typical risk difference (RD) -0.01, 95% CI -0.03 to 0.01; 3 studies, 1840 infants), suspected NEC (RR 0.84, 95% CI 0.49 to 1.46; RD -0.01, 95% CI -0.02 to 0.01; 1 study, 1529 infants), need for surgery (typical RR 0.21, 95% CI 0.02 to 1.75; typical RD -0.03, 95% CI -0.06 to 0.00; 2 studies, 311 infants) or death from NEC (typical RR 1.10, 95% CI 0.47 to 2.59; typical RD 0.00, 95% CI -0.01 to 0.01; 3 studies, 1840 infants). AUTHORS' CONCLUSIONS: Based on the available trials, the evidence does not support the administration of oral immunoglobulin for the prevention of NEC. There are no randomized controlled trials of oral IgA alone for the prevention of NEC.

Comparison of prophylactic use of intravenous immunoglobulin versus Pentaglobin® in pediatric patients after hematopoietic stem cell transplantation.

There are few studies evaluating the use of IgM-enriched IVIG (Pentaglobin(®) ) in HSCT recipients. This study aimed to compare the efficacy of prophylactic use of IVIG versus prophylactic use of Pentaglobin(®) within the first 100 days after allogeneic HSCT. We performed a prospective, randomized study of the use of prophylactic IVIG versus prophylactic use of Pentaglobin(®) in patients after allogeneic HSCT. The first dose of IVIG or Pentaglobin(®) was given before conditioning regimen and after transplant was given on day +1, +8, +15, and +22. And then, it was given if IgG level was below 400 mg/dL. Twenty-seven patients in IVIG group and 32 patients in Pentaglobin(®) group were included in the study. There were no significant differences in the duration of neutropenia, hospitalization, fever, and in the number of pyrexial episode, septicemia, bacteremia, local infection, CMV infection, acute GVHD, VOD, and adverse events between the IVIG group and Pentaglobin(®) group. Randomized placebo-controlled trials are needed to conclude that utilization of IVIG or Pentaglobin(®) has no beneficial effect in HSCT.

Streptococcus pneumoniae antibody titres in patients with primary antibody deficiency receiving intravenous immunoglobulin (IVIG) compared to subcutaneous immunoglobulin (SCIG).

Intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin (SCIG) are effective in the treatment of patients with primary antibody deficiency disorders (PAD). The purpose of this study was to evaluate Streptococcus pneumoniae (Spn) antibody titres to 14 serotypes in patients receiving IVIG compared to SCIG and to correlate Spn antibody levels to clinical outcome. The doses of immunoglobulin (Ig)G/kg/month were similar in both IVIG and SCIG groups. In 11 patients treated with IVIG, Spn antibody titres were ≥ 1·3 µg/ml to 99·4 ± 2·1% of the 14 serotypes at peak IVIG but decreased to 66·9 ± 19·8% at trough IVIG. Loss of Spn titres ≥ 1·3 µg/ml was most frequent for Spn serotypes 1, 4, 9V and 23. This correlated with lower Spn antibody titres to these serotypes at peak IVIG compared to the other serotypes. In 13 patients treated with SCIG, Spn antibody titres were protective to 58·2 ± 23·3% of the serotypes 3-5 days after infusion, similar to trough IVIG. Similarly, the Spn serotypes with the least protective percentages were the same as the ones observed in trough IVIG. There were no annualized serious bacterial infections (aSBI) in either group. However, there were significantly decreased annualized other infections (aOI) in the SCIG group compared to the IVIG-treated group, 0·8 ± 0·7 versus 2·2 ± 1·2 infections/patient/year (P = 0·004). Breakthrough aOI did not correlate with protective or higher serum Spn antibody titres.

Defense-in-depth by mucosally administered anti-HIV dimeric IgA2 and systemic IgG1 mAbs: complete protection of rhesus monkeys from mucosal SHIV challenge.

Although IgA is the most abundantly produced immunoglobulin in humans, its role in preventing HIV-1 acquisition, which occurs mostly via mucosal routes, remains unclear. In our passive mucosal immunizations of rhesus macaques (RMs), the anti-HIV-1 neutralizing monoclonal antibody (nmAb) HGN194, given either as dimeric IgA1 (dIgA1) or dIgA2 intrarectally (i.r.), protected 83% or 17% of the RMs against i.r. simian-human immunodeficiency virus (SHIV) challenge, respectively. Data from the RV144 trial implied that vaccine-induced plasma IgA counteracted the protective effector mechanisms of IgG1 with the same epitope specificity. We thus hypothesized that mucosal dIgA2 might diminish the protection provided by IgG1 mAbs targeting the same epitope. To test our hypothesis, we administered HGN194 IgG1 intravenously (i.v.) either alone or combined with i.r. HGN194 dIgA2. We enrolled SHIV-exposed, persistently aviremic RMs protected by previously administered nmAbs; RM anti-human IgG responses were undetectable. However, low-level SIV Gag-specific proliferative T-cell responses were found. These animals resemble HIV-exposed, uninfected humans, in which local and systemic cellular immune responses have been observed. HGN194 IgG1 and dIgA2 used alone and the combination of the two neutralized the challenge virus equally well in vitro. All RMs given only i.v. HGN194 IgG1 became infected. In contrast, all RMs given HGN194 IgG1+dIgA2 were completely protected against high-dose i.r. SHIV-1157ipEL-p challenge. These data imply that combining suboptimal defenses at the mucosal and systemic levels can completely prevent virus acquisition. Consequently, active vaccination should focus on defense-in-depth, a strategy that seeks to build up defensive fall-back positions well behind the fortified frontline.

