SEARCH · PubMed Health

Results for “Class”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources

PubMed1999

Evidence for healing of Class II and Class III furcations 24 months after guided tissue regeneration therapy: digital subtraction and clinical measurements.

BACKGROUND: The aim of this study was to compare bone regeneration as assessed by subtraction radiography with clinical attachment measurements 24 months after regenerative surgery. METHODS: In 24 patients with advanced periodontitis, 34 Class II and 10 Class III furcations were treated by guided tissue regeneration using expanded polytetrafluoroethylene (n = 18) or bioabsorbable barriers (n = 26). Clinical parameters were assessed and 40 pairs of standardized radiographs were taken before and 24 months after surgery. Bony gain within furcations was assessed using subtraction analysis. RESULTS: In Class II furcations, statistically significant (P <0.001) vertical (CAL-V: 1.06+/-1.56 mm) and horizontal (CAL-H: 2.05+/-1.24 mm) attachment gain was observed 24 months postsurgically. Within Class III defects CAL-V gain was assessed 1.78+/-1.43 mm (P <0.005). CAL-H gain in buccal and lingual Class II furcations was explained by the relative density gain, baseline CAL-H, gingival index (GI) reduction, and individual patients (P <0.001) whereas, multiple regression analysis failed to show a relation between CAL-H gain and any of the subtraction parameters for interproximal furcations. Vertical attachment gain in interproximal sites was explained by net bony area gain (subtraction), PD and GI reduction, baseline CAL-V, defect type, smoking, and individual patients (P<0.001). CONCLUSIONS: There was a statistically significant correlation between clinical and radiographic improvements within furcation defects. However, this correlation was modulated by other factors such as baseline CAL-V or CAL-H, PD and GI reduction, or smoking. The relative density gain seemed to sufficiently describe bony changes related to clinical changes within buccal and lingual furcations, whereas bone area gain suitably described bony changes in interproximal Class II and III furcations.

Absorbable Implants↗

PubMed2003

Antimicrobial resistance markers of class 1 and class 2 integron-bearing Escherichia coli from irrigation water and sediments.

Municipal and agricultural pollution affects the Rio Grande, a river that separates the United States from Mexico. Three hundred and twenty-two Escherichia coli isolates were examined for multiple antibiotic resistance phenotypes and the prevalence of class 1 and class 2 integron sequences. Thirty-two (10%) of the isolates were resistant to multiple antibiotics. Four (13%) of these isolates contained class 1-specific integron sequences; one isolate contained class 2 integron-specific sequences. Sequencing showed that the class 1 integron-bearing strain contained two distinct gene cassettes, sat-1 and aadA. Although three of the four class 1 integron-bearing strains harbored the aadA sequence, none of the strains was phenotypically resistant to streptomycin. These results suggest that integron-bearing E. coli strains can be present in contaminated irrigation canals and that these isolates may not express these resistance markers.

Anti-Bacterial Agents↗

PubMed1988

Property of class I H-2 alloantigen-reactive Lyt-2+ helper T cell subset. Abrogation of its proliferative and IL-2-producing capacities by intravenous injection of class I H-2-disparate allogeneic cells.

The present study investigates the distinctiveness of Class I H-2 alloantigen-reactive Lyt-2+ helper/proliferative T cell subset in the aspect of tolerance induction. Primary mixed lymphocyte reactions (MLR) revealed that Lyt-2+ and L3T4+ T cell subsets from C57BL/6 (B6) mice were exclusively capable of responding to class I H-2 [B6-C-H-2bm1 (bm1)]- and class II H-2 [B6-C-H-2bm12 (bm12)]-alloantigens, respectively. Anti-bm12 MLR was not affected by i.v. injection of bm12 spleen cells into recipient B6 mice. In contrast, a single i.v. administration of bm1 spleen cells into B6 mice resulted in the abrogation of the capacity of recipient B6 spleen and lymph node cells to give anti-bm1 MLR. This suppression was bm1 alloantigen-specific, since lymphoid cells from B6 mice i.v. presensitized with bm1 cells exhibited comparable anti-bm12 primary MLR to that obtained by normal B6 lymphoid cells. Such tolerance was rapidly (24 h after the i.v. injection of bm1 cells) inducible and lasting for at shortest 3 wk. Addition of lymphoid cells from anti-bm1-tolerant B6 mice to cultures of normal B6 lymphoid cells did not suppress the proliferative responses of the latter cells, indicating that the tolerance is not due to the induction of suppressor cells but attributed to the elimination or functional impairment of anti-bm1 proliferative clones. The tolerance was also demonstrated by the failure of tolerant lymphoid cells to produce IL-2. It was, however, found that anti-bm1 CTL responses were generated by tolerant lymphoid cells which were unable to induce the anti-bm1 MLR nor to produce detectable level of IL-2. These results demonstrate that class I H-2 alloantigen-reactive Lyt-2+ Th cell subset exhibits a distinct property which is expressed by neither Lyt-2+ CTL directed to class I H-2 nor L3T4+ Th cells to class II H-2 alloantigens.

