Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Curren...Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection(HAR)that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure,in which process the MHCⅡmolecule plays critical roles.Methods:Thus,we generate a 4-gene(GGTA1,CMAH,β4GalNT2,and CIITA)knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously.Results:We successfully obtained 4KO piglets with deficiency in all alleles of genes,and at cellular and tissue levels.Additionally,the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping.Piglets have survived for more than one year in the barrier,and also survived for more than 3 months in the conventional environment,suggesting that the piglets without MHCⅡcan be raised in the barrier and then gradually mated in the conventional environment.Conclusions:4KO piglets have lower immunogenicity,are safe in genomic level,and are easier to breed than the model with both MHCⅠandⅡdeletion.展开更多
Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic nerve.Still,it is unknown whether olfactory enshea...Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic nerve.Still,it is unknown whether olfactory ensheathing glia also have neuroprotective properties.Olfactory ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion cells.Therefore,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve crush.Olfactory ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive treatments.Anatomical and gene expression analyses were performed.Olfactory bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡmolecules.Allogeneically and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an epimembrane.In axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 days.In these retinas,microglial anatomical activation was higher than after optic nerve crush alone.In intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or immunosuppression.However,neuroprotection of axotomized retinal ganglion cells did not improve with these treatments.The different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables.展开更多
Objective:To investigate the prevalence of microbial antigenic components of circulating immune complexes amongst grades of CD4 T lymphocyte counts in HIV sero positive and seronegative participants.Methods:Polyethele...Objective:To investigate the prevalence of microbial antigenic components of circulating immune complexes amongst grades of CD4 T lymphocyte counts in HIV sero positive and seronegative participants.Methods:Polyethelene glycol(PEG-600) and buffering methods of precipitation and dissociation of immune complexes was used to generate immune solution from sera of 100 HIV sero-positive and 100 HIV sero-negative participants.These were categorized into 3 grades based on CD4 count:】 500 cell/mm,200-499 cell/mm3 and 【200 cell/mm3.The immune solutions were assayed using membrane based immunoassay and antibody titration, along side its unprocessed serum for detection of various microbial antigens and or antibodies. CD4 T cell counts were estimated using Patec Cyflow SL-3 Germany.Results:Antigenic component of immune complexes of various infectious agents was detected in 99 and 70 HIV seropositive and HIV sero-negative participants,respectively.In group A,there were 10 HIV positive participants,including 4(40.0%) had circulating immune complexes(CICs) due to Salmonella species only:1(10.0%) due to Salmonella-Plasmodium falciparum(P.falciparum),SalmonellaP. falciparum-HCV and P.falciparum antigens,respectively.In group B,45(45.4%) HIV seropositive participants with CICs had CD4 T lymphocyte count between 200-499 cells/mm^3.Out of these,20(44.4%) had CICs due to Salmonella species only:9(20%) due to Salmonella-P. falciparum.In group C,there were 44(44.4%) HIV sero-positive participants,including 3(6.8%) due to Salmonella species only:24(54.4%) due to Salmonella-P.falciparum:2(4.5%) due to P. falciparum only.Conclusions:In HIV sero-positive participants,presence of heterogeneity of Salmonella species-P.falciparum antigens was highly incriminated in CD4 count depletion but not homogeneity of malaria parasites antigens.Malaria parasites antigens only were incriminated in CD4^+ count depletion amongst HIV sero-negative participants.Before taking any decision on the management of HIV-1-positive individuals,their malaria and Salmonella paratyphi status should be assessed,but not malaria status alone.展开更多
