Identification and characterization of mitochondria autoantigens in progressive systemic sclerosis: identity with the 72,000 dalton autoantigen in primary biliary cirrhosis

Sera from eight out of 62 (14.5%) patients with progressive systemic sclerosis (PSS) reacted by immunoblotting with a 72,000 dalton antigen and one, a patient with concomitant primary biliary cirrhosis (PBC), reacted with the 72,000 dalton and a 47,000 dalton antigen. Reactivity with these antigens was not seen with any of 111 control sera. The antigens with minor variations in m.w. were present in a variety of cultured cells and tissue homogenates from different species. Subcellular fractionation studies localized the antigens to the mitochondria. Of 19 sera from patients with other diseases selected for immunofluorescence staining for anti-mitochondria autoantibody, nine reacted with the 72,000 dalton antigen, seven reacted with both the 72,000 and 47,000 dalton antigens, and three reacted with the 47,000 dalton antigen. These results show that serum reactivity with the 72,000 dalton and 47,000 dalton mitochondria autoantigens is found with some patients with PSS. Because mitochondria autoantibodies that are reactive with the 72,000 dalton and 47,000 dalton polypeptides are also found in patients with PBC, the present finding provides additional support for the association of PSS with PBC. Prior absorption of rat liver homogenate with PBC sera removed PSS serum reactivity with a 63,000 dalton antigen, the equivalent 72,000 dalton antigen in rodents, and vice versa, showing that both PBC and PSS sera recognize the same antigen.     

Use of Stable, Sensitized Cells in Indirect Micro Hemagglutination Test for Amebiasis

Human "O" cells were fixed with pyruvic aldehyde, treated with tannic acid, and fixed with glutaraldehyde. The cells were sensitized with amoeba antigen and stored in a refrigerator. The sensitized cells were used periodically for the indirect hemagglutination test with a battery of sera from patients with intestinal amebiasis and confirmed and unconfirmed amebic liver abscess, and also from negative controls. The same battery was tested with cells sensitized with different batches of antigen and also with fresh sheep cells. None of the cells showed any reaction with negative control sera. The fixed cells remained sensitive and stable throughout the study. Reproducibility of the titers with the fixed cells within each day and from day to day was satisfactory. The titers with fixed human "O" cells were slightly lower than were the titers with fresh sheep cells. The advantages of using stable, sensitized cells are pointed out.     

Unresponsiveness of rat peritoneal mast cells to immunologic reactivation.

Rat peritoneal mast cells cocultured with 3T3 fibroblasts (MC/3T3) were activated with Ag or with anti-IgE antibodies in the presence of Ca2+, and their responsiveness to a second similar challenge was evaluated. MC/3T3 were presensitized with IgE anti-DNP antibodies and activated with DNP-human serum albumin. When these MC/3T3 were reactivated with the same Ag 2 and 6 h later, they released only a minimal percentage of histamine. A gradual recovery of responsiveness was detected during the first 7 days after activation, and a full recovery was attained by days 14 to 21. A similar pattern of unresponsiveness was observed when MC/3T3 were challenged and rechallenged with cercarial Ag after presensitization with anticercarial serum. Activation of MC/3T3 with one Ag (DNP-human serum albumin or cercarial) and rechallenge 3 days later with the other Ag did not overcome the state of partial unresponsiveness. Challenging MC/3T3 with anti-IgE led to a subsequent unresponsiveness to rechallenge with the same ligand, regardless of whether or not the cells were presensitized with IgE antibodies. Cross-linkage with anti-IgE resulted in a more intense and prolonged state of unresponsiveness in comparison with that observed with Ag. When MC/3T3 activated with anti-IgE were rechallenged with various IgE-independent agents they released a percentage of histamine comparable to that of control cultures challenged with these secretagogues for the first time. MC/3T3 partially resynthesized their histamine content during the two-week period after activation. Our results suggest that MC undergo a temporary state of "physiologic" unresponsiveness after immunologic activation in the presence of calcium ions.     

