Efficacy of Combined Desensitization Therapy Based on Protein A Immunoadsorption on Anti-human Leukocyte Antigen Antibodies in Sensitized Kidney Transplant Recipients: A Retrospective Study.

Background and objectives Protein A immunoadsorption (PA-IA) therapy is an immunoglobulin selective apheresis for pre-transplantation desensitization therapy and treatment of post-transplantation antibody-mediated rejection. There is no unified protocol for the timing of PA-IA therapy or its combination with other drug therapy. This study aimed to investigate and analyze the clearance effects of desensitization therapy on human leukocyte antigen (HLA) antibodies to provide a reference for the formulation of clinical desensitization therapy regimens. Materials and methods Overall, 27 kidney transplant recipients who received preoperative/postoperative desensitization therapy based on PA-IA therapy in combination with drug therapy were enrolled. The pre-treatment mean fluorescence intensity (MFI) of 1324 human leukocyte antigen (HLA) antibody specificities (MFI >2000) and the post-treatment MFI of the corresponding antibody specificities (after one, four, seven, and 10 sessions) were recorded to analyze the changes in antibody level reduction for the different antibody classes and MFI ranges. Results After 10 sessions of PA-IA therapy, the MFI of class I antibodies decreased from 8298.56 to 3196.15 (reduction of 66.80%), while the MFI of class II antibodies decreased from 13,521.09 to 2773.29 (reduction of 71.14%). The pre-treatment level of class II antibodies was significantly higher than that of class I antibodies (p<0.001), whereas the post-treatment levels of class I and II antibodies were comparable (p>0.05). The clearance effects of PA-IA therapy were greater for strongly positive (MFI>10,000) class II antibodies than for strongly positive class I antibodies, showing a reduction of 62.59% (25.17% to 91.04%) and 45.13% (32.70% to 73.94%), respectively (p=0.015). Conclusions We confirmed the removal efficacy of PA-IA for HLA antibodies. The removal efficacy of class II antibodies on PA-IA is not inferior to that of class I. Under an adequate number of treatment sessions, the clearance effect of PA-IA therapy for strongly positive class II antibodies may be greater than that for strongly positive class I antibodies.

Protein A immunoadsorption for the treatment of refractory anti-N-methyl-d-aspartate receptor encephalitis: A single-center prospective study.

OBJECTIVE: The aim of this study was to evaluate the efficacy and safety of protein A immunoadsorption (IA) for anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis resistant to intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG). METHODS: We prospectively evaluated patients with refractory anti-NMDAR encephalitis, treated with protein A IA. Demographic data, clinical characteristics, modified Rankin Score (mRS), and anti-NMDAR antibodies were documented before and after IA and at follow-up. Clinical improvement was defined as a decrease of mRS ≥1. Adverse events were recorded throughout the study. RESULTS: Ten patients with mRS ≥3 were enrolled and treated with protein A IA; treatment was performed for an average of 5.2 times per patient. Among the nine patients with positive serum anti-NMDAR, the titer decreased in seven patients, of which two became negative. The cerebrospinal fluid (CSF) anti-NMDAR titer decreased in all patients, and one became negative. Anti-NMDAR levels were tested in two patients at follow-up and found to have declined continuously. All patients exhibited clinical improvement with a mRS decline ≥1 after IA treatment (median mRS: 5.0 [range, 3.0-5.0] vs. 4.0 [range, 2.0-4.0], p = 0.014), and the median mRS decreased to 1.0 (range, 0-3.0) at follow-up. After IA, all patients exhibited accelerated recovery. No adverse events were observed during IA treatment. CONCLUSION: Protein A IA may be effective for treating IVMP/IVIG-resistant anti-NMDAR encephalitis and well tolerated. It is necessary to initiate larger-scale prospective controlled studies to validate the efficacy and safety of protein A IA in anti-NMDAR encephalitis.

Protein A Immunoadsorption Relieves Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy after Unsuccessful Methylprednisolone Treatment.