Various opinions have been presented on the merits and demerits that breastfeeding gives for the allergic onset of the babies. In this report, we focused on whether food proteins eaten by mother mice and secreted into...Various opinions have been presented on the merits and demerits that breastfeeding gives for the allergic onset of the babies. In this report, we focused on whether food proteins eaten by mother mice and secreted into breast milk as IgA-immune complexes contribute to the allergy prevention through oral tolerance in infants who ingest the milk. BALB/c mice were divided into two groups;E-group fed only egg white proteins and M-group fed only cow’s milk proteins as a dietary protein source. After immunizing M-group infants fed their own mother’s milk with ovalbumin/alum, diarrhea associated with experimental Th2 intestinal inflammation was induced by oral administration of ovalbumin. The diarrhea was dramatically suppressed in E-group infants. Concomitantly, low level of serum anti-ovalbumin- and ovomucoid-IgG1 and IgE, suppression of IL-4 synthesis by spleen cells, and low incidence of anaphylactic death after intravenous injection of ovalbumin were observed preferentially in E-infants. Immune complexes of respective dietary proteins and IgA were found in the breast milk obtained from each group of mother. Oral administration of pseudo immune complex chemically synthesized with ovalbumin and monoclonal mouse IgA in advance effectively suppressed anti-ovalbumin-IgG1 synthesis in adult mice after immunization with ovalbumin. The tolerance induced by the pseudo immune complex of ovalbumin diminished spontaneously while mice did not take egg white proteins. Thus, immune tolerance and then prevention of allergic disorder against dietary proteins were acquired via breastfeeding by mothers feeding the relevant proteins, probably through the immune complexes of dietary proteins and sIgAs secreted into breast milk.展开更多
When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,howeve...When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,however,Arthus reaction was significantly inhibited.OA showed markedly suppressive effects on reversible passive Arthus reaction and leukocyte migratory response.It could significantly stabilize erythrocyte membrane,inhibit the swelling of the rat's hind paw induced by in- jecting mycostatin,reduce the acid phosphatase content in the inflammatory exudate,suppress the syn- thesis or release of PGE,histamine,LTB4 and kinin,and the phlogistic action of PGE_2,histamine,5- HT and kinin.In addition,it could decrease the content of malonyldialdehyde (MDA) in hepatic tissue of alcohol-intoxicated mice,and increase the activity of catalase (CAT) in hepatic tissue of mice.OA had no apparent effect on the activity of super-oxide dismutase (SOD) in rat serum,on the content of immune complex in serum of rat with Arthus reaction,on the phagocytosis of monocytc-macrophage system,on the clearance of enzyme-containing immune complex by macrophage,or on the activity of total complement.展开更多
OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric an...OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P展开更多
The etiology of Meniere disease (MD) is unknown. Among the several factors which can provoke the disease is a pathological immune response. Objective: To investigate whether MD is due to a pathological immune reaction...The etiology of Meniere disease (MD) is unknown. Among the several factors which can provoke the disease is a pathological immune response. Objective: To investigate whether MD is due to a pathological immune reaction. Materials and methods: Immunological assay (IA) was evaluated in a consecutive study on 159 patients with MD (mean age 47.8. years) and the results compared with those from 26 patients operated on because of vestibular schwannoma (VS, mean age 54.1 years), who served as a control group. In cases of MD, transtympanic electrocochleography (ECoG) and hearing threshold were measured. Results: The average hearing level (HL) in the affected ears of patients with MD was 30 dB. Evidence of abnormal plasma protein pattern was found in 127 MD patients (80%). Elevations were found in β1-globulin (54.5%), β2-globulin (26.5%), a2-globulin (34.3%), g-globulin (17.3%), complement (CH100, 36.4%) and antinuclear antibodies (ANA, 43.4%). The onset of the disease did not correlate with the level of the plasma protein neither with the level of IgG titers. Conclusion: Elevated certain plasma proteins in patients with Meniere’s disease could be a sign that Meniere’s disease is a consequence of pathological immune reaction.展开更多