长刺萤叶甲属与短鞘萤叶甲属的外部形态扫描电镜观察

本文对长刺萤叶甲属和短鞘萤叶甲属的头部,口器,触角,体毛,刻点,前胸背板,鞘翅缘折,足的外部形态首次进行了扫描电镜观察,并对结果进行了分析,比较,发现纬度变化引起的形态变异不显著,而海拔的变化引起形态的适应性变化比较显著。因此,对两种不同海拔的萤叶甲进行形态比较,研究萤叶甲在不同地理环境下,其形态的适应性变化提供了有价值的依据。     

妊娠合并甲状腺功能亢进症23 例临床分析

目的:探讨妊娠合并甲状腺功能亢进症的孕妇的妊娠结局,对母体造成的影响,抗甲状腺药物的使用情况及分娩方式。方法:对23例甲状腺功能亢进孕妇进行了回顾性分析,观察该病对孕妇的影响,对母儿造成的不良结局。结果:23例甲状腺功能亢进孕妇合并轻度妊娠高血压综合征的2例,中度4例,重度2例。合并心衰6例,合并胎膜早破5例,胎盘粘连2例,甲状腺危象1例,胎盘早剥1例,产后出血1例,前置胎盘1例。23例甲状腺功能亢进顺产6例,产钳1例,胎头吸引1例,剖宫产15例。出现早产9例,其中5例为医源性早产。胎儿宫内窘迫6例,死胎1例。结论:妊娠合并甲状腺功能亢进症常危及母婴健康,为降低母儿风险,孕前需很好地控制病情,孕期密切监控,合理治疗。     

Immunohistochemical heterogeneity of alpha-tubulin in human epithelia revealed with monoclonal antibodies

Summary Four monoclonal antibodies raised to alpha subunit of pig brain tubulin (TU-01, TU-02, TU-03, TU-04) were used to study immunohistochemical heterogeneity of alpha tubulin in human epithelia. Selective reactivity was detected in the skin and trachea/bronchi, whereas all other epithelia investigated reacted uniformly with all four monoclonal antibodies. In the skin TU-01 reacted very strongly with all layers except the basal layer; TU-02 reacted strongly with granular layer and was unreactive or only weakly reactive with others; TU-03 reacted very strongly with basal layer and weakly to moderately with superficial layers; TU-04 reacted strongly with the granular layer of epidermis and was unreactive with other layers. In the trachea and major bronchi TU-01 reacted with the entire epithelial layer; TU-02 reacted only with superficial layer; TU-03 reacted with superficial and basal layer; TU-04 reacted only with superficial layer. Different staining patterns obtained with these four monoclonal antibodies indicate that there is immunohistochemical heterogeneity of alpha tubulin in some but not all normal human epithelia.     

棉铃虫性诱剂在测报和防治上的应用研究

1993～1996年对棉铃虫性诱剂在测报和防治上的应用效果进行调查研究,结果表明,在3种不棉铃虫性诱剂中以中国科学院动物研究所生产的性诱剂诱蛾效果最好,其效果与进口性诱剂相当。在第1代,性诱剂诱蛾效果好于杨树把。在第2代,其效果与杨树把接近。在第3、4代,其效果差于杨树把。性诱剂与杨树把诱蛾的蛾量消长基本同步并且两者与田间卵量消长基本一致。因此,在第1、2代应以性诱剂取代杨树把,在第3、4代应以杨树把进行测报和防治。     

New data on aberrant spermatozoa in the ejaculate of Sus domesticus

This paper describes 16 new types of aberrant spermatozoa observed by scanning electron microscopy in the ejaculate of two healthy, sexually mature Landrace boars. The new anomalies observed were 1) spermatozoa with folded tail and abnormal head; 2) tailless spermatozoa with an abnormal connecting piece; 3) immature spermatozoa with two tails of the same length, fused and coiled; 4) spermatozoa with two tails of the same length, fused and coiled, and a small, rounded head; 5) spermatozoa with two fused tails and a wide head; 6) spermatozoa with three tails of the same length, fused and coiled; 7) immature spermatozoa with two heads and two fused tails; 8) spermatozoa with two heads, one at each tip of the tail; 9) spermatozoa with a short, folded tail and a triangular head; 10) spermatozoa with a short tail lacking the intermediate piece; 11) spermatozoa with a short tail, without the main piece and with a long intermediate piece; 12) spermatozoa with a short tail, without the main piece and with a rough head; 13) spermatozoa with small, rounded head; 14) spermatozoa with small, aberrant heads; 15) spermatozoa with small, bacillary heads; and 16) immature spermatozoa with tapering heads.     