Animals↗

PubMed1987

Frequency analysis of class I MHC-reactive Lyt-2+ and class II MHC-reactive L3T4+ IL 2-secreting T lymphocytes.

The reactivity of Lyt-2+ or L3T4+ T cells stimulated with either mutant class I or class II MHC alloantigens was studied. Whereas stimulation with class I MHC antigens induced only Lyt-2+ T cells to proliferate and to secrete IL 2, stimulation with class II MHC alloantigens induced L3T4+ but not Lyt-2+ T cells. When the frequencies of precursors of IL 2-secreting T lymphocytes (IL 2TL-p) were determined by limiting dilution analyses, class I MHC-reactive Lyt-2+ T cells displayed frequencies (f = 1/200) as high in magnitude as those within class II MHC-reactive L3T4+ (f = 1/100). Clonally developing IL 2TL of either T cell subset were antigen-specific, as shown in split-culture experiments. Whereas L3T4+ helper TL could be induced to specific IL 2 secretion over a long time period (days 3 to 9), Lyt-2+ TL showed a marked time optimal on day 4; thereafter, the number of TL colonies inducible to secrete IL 2 decreased steadily. IL 2 production and IL 2TL-p frequencies of unseparated T responder cells were not the numerical superposition of the two individual T cell subsets (Lyt-2+ + L3T4+); the latter finding is likely to reflect regulatory influences of Lyt-2+ T cells on IL 2-secreting L3T4+ T cells.

Animals↗

PubMed1988

Identification of T cell subsets and class I and class II antigen expression in islet grafts and pancreatic islets of diabetic BioBreeding/Worcester rats.

The BioBreeding/Worcester (BB/Wor) rat develops a spontaneous disorder that closely resembles human insulin-dependent (Type I) diabetes mellitus. The syndrome is preceded by lymphocytic insulitis that destroys pancreatic beta cells. The morphologic features of the spontaneous insulitis lesions are also observed within islets transplanted beneath the renal capsule of diabetes-prone and diabetic animals. This study reports the results of experiments in which immunohistochemical techniques were used to characterize the phenotype of the infiltrating mononuclear cells and detect the expression of class I and class II MHC antigens in native islets and islet transplants in diabetic and diabetes-prone BB/Wor rats. The infiltrates within native pancreatic islets and islet grafts were comprised predominantly of Ia+ cells (dendritic cells and macrophages) CD4+ cells (helper/inducer lymphocytes and macrophages), CD5+ (pan-T) cells and smaller numbers of CD8+ (cytotoxic/suppressor and NK) cells. Pancreatic and graft insulitis were accompanied by markedly enhanced class I antigen expression on islet and exocrine cells. Class II (Ia) antigens were not detected on normal islet cells, islets undergoing insulitis or on islet transplants subjected to immune attack. In islet grafts stained with polymorphic MAbs that distinguish Ia antigens of donor and host origin, Ia antigen expression was limited to infiltrating dendritic cells and macrophages of host origin. It is concluded that the phenotypes of infiltrating mononuclear cells that comprise the insulitis lesion in spontaneous BB/Wor diabetes, and the inflammatory attack on islets transplanted into diabetic BB/Wor rats are the same, that pancreatic islet and graft insulitis occur in the presence of enhanced class I antigen expression but in the absence of class II antigen expression, and that infiltrating Ia+ cells within islet grafts are exclusively of recipient (BB/Wor) origin and may explain the initiation of immune insulitis within grafts derived from donors of incompatible MHC.

Animals↗

PubMed1987

Lack of expression of HLA [corrected] class I and class II molecules on the human oocyte.

