Immunological and molecular-biological studies on pathogenesis and treatments of intractable obits media

肺炎链球菌和流感嗜血杆菌是儿童急性中耳炎的主要致病菌。75.8%的菌株存在青霉素结合蛋白1a、2b和2x（PBP）突变，经PCR鉴定pbp 1a、pbp 2x和pbp 2b基因异常可分为7个基因型：（1）青霉素敏感的S. pbp基因无异常的肺炎链球菌（PSSP）（24.2%）;仅具有异常pbp 2x基因[gPISP（2x）]的肺炎（gPISP）分离株（26%），（iii）仅具有异常pbp 1a基因[gPISP（/a）]（0.1%）（iv）仅具有异常pbp 2b基因[gPISP（2b）] pbp 1a和pbp 2x基因异常的gPISP菌株（2.8%）; pbp 2x和pbp 2b基因异常的gPISP菌株（2.2%）; pbp基因异常率为38.5%。H.敏感株（MIC ≤ 1 pg/ml）占61.0%，中度敏感株37株（14.0%）， ...更多信息 耐药菌株MIC ≥ 4 pg/ml者66株（25.0%）。5株产TEM型β-内酰胺酶。fts 1基因突变3株（1.2%），gBLPACR：产β-内酰胺酶的阿莫西林-克拉维酸耐药; fts 1基因无突变2株（0.8%），gBLPAR：产β-内酰胺酶的氨苄西林耐药。根据PCR基因分型，172株（65.1%）菌株存在fts 1基因突变，但不产生β-内酰胺酶（gBLNAR：基因上不产生氨苄青霉素的β-内酰胺酶）。其中98株（37.1%）为可变区Ⅰ/Ⅱ组突变（Ⅰ/Ⅱ组gBLNAR），74株（28.0%）为高度突变区Ⅲ组突变（Ⅲ组gBLNAR）。其余87株（33.0%）为gBLNAS（基因上不产β-内酰胺酶的氨苄青霉素敏感株），fts 1基因和bla基因均未发生突变。第III组gBLNAR菌株对青霉素和头孢菌素均表现出耐药性。PBP基因突变H.流感不仅对氨苄青霉素耐药，而且对头孢菌素敏感性降低。H.在治疗上呼吸道感染性疾病时，应考虑到流感病毒，在2岁以下儿童中诱导有效的保护性免疫非常重要。在本研究中，我们评估了流感嗜血杆菌P6的母体免疫，以诱发针对P6的特异性抗体并将其转移给后代。我们用P6鼻内免疫母鼠，并研究了血清和乳汁中特异性抗体的诱导。并根据哺乳情况调查免疫母亲所产子代的特异性抗体，以评价免疫母亲母乳喂养的重要性。我们的研究结果强烈表明，母亲鼻内免疫P6将是一个有吸引力的战略，对NTHi感染在幼儿期。它可以在怀孕期间通过胎盘和出生后通过母乳提供保护性抗体。少

S.pneumoniae and H.influenzae have been major pathogens in acute otitis media of children. Almost 75.8% strains had mutation in their penicillin binding protein la, 2b and 2x (PBP) and they were classified into seven genotypic classes after PCR identification of abnormal pbp1a, pbp2x, and pbp2b genes: (i) penicillin-susceptible S. pneumoniae (PSSP) isolates with no abnormal pbp genes (24.2%), (ii) genotypic penicillin-intermediate S. pneumoniae (gPISP) isolates with only an abnormal pbp2x gene [gPISP (2x)] (26%), (iii) with only an abnormal pbp1a gene [gPISP (/a)](0.1%) (iv) with only an abnormal pbp2b gene [gPISP (2b)](2.2%) (V) gPISP isolates with abnormal pbp1a and pbp2x genes (2.8%), (vi) gPISP isolates with abnormal pbp2x and pbp2b genes (2.2%), and (vii) genotypic penicillin-resistant S. pneumoniae (gPRSP) isolates with three abnormal pbp genes (38.5%). H. influenzae isolates were divided into 61.0% susceptible strains (MIC less than or equal 1 pg/ml), 37 (14.0%) intermediately r … More esistant strains (MIC =2 μg/ml) and 66 (25.0%) resistant strains (MIC greater than or equal 4 pg/ml). Five strains produced TEM type β-lactamase. They were divided into 3 (1.2%) strains with mutations in fts1 gene (gBLPACR: genetically β-lactamase producing amoxicillin-clavulanate resistant) and 2 (0.8%) strains without mutations infts1 gene gBLPAR (genetically β-lactamase producing ampicillin resistant). According to PCR-based genotyping, 172 (65.1%) isolates had mutations in fts1 gene without producing β-lactamase (gBLNAR: genetically β-lactamase nonproducing ampicillin resistant). They were 98 (37.1%) strains with group I/II mutations in variable mutated region (Group 1/II gBLNAR) and 74 (28.0%) strains with group III mutations in highly mutated region (Group III gBLNAR). The rest of 87 (33.0%) isolate were gBLNAS (genetically β-lactamase non-producing ampicillin susceptible) strains with neither mutations in fts1 gene nor bla gene. The Group III gBLNAR strains showed resistance to both penicillin and cephalosporin. PBP gene mutated H. influenzae not only resistance to ampicillin but also had reduce susceptibility to cephalosporin. The high prevalence of gBLNAR strains of H. influenzae should be taken into account when treating the upper respiratory tract infectious diseases.It is very important to induce effective protective immunity among children younger than 2 years of age. In this study, we evaluated the maternal immunization of P6 of H.influenzae to evoke specific antibody to P6 and to transfer it to offspring. We intranasally immunized mother mice with P6 and investigated the induction of specific antibody in sera and breast milk. The specific antibody among offspring delivered from immunized mother was also investigated according to the nursing status to evaluate the importance of breast feedings by immunized mothers. Our findings strongly suggest that maternal intranasal immunization with P6 would be an attractive strategy against NTHi infections during early childhood. It can supply protective antibodies via transplacental during pregnancy and via breast milk after birth. Less