陆军青年军人心理素质与人格、心理健康的相关研究

目的:探讨陆军青年军人心理素质与人格、心理健康的关系。方法:整群抽取陆军青年官兵881名,采用军人心理素质量表、艾森克人格问卷(EPQ)、症状自评量表(SCL-90)进行测评,进行方差分析和相关分析。结果:(1)陆军青年军人心理素质各因子分及总分与EPQ人格问卷中的E分呈显著正相关(p<0.01);与N分、P分呈显著负相关(p<0.01)。高、中、低心理素质水平军人E、P、N得分比较有显著差异(p<0.05),表现为在E量表得分上高心理素质组>中等心理素质组>低心理素质组;而在P、N量表得分上则反之。(2)陆军青年军人心理素质各因子分及总分均与SCL-90各因子分和总均分呈显著负相关(p<0.01)。高、中、低心理素质水平军人SCL-90各因子得分比较有显著差异(p<0.05),表现为低心理素质组>中等心理素质组>高心理素质组。结论:陆军青年军人心理素质与心理健康密切相关,心理素质越高,其心理健康水平也越高。     

剪形臂尾轮虫形态的时空变化及其与生态因子间的关系

对芜湖市镜湖和汀棠湖中剪形臂尾轮虫(Brachionus forficula)的发生及其形态特征进行了一年的观察,并分析了其与环境因子间的关系。结果表明,镜湖中,剪形臂尾轮虫出现于7月至10月,且仅存在短后棘刺型个体;2样点内,除了前外棘刺长以外,轮虫的其他各形态参数均随季节显著变化,形态参数的样点间差异也因季节的不同而异;轮虫的各形态参数均随pH的升高而延长,随过滤水体中叶绿素a含量和水体中总叶绿素a含量的升高而缩短;体长和体宽均随晶囊轮虫密度的升高而增大。汀棠湖中,短后棘刺型个体出现于6月至10月,而长后棘刺型个体仅出现于6月至8月;2种形态型个体同时存在时,长后棘刺型个体在种群中所占比例始终高于短后棘刺型个体,并与水温、水体中总叶绿素a含量以及枝角类、桡足类和晶囊轮虫的密度均呈显著的正相关;2样点轮虫短后棘刺型个体各形态参数均随季节显著变化;长后棘刺型个体在1号样点内仅前外棘刺和后棘刺长有显著变化,而2号样点内仅体长、体宽和后棘刺长有显著变化;2样点内长后棘刺型个体的体长、体宽以及前外棘刺和后棘刺均显著长于短后棘刺型个体;同一形态型个体形态参数的样点间差异因季节的不同而异;短后棘刺型个体的前外棘刺和后棘刺长均与水体中总叶绿素a含量呈显著的正相关,后者与过滤水体中叶绿素a含量和枝角类密度也呈显著的正相关;长后棘刺型个体的后棘刺长与桡足类密度呈显著正相关,前内棘刺长与水温、溶氧量和晶囊轮虫密度呈显著负相关。两湖泊内剪形臂尾轮虫的后棘刺长和体长之间均呈显著的正相关,提示其后棘刺的延长并不是对体长的异速增长。     

陆军青年军人心理素质与人格、心理健康的相关研究

目的：探讨陆军青年军人心理素质与人格、心理健康的关系。方法：整群抽取陆军青年官兵881名,采用军人心理素质量袁、艾森克人格问卷（EPQ）、症状自评量表（SCL-90）进行测评,进行方差分析和相关分析。结果：（1）陆军青年军人心理素质各因子分及总分与EPQ人格问卷中的E分呈显著正相关（p〈0．01）;与N分、P分呈显著负相关（p〈0．01）。高、中、低心理素质水平军人E、P、N得分比较有显著差异（p〈0．05）,表现为在E量表得分上高心理素质组〉中等心理素质组〉低心理素质组;而在P、N量表得分上则反之。（2）陆军青年军人心理素质各因子分及总分均与SCL-90各因子分和总均分呈显著负相关（p〈0．01）。高、中、低心理素质水平军人SCL-90各因子得分比较有显著差异（p〈0．05）,表现为低心理素质组〉中等心理素质组〉高心理素质组。结论：陆军青年军人心理素质与心理健康密切相关,心理素质越高,其心理健康水平也越高。     

The effect of different krill meals fed to laboratory rats on their blood indices.