The expression of histocompatibility leukocyte antigen (HLA) class I and class II antigens on human oocytes was investigated by the indirect immunofluorescence assay using well-defined monoclonal antibodies. Oocytes were obtained from an in vitro fertilization program or were studied on frozen sections from human ovaries. Neither HLA class I, beta 2-microglobulin, nor HLA class II molecules were detected on cultured oocytes or frozen sections. The zona pellucida also lacked these antigens, but granulosa cells expressed HLA class I molecules. Our results also indicate the presence of certain types of class II molecules on granulosa cells. The present experiments demonstrate that the human oocyte belongs to those few cell types in the human body which are devoid of both types of HLA molecules.

Antibodies, Monoclonal↗

PubMed1986

[Studies on HLA-class I and class II antigen expression in cultured choriocarcinoma cell lines].

Eight choriocarcinoma cell lines (Two SCH and IMa, were established from non-gestational choriocarcinoma and the other six BeWo, JaR, JEG-3, GCH-1, NUC-1, and HCCM-5, were from gestational one) were investigated for HLA-Class I and Class II antigen expression by the immunofluorescence method using rabbit anti HLA-ABC serum, and by a radioimmunoassay inhibition best using monoclonal antibodies (W6/32: anti HLA-ABC, 7B6: anti HLA-Class II, and D1-4-10: anti HLA-DR). With respect to HLA-Class I antigen expression, only non-gestational SCH (gastric origin) showed a clear positive finding. The other non-gestational IMa (ovarian origin) was negative. Cell lines from gestational choriocarcinoma showed a slightly positive finding (negative by immunofluorescence but slightly positive by inhibition test), except for JaR which was negative. All cell lines examined in the present study were negative for HLA-Class II antigen. The present results show that the majority of the gestational choriocarcinoma cell lines may express very slight HLA-Class I antigens.

Cell Line↗

PubMed1985

Evidence for the role of class I and class II HLA antigens in the lytic function of a cloned line of human natural killer cells.

Monoclonal antibodies with specificity for HLA class I and class II antigens were generated which either inhibit or enhance the lytic activity of a cloned line of human NK cells. These antibodies were obtained from a fusion with spleen cells from mice immunized with NK clone 3.3. They affect the lytic function of that clone at the level of the killer cell; additional evidence suggests that the effect takes place during an early stage of lysis. Immunoprecipitation and cross-clearing experiments using MHC antibodies of known specificity demonstrate the reactivity of mAbs 131 and 164 with HLA class I antigens and mAbs 210 and 273 with HLA class II antigens. Binding studies indicate that these antibodies are probably recognizing nonpolymorphic MHC determinants. Although these antibodies bind to other NK effector cells tested, they have no effect on the lytic function of these bulk NK populations. Preliminary studies, however, indicate that they do affect the NK activity of a proportion of the clones within these bulk populations. To further assess the potential role of HLA gene products in the lytic function of NK3.3, several well-defined anti-MHC antibodies were tested for their effects on NK3.3 function. The anti-HLA class I and class II antibodies could each be grouped into functional categories based on their ability to enhance, inhibit, or not affect the lysis of NK-sensitive targets K562 and MOLT-4 by NK clone 3.3. These results demonstrate, for the first time, a potential involvement of MHC molecules with NK function.

Animals↗

PubMed1992

Allorecognition of isolated, denatured chains of class I and class II major histocompatibility complex molecules. Evidence for an important role for indirect allorecognition in transplantation.

Classical RT1-A class I and RT1-B class II major histocompatibility complex (MHC) molecules were purified from DA (RT1avl) spleens, and the individual chains separated and purified by preparative polyacrylamide gel electrophoresis in sodium dodecyl sulfate. LEW (RT1l) rats were immunized with the pure class I heavy chain, the RT1-B alpha chain and the RT1-B beta chain with the aim of priming to indirect allorecognition (i.e. after processing and presentation of DA MHC chains on LEW antigen-presenting cells) in the absence of any priming to direct allorecognition (i.e. to whole, undenatured, dimeric DA MHC molecules). LEW rats immunized with each of the three DA MHC chains produced alloantibodies to these chains, suggesting that indirect allorecognition did occur, because of the requirement for cognate recognition of B cells by T helper cells. This also demonstrated polymorphism of all three chains between the DA and LEW strains. The antibodies to the isolated, denatured MHC chains did not react to the whole MHC molecules on DA cells, with the possible exception of very weak reactions in some class I heavy chain-immunized rats. DA skin grafts placed on LEW recipients immunized with each of the DA MHC chains were rejected in an accelerated fashion. Following DA skin grafting, there was an accelerated production of antibodies to whole, undenatured class I MHC molecules, even in the LEW rats preimmunized with RT1-B alpha and RT1-B beta chains. These data suggest that indirect allorecognition can play an important role in the effector mechanisms of allograft rejection, and demonstrate T helper priming as one possible mechanism whereby this might be effective.