BACKGROUND Anti-glomerular basement membrane(GBM)disease is a rare rapidly progressive glomerulonephritis,frequently associated with alveolar hemorrhage in the lungs and involving the kidney by crescentic glomerulonep...BACKGROUND Anti-glomerular basement membrane(GBM)disease is a rare rapidly progressive glomerulonephritis,frequently associated with alveolar hemorrhage in the lungs and involving the kidney by crescentic glomerulonephritis.It has been described in association with other glomerulonephritides[such as anti-neutrophilic antibody(ANCA)-glomerulonephritis,membranous nephropathy,and immunoglobulin(Ig)A nephropathy].CASE SUMMARY Herein we present an unusual case of concurrent anti-GBM disease,ANCAassociated crescentic glomerulonephritis and diffuse proliferative immune complex mediated glomerulonephritis with predominant staining for IgA and C3 by immunofluorescence.The patient is a 46-year-old Caucasian male who presented to the emergency department with acute onset of flank pain and was found to have high serum creatinine levels of 15 mg/dL,proteinuria,and hematuria.He rapidly deteriorated and became anuric.He was found to have high anti-GBM antibodies titers(151 units)and high anti-neutrophil cytoplasmic-ANCA.Despite prompt and early treatment,the patient’s condition worsened,and he succumbed to his illness.CONCLUSION Our case emphasizes the importance of a renal biopsy in anti-GBM disease,even in the presence of positive serum anti-GBM antibodies,to identify other potential causes of rapidly progressive glomerulonephritis.The challenge in treating such cases lies in the different therapy modalities.展开更多
In order to study FcαRⅠ mediated phagocytosis of IgA immune complexes by U937 cells, antigen 8.9NIP/BSA was labeled with FITC and reacted with anti-NIP IgA or anti-NIP IgG antibody to form immune complexes (ICs). Th...In order to study FcαRⅠ mediated phagocytosis of IgA immune complexes by U937 cells, antigen 8.9NIP/BSA was labeled with FITC and reacted with anti-NIP IgA or anti-NIP IgG antibody to form immune complexes (ICs). They were then incubated with phorbol 12-myristate 13-acetate (PMA) stimulated U937 cells.The phagocytosed ICs were quantified by flow cytometry. The results was that the expression of FcαRⅠ on U937 cells was higher than that of FcγRⅠ, FcγRⅡ and FcγRⅢ. After stimulation by PMA, expression of FcαRⅠ on U937 cells was markedly upregulated and the phagocytosis of IgA ICs was enhanced. FcαRⅠ mediated specific IgA phagocytosis was stronger than FcγRⅠ and FcγRⅡ mediated IgG phagocytosis. Complement receptors, CR1 and CR3, enhanced U937 cell phagocytosis of IgA ICs. It concludes that FcαRⅠ mediated strong phagocytosis of IgA ICs.展开更多
基金National Key Research and Development Program,Grant/Award Number:2019YFA0903800,2021YFA0805701,2021YFA0805905 and 2022YFA1103603CAS Project for Young Scientists in Basic Research,Grant/Award Number:YSBR-012+2 种基金STI 2030-Major Project,Grant/Award Number:2023ZD0407503National Natural Science Foundation of China,Grant/Award Number:32071456 and 82241224Strategic Priority Research Program of the Chinese Academy of Sciences,Grant/Award Number:XDA16030000。
文摘Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection(HAR)that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure,in which process the MHCⅡmolecule plays critical roles.Methods:Thus,we generate a 4-gene(GGTA1,CMAH,β4GalNT2,and CIITA)knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously.Results:We successfully obtained 4KO piglets with deficiency in all alleles of genes,and at cellular and tissue levels.Additionally,the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping.Piglets have survived for more than one year in the barrier,and also survived for more than 3 months in the conventional environment,suggesting that the piglets without MHCⅡcan be raised in the barrier and then gradually mated in the conventional environment.Conclusions:4KO piglets have lower immunogenicity,are safe in genomic level,and are easier to breed than the model with both MHCⅠandⅡdeletion.
基金supported by the Spanish Ministry of Economy and Competitiveness,No.PID2019-106498GB-I00(to MVS)the Instituto de Salud CarlosⅢ,Fondo Europeo de Desarrollo Regional“Una manera de hacer Europa”,No.PI19/00071(to MAB)+1 种基金Ministerio de Ciencia e Innovación Project,No.SAF2017-82736-C2-1-R(to MTMF)in Universidad Autónoma de MadridFundación Universidad Francisco de Vitoria(to JS)。
文摘Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic nerve.Still,it is unknown whether olfactory ensheathing glia also have neuroprotective properties.Olfactory ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion cells.Therefore,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve crush.Olfactory ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive treatments.Anatomical and gene expression analyses were performed.Olfactory bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡmolecules.Allogeneically and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an epimembrane.In axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 days.In these retinas,microglial anatomical activation was higher than after optic nerve crush alone.In intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or immunosuppression.However,neuroprotection of axotomized retinal ganglion cells did not improve with these treatments.The different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables.
