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Biomedical subjects

S Hsia

Publications and source records attributed to S Hsia.

At least 37 records · Page 2Linked to original sources
PubMed1982

Myotonic dystrophy: HLA antigens and mitogen stimulated lymphocyte responses of a black American family.

A Black American family of four generations with 29 members was studied. Six family members spanning two generations were affected with myotonic dystrophy. HLA A, B, C and DR antigen specificities were determined for each family member using local typing trays. Twelve HLA haplotypes were identified in the family. No significant association was found between the disease and any HLA antigenic type or haplotype. This finding suggests that the involvement of the major histocompatibility complex in the etiology of myotonic dystrophy is unlikely. The cellular responses to twenty-eight family members and 20 unrelated Black Americans to phytohemagglutinin (PHA), Concanavalin A (Con A) and pokeweed mitogen (PWM), each in three concentrations, were tested with mononuclear cells prepared from peripheral blood. There was a significant difference in responses of the affected family members as compared to the unaffected family members and the unrelated Black Americans. The PHA and PWM responses of the unaffected family members are not significantly different from those of the unrelated Black American controls; however, the Con A responses of the unaffected family members are significantly higher than those of the control group at the lowest Con A dosage. The possible systemic defects of cytoskeletal structures of the affected family members are discussed.

Black People↗
PubMed1981

The effects of electrophoretically "slow" and "fast" alpha-2 macroglobulin on mixed lymphocyte cultures.

It has been determined that alpha-2 macroglobulin (alpha 2M) is more suppressive of a mixed lymphocyte response (MLR) when complexed with proteinase than in its "native" state. Other alpha 2M preparations showed a moderate level of MLR suppression, but it is unlikely that this is a result of interaction with cellular proteinases. A panel of other proteinase inhibitors (alpha 1 PI, SBTI, BPTI, TLCK) did not suppress the MLR to the same extent as alpha 2M either when bound with or free from trypsin. A dose-responsive pattern of MLR suppression similar to that observed with purified proteinase-complexed alpha 2M was seen with serum containing proteinase-complexed alpha 2M. The population of cells that apparently conveys the suppressive property is the adherent cells (putative monocytes), which can reduce the MLR almost as well as unfractionated cells when exposed to alpha 2M. Most of these properties of alpha 2M were demonstrable in "serumless" medium with qualitative similarity to the MLR obtained in cultures performed with conventional serum supplemented medium. It was found that alpha 2M-trypsin complexes must be presented at or near culture initiation and remain in contact with the cells for a minimum of approximately 4 hr to have its optimum effect.

Blood↗
PubMed1979

Mixed lymphocyte reactions in serum-free medium.

Tissue culture medium supplemented with bovine serum albumin (BSA), rather than human serum, was found capable of supporting the proliferative response of cryopreserved human lymphocytes to allogeneic cells in a one-way mixed lymphocyte culture. Although total tritiated thymidine uptake was lower in BSA supplemented cultures than in serum supplemented cultures, stimulation indices were equivalent. Using 0.5% (w/v) BSA, peak tritiated thymidine uptake was observed on day 5 using 2 X 10(5) responders and 4X 10(5) stimulators per microtitre well. Calf skin gelatin was also found capable of substituting for serum, but gave lower levels of proliferation. Use of BSA offers distinct advantages for investigating the proliferative responses of human lymphocytes in serum-free media.

B-Lymphocytes↗
PubMed1977

Studies of viral antibody responses among Amish families.

Serum antibodies to adenovirus (ADN), cytomegalovirus (CMV), herpes simplex virus (HSV), influenza (INF), para-influenza (PAR), mumps (MUM), coxsackie B4 (Cox B4) and B5 (Cox B5) viruses were measured from 584 individuals belonging to 21 Indiana Amish families. Sex and age effects on antibody responses to cytomegalovirus were observed. Age effect on CMV, HSV, INF, PAR, MUM responses were also found. The percentage of responders to some of the viruses was shown to be age dependent, but the levels of antibody response were not affected by the difference in age. A familial basis for the antibody response was demonstrated. Attempts at demonstrating association between HLA haplotypes and responses were not successful. The unlikelihood of predominantly HLA-associated control of viral antibody response was discussed.

Adenoviruses, Human↗
PubMed1976

A simple method for screening human T and B lymphocyte alloantibodies.

An sRBC-hemolysin monolayer was employed for separating human lymphocytes into two sub-populations, adherent cells (predominantly B cells) and non-adherent cells (predominantly T cells). The separated cells were then tested simultaneously against predispensed sera by complement-mediated cytolysis for the presence of alloantibodies to either T or B cells. A total of 372 sera were screened. Antibodies specific for B cell antigens were found in 19 sera and 9 sera were found to contain antibodies to T-specific antigens.

B-Lymphocytes↗
PubMed1975

HL-A antigens in a Chinese population.

The HL-A antigens of a Chinese population now living on the island of Taiwan have been investigated with reagents obtained from and characterized in Caucasian populations and with antisera obtained from Chinese multiparous women. Both HL-A2, the most frequent specificity found, and HL-A9 appear highly heterogeneous in this Chinese population since groups of antisera used to define HL-A2 or 9 in Caucasians gave discordant reactions. Moreover, new associations were found using chi-square and cluster analyses, further demonstrating the complexity of HL-A in this Taiwanese population. Fourteen % of 1183 Chinese multipara sera and 237 sera from multiple tranfused individuals were lymphocytotoxic and could be placed by cluster analysis into three major groups.

Cytotoxicity Tests, Immunologic↗