Animals↗

PubMed1994

Decreased anti-donor major histocompatibility complex class I and increased class II alloantibody response in allograft tolerance in adult rats.

Permanent tolerance to allografts can be induced in adult rats by donor-specific transfusions (DST) prior to transplantation. We have previously reported, in a model of heart allograft, the presence of a heavy leukocyte infiltrate, in the allograft which displayed a strong allospecific cytotoxicity when tested in vitro against donor cells, and a strong accumulation of mRNA for granzyme A and perforin in vivo. In contrast, there was a major decrease in the accumulation of mRNA for interleukin-2 and interferon-gamma. These results suggested that the DST-induced tolerance was associated with a decrease in type-1 T helper (Th1) cell function. The major role of preformed antibodies in xeno and allorejection is clearly established. Nevertheless, the consequences of alloantibody production in acute rejection and tolerance induction remains to be elucidated. We here analyze the alloantibody response in rejecting and DST-treated recipients. We show that, after transplantation, tolerant recipients, in contrast to rejecting ones, mount a low IgM alloresponse that switches to low IgG production. Detailed analysis of IgG alloantibodies in DST-treated recipients revealed that their production decrease was not equally distributed. Whereas rejecting animals mounted a strong anti-class I and II IgG alloantibody response, DST-treated recipients produced anti-class II and low titers of anti-class I IgG alloantibodies. Furthermore, among IgG subclasses, tolerant recipients predominantly produced IgG2a, a profile which, in the rat, is compatible with a Th2-controlled response. Finally, the passive transfer of immune serum from rejecting animals to DST-treated recipients could abrogate the tolerance. We suggest that the absence of anti-class I alloantibodies combined with preserved and/or increased anti-class II production plays a major role in graft tolerance in this model. These results reinforced the role of alloantibodies in rejection and in induction of tolerance.

Animals↗

PubMed1990

Hepatic expression of class I and class II major histocompatibility complex molecules in primary biliary cirrhosis: effect of ursodeoxycholic acid.

Aberrant hepatic expression of HLA molecules has been shown to be present in primary biliary cirrhosis and may play a determining role in the pathogenesis of the disease. We have studied the effect of the long-term administration of ursodeoxycholic acid on hepatic HLA expression. Nine untreated patients with primary biliary cirrhosis, eight patients treated for at least a year with ursodeoxycholic acid and eight control subjects without hepatobiliary disease were compared. HLA expression was studied on liver biopsy sections using a direct immunofluorescence technique with specific monoclonal antibodies directed against class I or class II HLA molecules. Aberrant biliary HLA class II expression was not modified by chronic administration of ursodeoxycholic acid. In contrast, aberrant hepatocyte HLA class I expression was markedly reduced. Reduction in HLA class I expression may lead to decreased cytotoxic T cell-dependent lobular necrosis, which is thought to contribute to the progression of primary biliary cirrhosis to advanced stages. These findings suggest that the beneficial effect of ursodeoxycholic acid treatment in primary biliary cirrhosis could result not only from a reduction in the intrahepatic accumulation of cytotoxic bile acids but also from a reduction in immunological injury.

Deoxycholic Acid↗

PubMed1991

Class-I MHC expression in the mouse lung carcinoma, line 1: a model for class-I inducible tumors.