BACKGROUND: Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy (GFAP-A) is a recently defined autoimmune inflammatory disease of the central nervous system in which GFAP IgG is present in the cerebrospinal fluid (CSF). Its primary clinical manifestation is meningoencephalitis, and it usually responds well to corticosteroids. Herein, we report a case of a patient with GFAP-A with initial symptoms of psychological and cognitive impairment, which did not respond to high-dose methylprednisolone therapy but was successfully treated with protein A immunoadsorption (PAIA) therapy. METHODS: GFAP IgG was detected by indirect immunofluorescence assay. The patient's data were analyzed retrospectively. RESULTS: A 48-year-old man presented with anxiety, depression, cognitive decline, tremor, gait disturbance, and fecal and urine incontinence. Autoimmune GFAP-A was diagnosed based on the following: (1) T2-weighted and fluid-attenuated inversion recovery MRI findings of hypersensitive lesions in the subcortical and deep white matter of the brain, with multiple longitudinally extensive lesions in the cervical and chest regions of the spinal cord, and (2) high levels of GFAP IgG in the CSF. Clinical symptoms and abnormalities detected on neuroimaging worsened after administration of high-dose intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG) but improved significantly after PAIA therapy. CONCLUSION: Psychological impairment can be the first sign of autoimmune GFAP-A. PAIA might be an effective treatment for patients with GFAP-A who respond poorly to conventional IVMP and IVIG therapy.

Rescue immunoadsorption treatment for neuromyelitis optica spectrum disorder attacks unresponsive to intravenous methylprednisolone.

We aimed to evaluate the value of immunoadsorption (IA) treatment after the failure of intravenous methylprednisolone (IVMP) therapy for neuromyelitis optica spectrum disorder (NMOSD). Sixty-one NMOSD attacks unresponsive to IVMP were included: 22 patients received rescue IA (IVMP+IA), 24 underwent rescue plasma exchange (PE) (IVMP+PE), and 21 received no further rescue therapy (IVMP alone). The improvement frequencies were higher in the IVMP+IA and IVMP+PE groups than in the IVMP-alone group (P = 0.024). The effective period for IA treatment may be longer than previously thought. IA treatment for IVMP-resistant NMOSD attacks was effective and comparable to PE treatment.

Treatment of Severe Japanese Encephalitis Complicated With Hashimoto's Thyroiditis and Guillain-Barré Syndrome With Protein A Immunoadsorption: A Case Report.

A severely comatose female patient was diagnosed with Japanese encephalitis (JE). Her condition was complicated by Hashimoto's thyroiditis (HT) and Guillain-Barré syndrome (GBS). After antiviral, glucocorticoid, and immunoglobulin treatment, the patient's consciousness was restored, and she could breathe spontaneously. Following this, new-onset, primarily demyelinating GBS developed, which progressed to demyelination combined with axonal injury. The patient was switched to protein A immunoadsorption (PAIA) therapy, and her Hughes score decreased rapidly, from 4 to 1 after 6 months. This patient is the first to receive PAIA combined with an antiviral-glucocorticoid-immunoglobulin regimen to treat encephalitis, meningitis, HT, and GBS caused by JE infection, thereby reflecting the importance of clinical application of PAIA in the treatment of immunological complications of JE.

Soluble expression of a strong thrombolytic pro-urokinase mutant in Escherichia coli.

A recombinant pro-urokinase mutant GZ5-sPA was successfully constructed by fusion of a high fibrin-affinity fragment GZ5 to the N-terminus of the serine protease domain of pro-urokinase (sPA). The fragment GZ5 contains a tetrapeptide GPRP and a tripeptide RGD, and was synthesized in bacterial preferred expressing codons. The mutant was then fused to the C-terminus of maltose binding protein (MBP) carried by pMAL-C2x vector, and expressed in Escherichia coli strain Origami (DE3). The produced fusion protein was highly soluble in the cytoplasm of the bacteria. After being cleaved with PreScission Protease to remove MBP tag, GZ5-sPA showed a molecular weight of 31 kDa on SDS-PAGE. GZ5-sPA maintained the same epitope as wild-type pro-urokinase and possessed a thrombolytic activity three times higher than standard urokinase did after being activated as two-chain form. The results could be a clue to other complicated heterogenous proteins similar to pro-urokinase.