1. In 102 laboratory rats fed with (a) the krill standardized meal, (b) the krill meal with low chitin content, (c) the casein diet with D,L-methionine, (d) the casein diet with D,L-methionine supplemented with the krill carapace meal, (e) the casein diet with D,L-methionine supplemented with ash from the krill standardized meal and (f) the control diet--"Murigran" standard pelleted feed; the different blood indices were investigated. 2. The mean values of following indices: the number of erythrocytes and leucocytes, the percentage of leucocytes, the corpuscular haemoglobin concentration and red blood cell diameter were similar in all experimental and control groups. 3. The mean values of haematocrit and haemoglobin levels, the mean corpuscular thickness and volume were lower in rats fed with the casein diet with D,L-methionine supplemented with the krill carapace meal than in other groups. 4. All kinds of investigated indices were similar in rats fed with krill meal with low chitin contents, whose parents received the standardized krill meal and no sex differences have been shown here.     

Echocardiographic Findings in Patients With Normocalcemic Primary Hyperparathyroidism Compared With Findings in Hypercalcemic Primary Hyperparathyroid Patients and Control Subjects

ObjectiveThere are no data regarding echocardiographic parameters in patients with normocalcemic primary hyperparathyroidism (NCPHPT). We compared the echocardiographic findings in postmenopausal women with NCPHPT with those in patients with hypercalcemic primary hyperparathyroidism (PHPT) and controls.MethodsSeventeen consecutive Caucasian postmenopausal women with NCPHPT were compared with 20 women with hypercalcemic PHPT and 20 controls. Obesity, diabetes, kidney failure, and previous cardiovascular diseases were considered exclusion criteria. Each patient underwent biochemical evaluation, bone mineral density scan, and echocardiographic measurements. Patients with parathyroid disorders underwent kidney ultrasound evaluation.ResultsPatients with PHPT had significantly higher mean total serum calcium, ionized calcium, 24-hour urinary calcium, and parathyroid hormone and lower mean phosphorus levels compared with those in the controls (all P < .05). The only differences between patients with NCPHPT and PHPT were significantly lower mean total serum calcium, ionized calcium, and 24-hour urinary calcium and higher phosphorus levels in patients with NCPHPT (all P < .05). The only biochemical difference between patients with NCPHPT and the controls was a higher level of mean parathyroid hormone in patients with NCPHPT. There were no differences in cardiovascular risk factors between patients with NCPHPT and PHPT and the controls. Hypertension was the most frequent cardiovascular risk factor, diagnosed in 65% of patients with PHPT. This high prevalence was not statistically significant compared with that observed in patients with NCPHPT (59%) and in the controls (30%). Echocardiography parameters were not different between patients with NCPHPT and PHPT and the controls when subdivided according to the presence of hypertension (ANOVA followed by Bonferroni correction).ConclusionIn a population with a low cardiovascular risk, we found no differences in cardiovascular risk factors and echocardiographic parameters between patients with NCPHPT and PHPT and the controls.     

THE TOPICAL AND SYSTEMIC USE OF CORTISONE IN DERMATOLOGY

Part I of this report deals with the topical use of cortisone in a variety of skin diseases. Fifteen patients with chronic discoid lupus erythematosus, four patients with necrobiosis lipoidica diabeticorum, four with psoriasis, one with lichen planus and one with granuloma annulare were treated with cortisone ointment. All the patients with chronic discoid lupus erythematosus had some degree of improvement. In two patients with chronic lupus erythematosus, complete clearing of the eruption occurred. In four patients with necrobiosis lipoidica diabeticorum remarkable involution resulted. Patients with psoriasis, lichen planus and granuloma annulare were not benefited.Part II deals with the systemic use of cortisone. Eight patients with severe serum sickness-like penicillin reaction responded dramatically to parenterally administered cortisone. In two cases of pemphigus vulgaris and one case of Sulzberger-Garbe disease, the disease was kept in remission with cortisone administered intramuscularly as well as orally. Partial improvement resulted in a case of localized myxedema associated with malignant exophthalmus. Two patients with exfoliative dermatitis due to therapy with heavy metals responded dramatically to cortisone. No beneficial effects were noted in patients with chronic urticaria and atopic dermatitis.The systemic use of ACTH and cortisone in dermatology at present should be confined to patients with known fatal or hopelessly incapacitating diseases and to patients with extreme hypersensitivity reactions which may be protracted or life-endangering, and which can be controlled or cured with a relatively small total dosage of the agents in a short time.     