We have examined the expression and biological effects of class-I MHC molecules on the immune response to the line I lung carcinoma. The line I system is of interest because these tumor cells have very low constitutive levels of class-I molecules but can be induced to express levels found on spleen cells, by culturing the cells with agents such as dimethylsulfoxide (DMSO) or interferon gamma (IFN-gamma). This induction is significant immunologically, since induced cells can be lysed very effectively by cytotoxic T lymphocytes (CTL), whereas the uninduced cells cannot. CTL clones that are reactive with line I cells have been generated and used in vitro and in vivo, to examine the interactions of T cells with line I. We have shown that the expression of class I on tumor cells is induced in vivo by IFN-gamma, and that this induction is associated with the ability to reject the tumor. We will also introduce preliminary data concerning the mechanism of induction in which CTL appear to induce class-I MHC both in vitro and in vivo. The results are discussed in terms of a model which may be important generally for class-I inducible tumors.

Animals↗

PubMed1994

The cotton-top tamarin revisited: Mhc class I polymorphism of wild tamarins, and polymorphism and allelic diversity of the class II DQA1, DQB1, and DRB loci.

Cotton-top tamarins (Saguinus oedipus) in captivity are unusual in that they exhibit low levels of polymorphism and allelic diversity at the major histocompatibility complex (Mhc) class I loci. Since the polymorphism has previously only been examined in captive tamarins, we analyzed the Mhc class I alleles of a population of wild tamarins. These wild tamarins, like their captive counterparts, exhibited limited class I polymorphism. We also assessed the levels of polymorphism and allelic diversity at the Mhc class II DQA1, DQB1, DQB2, and the DRB loci in captive populations of cotton-top tamarins. In contrast to the extensive polymorphism in Old World monkeys, only two alleles were detected at each of DQA1 and DQB1. Also, the DQB2 locus was monomorphic and conserved between New and Old World monkeys. Sequences derived from four putative DRB loci were obtained, and extensive polymorphism was found at all four loci. Phylogenetic analysis did not indicate that any of the tamarin DRB loci, with the possible exception of Saoe-DRB3, were orthologous to the human DRB loci. At three of the DRB loci (Saoe-DRB11, Saoe-DRB*W12, Saoe-DRB*W22), the number of nonsynonymous changes was higher than the number of synonymous changes in the putative antigen recognition sites, indicative of positive selection. We found no support for a restriction on the polymorphism at the cotton-top tamarin class II loci. However, the allelic diversity at some of the Saoe-DRB loci is more limited than for the HLA-DRB1, consistent with a restriction imposed by the bone marrow-chimerical lifestyle.

Alleles↗

PubMed1992

Reptilian class I major histocompatibility complex genes reveal conserved elements in class I structure.

The polymerase chain reaction was used to isolate clones with class I major histocompatibility complex sequences from fish (carp), amphibian (axolotl), and two species of reptile (lizard and snake). The lizard and snake clones were used to isolate class I cDNA clones. All the sequences showed the expected evolutionary relatedness. The carp and axolotl clones and one lizard cDNA clone lacked the first cysteine in the alpha 3 domain which in other class I heavy chains forms an intradomain disulfide bond. A small number of amino acid residues are conserved in the class I heavy chain sequences from all five classes of vertebrates. In the first two domains they are symmetrically clustered and contribute to intra- and interdomain contacts. None of these invariant residues are at peptide-binding, T-cell receptor-interacting, or CD8-binding positions.

Amino Acid Sequence↗

PubMed1982

Postpharyngeal lymphoid tissue in Angle Class I and Class II malocclusions.

Opinions differ with regard to the relationship of adenoids and type of malocclusion. To study this possible relationship, xeroradiographic lateral cephalograms were made of eighty Class I (Angle) and sixty-four Class II, Division 1 (Angle) malocclusions to obtain reliable measures of the epipharyngeal lymphoid tissue, the nasopharyngeal airway, the nasopharynx, and certain cephalometric landmarks. Xeroradiographic cephalograms provide superior visualization with edge-enhancement effect for both soft and hard tissues. Electronic digitization and a comprehensive computer analysis were used to assess the head films. Significant differences were found for some of the linear and angular cephalometric criteria between the two malocclusion categories. A sexual dimorphism was observed. These skeletal and dental differences were anticipated in this mixed malocclusion sample, as prior cephalometric studies which compare different classes of malocclusion have shown. Airway space did not appear to vary with the type of malocclusion. Some low-level correlations were found between the size of the nasopharyngeal area and certain skeletal characteristics. These correlations depended on both the malocclusion type and the sex of the individual. The lateral, two-dimensional cephalogram does not seem to offer satisfactory information relating the nasopharyngeal area to Class I or to Class II, Division 1 malocclusions.