文摘Objective:To investigate the prevalence of microbial antigenic components of circulating immune complexes amongst grades of CD4 T lymphocyte counts in HIV sero positive and seronegative participants.Methods:Polyethelene glycol(PEG-600) and buffering methods of precipitation and dissociation of immune complexes was used to generate immune solution from sera of 100 HIV sero-positive and 100 HIV sero-negative participants.These were categorized into 3 grades based on CD4 count:】 500 cell/mm,200-499 cell/mm3 and 【200 cell/mm3.The immune solutions were assayed using membrane based immunoassay and antibody titration, along side its unprocessed serum for detection of various microbial antigens and or antibodies. CD4 T cell counts were estimated using Patec Cyflow SL-3 Germany.Results:Antigenic component of immune complexes of various infectious agents was detected in 99 and 70 HIV seropositive and HIV sero-negative participants,respectively.In group A,there were 10 HIV positive participants,including 4(40.0%) had circulating immune complexes(CICs) due to Salmonella species only:1(10.0%) due to Salmonella-Plasmodium falciparum(P.falciparum),SalmonellaP. falciparum-HCV and P.falciparum antigens,respectively.In group B,45(45.4%) HIV seropositive participants with CICs had CD4 T lymphocyte count between 200-499 cells/mm^3.Out of these,20(44.4%) had CICs due to Salmonella species only:9(20%) due to Salmonella-P. falciparum.In group C,there were 44(44.4%) HIV sero-positive participants,including 3(6.8%) due to Salmonella species only:24(54.4%) due to Salmonella-P.falciparum:2(4.5%) due to P. falciparum only.Conclusions:In HIV sero-positive participants,presence of heterogeneity of Salmonella species-P.falciparum antigens was highly incriminated in CD4 count depletion but not homogeneity of malaria parasites antigens.Malaria parasites antigens only were incriminated in CD4^+ count depletion amongst HIV sero-negative participants.Before taking any decision on the management of HIV-1-positive individuals,their malaria and Salmonella paratyphi status should be assessed,but not malaria status alone.
文摘Various opinions have been presented on the merits and demerits that breastfeeding gives for the allergic onset of the babies. In this report, we focused on whether food proteins eaten by mother mice and secreted into breast milk as IgA-immune complexes contribute to the allergy prevention through oral tolerance in infants who ingest the milk. BALB/c mice were divided into two groups;E-group fed only egg white proteins and M-group fed only cow’s milk proteins as a dietary protein source. After immunizing M-group infants fed their own mother’s milk with ovalbumin/alum, diarrhea associated with experimental Th2 intestinal inflammation was induced by oral administration of ovalbumin. The diarrhea was dramatically suppressed in E-group infants. Concomitantly, low level of serum anti-ovalbumin- and ovomucoid-IgG1 and IgE, suppression of IL-4 synthesis by spleen cells, and low incidence of anaphylactic death after intravenous injection of ovalbumin were observed preferentially in E-infants. Immune complexes of respective dietary proteins and IgA were found in the breast milk obtained from each group of mother. Oral administration of pseudo immune complex chemically synthesized with ovalbumin and monoclonal mouse IgA in advance effectively suppressed anti-ovalbumin-IgG1 synthesis in adult mice after immunization with ovalbumin. The tolerance induced by the pseudo immune complex of ovalbumin diminished spontaneously while mice did not take egg white proteins. Thus, immune tolerance and then prevention of allergic disorder against dietary proteins were acquired via breastfeeding by mothers feeding the relevant proteins, probably through the immune complexes of dietary proteins and sIgAs secreted into breast milk.