The protective effects of IgM-enriched immunoglobulin and erythropoietin on the lung and small intestine tissues of rats with induced sepsis: biochemical and histopathological evaluation.

CONTEXT: Sepsis continues to be a significant problem for critical care patients. OBJECTIVE: To evaluate the protective effects of IgM-enriched immunoglobulin and erythropoietin on pulmonary and small intestine tissues in a rat model of intra-abdominal sepsis induced via the cecal ligation and puncture (CLP) method. MATERIALS AND METHODS: Male Sprague-Dawley rats were used. Control group (n = 6): surgical procedure was not performed. Laparotomy was only performed in the sham group (n = 6) and CLP was only performed in the sepsis (CLP) group (n = 30). After erythropoietin (2000 U/kg, intraperitoneal) was given in the sepsis + erythropoietin (CLP + EPO) group (n = 30), IgM-enriched immunoglobulin (600 mg/kg, intraperitoneal) was given in the sepsis + pentaglobin (CLP + PEN) group (n = 30), CLP was created. Intracardiac blood samples were collected for biochemical analysis; lung and small intestine tissue samples were removed for histopathological evaluation. RESULTS: Plasma TNF-α levels (pg/ml) were similar among CLP, CLP + EPO, and CLP + PEN groups (204.0 ± 52.4, 198.5 ± 17.3, and 214.6 ± 93.6, respectively). The CLP group had higher plasma IL-1ß levels (pg/ml) compared with CLP + EPO and CLP + PEN groups (325.1 ± 134.1, 164.3 ± 25.6, and 186.3 ± 26.0, respectively) (p < 0.05). Rats in CLP + EPO and CLP + PEN groups had abolished histopathologic appearance of lung and small intestine tissues compared with rats in the CLP group. DISCUSSION AND CONCLUSION: Our findings support the use of EPO and IgM-enriched immunoglobulin in the prevention of lung and small intestine injuries associated with sepsis.

Intravenous IgA complexed with antigen reduces primary antibody response to the antigen and anaphylaxis upon antigen re-exposure by inhibiting Th1 and Th2 activation in mice.

CONTEXT: Serum IgG, IgE and IgM have been shown to enhance the primary antibody responses upon exposure to the soluble antigens recognized by those antibodies. However, how IgA affects these responses remains unknown. OBJECTIVE: We investigated the effects of intravenously administered monoclonal IgA on the immune responses in mice. MATERIALS AND METHODS: DBA/1J mice were immunized with ovalbumin in the presence or absence of anti-ovalbumin monoclonal IgA. The Th1 and Th2 immune responses to ovalbumin and the anaphylaxis induced by re-exposure to ovalbumin were measured. RESULTS: IgA complexed with antigen attenuated the primary antibody responses to the antigen in mice, in contrast to IgG2b and IgE. The primary antibody responses, i.e. the de novo synthesis of anti-ovalbumin IgG2a, IgG1 and IgE in the serum, and the subsequent anaphylaxis induced with re-exposure to ovalbumin were reduced by the co-injection of anti-ovalbumin monoclonal IgA at ovalbumin immunization. The Th1, Th2 and Tr1 cytokines interferon-γ, interleukin-4 and interleukin-10, respectively, released from ovalbumin-restimulated cultured splenocytes collected from allergic mice were also reduced by the treatment. The induction of interferon-γ and interleukin-4 secretion by splenocytes from ovalbumin-immunized mice stimulated in vitro with ovalbumin was also significantly reduced by the antigen complexed with anti-ovalbumin IgA. CONCLUSION: These data suggest that the direct inhibition of Th1 and Th2 activation by anti-ovalbumin monoclonal IgA participates in the inhibition of the primary antibody responses. IgA plays important immunosuppressive roles under physiological and pathological conditions and is a promising candidate drug for the treatment of immune disorders.

Perioperative management of an IgA-deficient recipient of a double-lung transplant.