Value of determining the spectrum of blood serum fatty acids in evaluating increasing the effectiveness of antibiotic therapy of dysentery in children with prodigiozan and ephedrine

One hundred and ninety one children with acute Sonne and Flexner dysentery were observed with respect to the disease process, immunity indices and blood serum fatty acid spectrum. 104 children were treated with monomycin alone and 87 children were treated with the antibiotic in combination with prodigiozan and ephedrine as immunostimulators. It was shown that the recovery terms in the patients treated with the use of the immunostimulators decreased as compared to the patients treated with the antibiotic alone. The fatty acid spectrum in the children treated with the use of the immunostimulators differed from that in the children treated without them by low levels of fatty acids of the C12:0 to C18:1 composition.     

Immunochemical characterization of the anti-RNA antibodies found in scleroderma and systemic lupus erythematosus. I. Differences in reactivity with Poly (U) and Poly-(A) Poly (U).

In a previous study, all 40 sera from patients with scleroderma, 20 of 40 sera from SLE patients, but none of 40 sera from normal controls, were found to have antibodies to ssRNA. All scleroderma sera were also found to react with HSA-coupled uridine and UMP and their reaction with HSA-coupled uridine and UMP and their reaction with ssRNA could be inhibited by uracil, uridine, and UMP. To characterize further these uracil-specific anti-RNA antibodies found in scleroderma and compare them with the anti-RNA antibodies found in SLE, we tested their reactivity with Poly (U) and with Poly (A)-Poly (U) and all but one failed to react with Poly (A)-Poly (U). This same serum was the only one in which the reaction with Poly (U) could not be inhibited with uracil. Reactivity of SLE sera was strikingly different from that found in scleroderma sera. Seventeen of 34 SLE sera studied reacted with ssRNA but only four of these reacted with Poly (U). Conversely, two SLE sera that reacted with Poly (U) did not react with ssRNA. Fifteen reacted with Poly (A)-Poly (U) and only two of these failed to react with ssRNA. Five SLE sera which were reactive with ssRNA did not precipitate with Poly (A)-Poly (U). All SLE sera which reacted with Poly (U) could be inhibited with uracil, although less effectively than in scleroderma. Reactivity with Poly (A)-Poly )U) was not inhibited with uracil nor with adenosine. These findings confirm that antibodies to RNA that are found in scleroderma are directed to uracil and thus specific to ssRNA, whereas RNA antibodies found in SLE sera are heterogeneous and directed to either the base, to the site of union of the base and sugar moiety to the ribose backbone, or to the helical structure of double stranded RNA. These differences and the respective antigenic specificities of these anti-RNA antibodies found in scleroderma and SLE may be theoretically important.     

Functional evaluation of the adenohypophysis with metoclopramide in hyperprolactinemic-amenorrheic women in relation to radiological findings on the sella turcica

The responses of the adenohypophyseal hormones to metoclopramide (MCP) were evaluated in hyperprolactinemic women with various radiological findings on the sella turcica. Serum PRL concentrations significantly increased after MCP administration in normal women, hyperprolactinemic patients with normal sella and patients with microadenoma, but not in macroadenoma patients with and without suprasellar expansion (SSE). The PRL response to MCP administration was significantly lower in hyperprolactinemic patients than in normal women. Serum TSH concentrations significantly increased after MCP administration in each group of subjects. The TSH response to MCP was significantly higher in patients with normal sella and patients with microadenoma than in normal women. However, the responses of PRL and TSH to MCP were not significantly different between patients with normal sella and patients with microadenoma. Therefore, they were not considered useful in distinguishing tumorous from nontumorous hyperprolactinemia. Serum LH concentrations significantly increased after MCP administration in patients with normal sella, patients with microadenoma and macroadenoma patients without SSE, but not in normal women or macroadenoma patients with SSE. The LH response to MCP was significantly higher in patients with microadenoma than in patients with normal sella. Serum FSH concentrations significantly increased after MCP administration only in patients with microadenoma. The different responses of the adenohypophyseal hormones to MCP in hyperprolactinemic women with various radiological findings on the sella turcica may be explained by the difference in the hypothalamic dopamine activity and in the impairment of the hypothalamic-pituitary system due to pituitary tumor.     

Immunochemical analysis of cartilage proteoglycans. Antigenic determinants of substructures.