文摘When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,however,Arthus reaction was significantly inhibited.OA showed markedly suppressive effects on reversible passive Arthus reaction and leukocyte migratory response.It could significantly stabilize erythrocyte membrane,inhibit the swelling of the rat's hind paw induced by in- jecting mycostatin,reduce the acid phosphatase content in the inflammatory exudate,suppress the syn- thesis or release of PGE,histamine,LTB4 and kinin,and the phlogistic action of PGE_2,histamine,5- HT and kinin.In addition,it could decrease the content of malonyldialdehyde (MDA) in hepatic tissue of alcohol-intoxicated mice,and increase the activity of catalase (CAT) in hepatic tissue of mice.OA had no apparent effect on the activity of super-oxide dismutase (SOD) in rat serum,on the content of immune complex in serum of rat with Arthus reaction,on the phagocytosis of monocytc-macrophage system,on the clearance of enzyme-containing immune complex by macrophage,or on the activity of total complement.
文摘OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P
文摘The etiology of Meniere disease (MD) is unknown. Among the several factors which can provoke the disease is a pathological immune response. Objective: To investigate whether MD is due to a pathological immune reaction. Materials and methods: Immunological assay (IA) was evaluated in a consecutive study on 159 patients with MD (mean age 47.8. years) and the results compared with those from 26 patients operated on because of vestibular schwannoma (VS, mean age 54.1 years), who served as a control group. In cases of MD, transtympanic electrocochleography (ECoG) and hearing threshold were measured. Results: The average hearing level (HL) in the affected ears of patients with MD was 30 dB. Evidence of abnormal plasma protein pattern was found in 127 MD patients (80%). Elevations were found in β1-globulin (54.5%), β2-globulin (26.5%), a2-globulin (34.3%), g-globulin (17.3%), complement (CH100, 36.4%) and antinuclear antibodies (ANA, 43.4%). The onset of the disease did not correlate with the level of the plasma protein neither with the level of IgG titers. Conclusion: Elevated certain plasma proteins in patients with Meniere’s disease could be a sign that Meniere’s disease is a consequence of pathological immune reaction.
文摘BACKGROUND Anti-glomerular basement membrane(GBM)disease is a rare rapidly progressive glomerulonephritis,frequently associated with alveolar hemorrhage in the lungs and involving the kidney by crescentic glomerulonephritis.It has been described in association with other glomerulonephritides[such as anti-neutrophilic antibody(ANCA)-glomerulonephritis,membranous nephropathy,and immunoglobulin(Ig)A nephropathy].CASE SUMMARY Herein we present an unusual case of concurrent anti-GBM disease,ANCAassociated crescentic glomerulonephritis and diffuse proliferative immune complex mediated glomerulonephritis with predominant staining for IgA and C3 by immunofluorescence.The patient is a 46-year-old Caucasian male who presented to the emergency department with acute onset of flank pain and was found to have high serum creatinine levels of 15 mg/dL,proteinuria,and hematuria.He rapidly deteriorated and became anuric.He was found to have high anti-GBM antibodies titers(151 units)and high anti-neutrophil cytoplasmic-ANCA.Despite prompt and early treatment,the patient’s condition worsened,and he succumbed to his illness.CONCLUSION Our case emphasizes the importance of a renal biopsy in anti-GBM disease,even in the presence of positive serum anti-GBM antibodies,to identify other potential causes of rapidly progressive glomerulonephritis.The challenge in treating such cases lies in the different therapy modalities.
文摘In order to study FcαRⅠ mediated phagocytosis of IgA immune complexes by U937 cells, antigen 8.9NIP/BSA was labeled with FITC and reacted with anti-NIP IgA or anti-NIP IgG antibody to form immune complexes (ICs). They were then incubated with phorbol 12-myristate 13-acetate (PMA) stimulated U937 cells.The phagocytosed ICs were quantified by flow cytometry. The results was that the expression of FcαRⅠ on U937 cells was higher than that of FcγRⅠ, FcγRⅡ and FcγRⅢ. After stimulation by PMA, expression of FcαRⅠ on U937 cells was markedly upregulated and the phagocytosis of IgA ICs was enhanced. FcαRⅠ mediated specific IgA phagocytosis was stronger than FcγRⅠ and FcγRⅡ mediated IgG phagocytosis. Complement receptors, CR1 and CR3, enhanced U937 cell phagocytosis of IgA ICs. It concludes that FcαRⅠ mediated strong phagocytosis of IgA ICs.