PURPOSE: When exposed in the perioperative period to blood components containing immunoglobulin (Ig)A IgA-sensitized IgA-deficient patients are at an increased risk of transfusion-associated anaphylaxis. We present the case of an IgA-deficient patient whose candidacy for double-lung transplantation was under review in the preoperative period. CLINICAL FEATURES: A 49-yr-old patient with end-stage chronic obstructive lung disease secondary to deficiencies in IgA and IgG subclasses was being assessed for double-lung transplantation. Early recognition of the ramifications of perioperative transfusion prompted consultation with the transfusion medicine service. This in turn facilitated specialized laboratory testing and the coordinated provision of appropriate blood products for the unpredictable date of transplantation. The theoretical systemic risks of a non-IgA-deficient graft on the sensitized IgA-deficient host were considered. To affirm the patient's candidacy for transplantation, he was ultimately challenged preoperatively with IgA-containing products in a controlled intensive-care setting. CONCLUSION: Through a multidisciplinary approach [corrected], a successful transplantation outcome was achieved in an IgA-deficient patient undergoing major surgery. Strategies to mitigate risk include the procurement and transfusion of IgA-deficient components, which may be challenging or untenable in emergent perioperative settings.

Preliminary studies on the development of IgA-loaded chitosan-dextran sulphate nanoparticles as a potential nasal delivery system for protein antigens.

This study describes the development of a biodegradable nanoparticulate system for the intranasal delivery of multiple proteins. Chitosan (CS)-dextran sulphate (DS) nanoparticles were developed and optimised for the incorporation of pertussis toxin (PTX) and a potential targeting ligand (immunoglobulin-A, IgA). In vitro characterization and in vivo uptake studies were performed for the evaluation of developed nanoparticles. The ratio of CS to DS, the order of mixing and pH of nanoparticle suspension were identified as important formulation factors governing the size and zeta potential of nanoparticles. An optimised CS-DS nanoparticle formulation prepared with the CS to DS weight ratio of 3 : 1 was used to load PTX and/or IgA. Entrapment efficiency of >90% was obtained for both. The in vivo uptake of IgA-loaded CS-DS nanoparticles in mice showed a preferential uptake of nanoparticles probably by nasal membranous or microfold cells following intranasal administration. The results of this study indicate the potential application of IgA-loaded CS-DS nanoparticles as a nasal vaccine delivery system.

Pentaglobin as an adjunct therapy in very low birthweight neonates with nosocomial sepsis.

OBJECTIVE: To evaluate the effect of pentaglobin treatment on clinical and laboratory parametres and the major morbidities in very low birthweight neonates with nosocomial sepsis before and after pentaglobin treatment. METHODS: The prospective interventional study was conducted from January 1 to December 31, 2010, at the neonatal intensive care unit (NICU) of the Bakirköy Dr. Sadi Konuk Training and Research Hospital, Istanbul, Turkey. Pentaglobin was initiated on the day of diagnosis of nosocomial sepsis to 13 pre-term neonates as a support therapy in addition to antibiotics; 5 ml/kg per day of pentaglobin was infused over a 4-hour period on 3 consecutive days. Clinical and laboratory parametres and major morbidities were recorded before and after pentaglobin treatment and compared using NCSS software. RESULTS: Of the total, 8 (66%) were females and 5 (40%) males. Following pentaglobin therapy, the immature-to-total neutrophil ratio and C-reactive protein levels were significantly decreased, and the capillary pH and base excess were significantly increased (p < 0.05). The axillary temperature, non-invasive blood pressure, haemoglobin, leukocyte, and thrombocyte values did not significantly differ before and after treatment (p > 0.05). Coagulase-negative staphylococci (n = 3; 23%), Klebsiella pneumoniae (n = 2; 15.3%), and Pseudomonas aeruginosa (n = 1; 7.7%) were identified in blood cultures. The presence of intraventricular haemorrhages, necrotising enterocolitis, periventricular leukomalacia, and patent ductus arteriosus was not changed following the treatment. Adverse effects and mortality were not observed during or after the therapy. CONCLUSION: Pentaglobin treatment of nosocomial sepsis could be used as an adjunct therapy without any adverse short-term reactions, even in very low birthweight pre-term infants.

Enhanced immune response against pertussis toxoid by IgA-loaded chitosan-dextran sulfate nanoparticles.

The objective of the present study was to evaluate immunological activities of chitosan-dextran sulfate (CS-DS) nanoparticle formulation of pertussis toxoid (PTXd) and its combination with a potential immunological adjuvant, immunoglobulin A (IgA). CS-DS nanoparticles were prepared using a complex coacervation (polyelectrolyte complexation) technique. CS-DS nanoparticle formulations with size and zeta potential in a range of 300-350 nm and +40-+55 mV, respectively, were obtained. An entrapment efficiency of more than 90% was obtained for pertussis toxin and IgA in CS-DS nanoparticles. All loaded nanoparticle formulations showed less than 20% of release within 24 h in in vitro release studies. The immunological evaluation of developed formulations in female Balb/c mice groups showed that the CS-DS nanoparticles formulations induced significantly higher serum IgG and IgG1 titers (p < 0.05) as compared with conventional alum-adjuvanted PTXd formulation administered by subcutaneous route. This study indicated the potential of CS-DS nanoparticles to be a simple and effective particulate delivery system with in-built immunological adjuvant property for acellular protein antigens. The study also revealed the potential important role of IgA-loaded CS-DS nanoparticles as a novel immunological adjuvant for vaccine delivery.