Antibodies were raised in rabbits by injection of cartilage proteoglycan monomers, isolated hyaluronic acid-binding region, polysaccharide-peptides prepared by trypsin digestion of proteoglycans and link-protein. The rabbits injected with the proteoglycan monomers made antibodies reacting with the intact proteoglycan. The antiserum contained antibodies specific for, and also reacting with, the isolated hyaluronic acid-binding region and the keratan sulphate-rich region. In addition there were probably antibodies reacting with other structures of the proteoglycan monomer. When isolated hyaluronic acid-binding region was used for immunization the antibodies obtained reacted specifically with the hyaluronic acid-binding region. The antibodies obtained from rabbits immunized with the polysaccharide-peptides reacted with the proteoglycan monomers and showed a reaction identical with that of the chondroitin sulphate-peptides isolated after trypsin digestion of proteoglycans. The antibodies prepared with the link-protein as the antigen reacted only with the link-protein and not with any preparation from the proteoglycan monomer. Neither did any of the antisera raised against the proteoglycan monomer or its substructures react with the link-protein. Separately it was shown that the peptide 'maps' prepared from trypsin digests of the link-protein and the hyaluronic acid-binding region were different. Therefore it appears that the link-protein is not structurally related to the proteoglycan or the hyaluronic acid-binding region. Digestion of proteoglycan monomers or isolated hyaluronic acid-binding region with trypsin did not destroy the antigenic sites of the hyaluronic acid-binding region. In contrast trypsin digests of previously reduced and alkylated preparations did not react with the anti-(hyaluronic acid-binding region). The trypsin digests, however, reacted with both the antibodies directed against the chondroitin sulphate-peptides and those against the keratan sulphate-peptides. Trypsin digestion of the link-proteins destroyed the antigenic site and the reactivity with the antibodies. By combining immunoassay of proteoglycan preparations before and after trypsin digestion it is feasible to quantitatively determine its substructures by using the antisera described above.     

Associations between restriction fragment length polymorphisms detected with a probe for human 21-hydroxylase (21-OH) and two clinical forms of 21-OH deficiency

Summary DNAs from unrelated healthy individuals and unrelated individuals affected with 21-hydroxylase deficiency (congenital and late-onset adrenal hyperplasia) were digested with seven restriction enzymes and hybridized with a cDNA probe specific for human 21-hydroxylase genes. Associations were found between restriction fragments and the two forms of the disease: (i) The late onset form is associated with a double dose of a 14 kb fragment generated by Eco RI and with a triple dose of a 3.2 kb fragment generated by TaqI in patients with HLA B14 haplotypes; (ii) The classical congenital form is negatively associated with the 14 kb fragment and with a 3.7 kb fragment generated by TaqI in patients with HLA Bw47 haplotypes. A 3.2 kb TaqI fragment is negatively associated with the HLA B8 haplotypes. The other five enzymes tested give no polymorphisms or polymorphisms without correlation with the two forms of the disease.     

A study of anti-group A streptococcal monoclonal antibodies cross-reactive with myosin

Anti-group A streptococcal monoclonal antibodies were obtained from BALB c/BYJ mice immunized with purified membranes from M type 5 Streptococcus pyogenes. Two of the anti-streptococcal monoclonal antibodies were previously shown to cross-react with muscle myosin. In this study the monoclonal antibodies were reacted with tissue sections of normal human heart and skeletal muscle. Antibody binding was estimated by indirect immunofluorescence and immunoperoxidase techniques. Both of the monoclonal antibodies (36.2.2 and 54.2.8) investigated in this report reacted with heart and/or skeletal muscle sections. When evaluated by immunofluorescence, monoclonal antibody 54.2.8 demarcated the periphery of cardiac striated muscle cells and reacted to a lesser degree with subsarcolemmal components. Monoclonal antibody 36.2.2 failed to react with heart sections, but both of the monoclonal antibodies reacted strongly with skeletal muscle sections. Results similar to those observed with indirect immunofluorescence were obtained with the immunoperoxidase technique. By Western immunoblotting and competitive inhibition assays, monoclonal antibodies 36.2.2 and 54.2.8 both were found to react with the heavy chain of skeletal muscle myosin. However, only 54.2.8 reacted with the heavy chain of cardiac myosin. The specificity of the monoclonal antibodies for subfragments of skeletal muscle myosin indicated that monoclonal antibody 36.2.2 was specific for light meromyosin fragments, whereas 54.2.8 reacted with both heavy and light meromyosin. The data demonstrated that two monoclonal antibodies against streptococci were specific for skeletal muscle and/or cardiac myosin and for subfragments of the myosin molecule. The reactions of the monoclonal antibodies with human tissue sections were consistent with the immunochemical reactions of the monoclonal antibodies with both denatured and native myosin.