Cephalometry↗

PubMed1989

Phosphorylation of class I but not class II MHC molecules by membrane-localized protein kinase C.

Membranes were isolated from B cells stimulated with phorbol 12-myristate 13-acetate (PMA) for a time sufficient to allow maximal redistribution and activation of protein kinase C (PKC). Exposure of such membranes to a short incubation with [gamma-32P]ATP resulted in the detection of at least nine unique or hyperphosphorylated membrane proteins by SDS-PAGE and autoradiography. The appearance of these phosphoproteins was blocked by pretreatment of the membranes with H-7 or sangivamycin, two selective inhibitors of PKC. In addition, membranes purified from B cells treated with an inactive phorbol ester or stimulated with dibutyryl cAMP failed to exhibit a pattern of new phosphoproteins. These results are consistent with the involvement of PKC in the phosphorylation of the proteins. These phosphoproteins are also candidates for proteins whose functions are modified as a consequence of early signal delivery to resting B cells following membrane immunoglobulin occupancy. This system was utilized to identify the heavy chain of MHC class I molecules as one of the membrane proteins phosphorylated by PKC. The MHC class II molecules were not phosphorylated in membranes isolated from PMA-treated normal B cells or from PMA-treated B cells which had previously been exposed to IL-4. These results indicate that class I, but not class II, MHC molecules are phosphorylated by PKC. It is possible that such a modification of cell surface class I molecules may be involved during the process of signal transduction leading to B cell activation.

Animals↗

PubMed2005

Differential modulatory effect of NGF on MHC class I and class II expression in spinal cord cells of EAE rats.

Nerve growth factor (NGF) undergoes significant changes in the central nervous system (CNS) of patients affected by multiple sclerosis (MS) and of rats with experimental allergic encephalomyelitis (EAE). The major histocompatibility complex (MCH) class I and class II antigens are molecules that play a pivotal role in these neuro-inflammatory disorders. The aim of this study was to investigate the role of NGF on MCH class I and class II antigens in spinal cords cells of EAE rats. It was found that the administration of NGF in EAE rats enhances MHC-I, IFN-gamma receptor and interferon regulatory factor-1 expression on the neurons but not in the glial cells, while NGF decreased MHC class II antigen in the glial cells. NGF administration into the brain of EAE rats has no effect on TNF-alpha expression. The present findings suggest that NGF may have a regulatory function in spinal cord cells during tissue inflammation.

Analysis of Variance↗

PubMed2000

Class I and class II anti-HLA antibodies after implantation of cryopreserved allograft material in pediatric patients.

OBJECTIVES: Very little is known regarding the immune response to cryopreserved allograft valves and patch material used in the surgical repair of congenital heart defects. METHODS: We prospectively measured the frequency of panel reactive antibodies directed against HLA class I (HLA-A, B, and C) and class II (HLA-DR/DQ) alloantigens in 24 children receiving cryopreserved allografts. We compared them with results in 11 previously reported control patients. Sixteen of the study patients underwent placement of a valved conduit (11 pulmonic, 5 aortic) between the right ventricle and pulmonary arteries, 6 underwent patch angioplasty of stenotic vessels with cryopreserved pulmonary artery, and 2 underwent placement of a pulmonary monocusp patch. Study patients had panel reactive antibodies measured before, 1 month, 3 months, and 1 year after the operation. RESULTS: With allograft implantation, panel reactive antibodies increased from 1.9% +/- 5% before the operation to 62% +/- 33% at 31 +/- 8 days after the operation, 92% +/- 15% at 3.3 +/- 0.6 months after the operation, and 85% +/- 18% at 1.1 +/- 0.2 years after the operation. The control group showed no change in panel reactive antibodies, with a level of 1.6% +/- 1% before the operation, 3.2% +/- 1% 28 +/- 5 days after the operation, and 1.7% +/- 1% 2.7 +/- 0.3 months after the operation. Class II antibodies (anti-HLA-DR/DQ) rose to 49% +/- 35% at 30 +/- 8 days and 70% +/- 26% at 3.3 +/- 0.6 months after the operation. CONCLUSIONS: Cryopreserved allograft material induces a marked response that involves both class I and class II anti-HLA antibodies within 3 months after operation in children. This alloantibody response may represent a form of "rejection," may have implications for those who require subsequent cardiac transplantation, and may play a role in early allograft failure.

Adolescent↗