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J Kalil

Publications and source records attributed to J Kalil.

At least 91 records · Page 5Linked to original sources
PubMed1990

Immunological tolerance in human transplantation. The possible existence of a maternal effect.

We analyzed data from 93 patients who received a kidney graft from their parents; 55 were transplanted with a kidney from their mothers (Mat.) and thirty-eight from their fathers (Pat.) The Pat. group has shown a better graft and patient survival as well as long-term renal function when compared with the Mat. group. This pattern was more evident with time. Long-term graft function assessed by creatinine levels also showed differences between the groups, favoring the Pat. group. The results are interesting since recent reports have claimed a tolerance developed by the individual to noninherited HLA antigens of their mother.

Adolescent↗
PubMed1989

DNA analysis of histocompatibility antigens: fragments from the recently identified DR loci.

1. The DR locus of class II histocompatibility antigens (HLA-DR) is routinely typed by microlymphocytotoxicity tests. However, the preparation of good antisera is a complex process which relies heavily on a well-defined cell panel. 2. We have studied homozygous typing-cells representing the most common DR specificities in order to determine their typing pattern at the DNA level. 3. Restriction fragment length polymorphism obtained using six restriction enzymes permitted us to identify most of the DR specificities, including recently described splits of the DRw6. Specific fragments were tentatively allocated to the three DRw52 alleles. 4. The number of beta genes present on DRw52 and DRw53 antigen carrying cells is also discussed.

Blotting, Southern↗
PubMed1989

DNA analysis of histocompatibility antigens: identification of new DQw specificities and of DPw patterns.

1. The HLA-D region of the major histocompatibility complex has several subregions, the most important of which are DR, DQ and DP. The genes coding for the beta chains of these proteins present most of the polymorphisms which result in the large variety of class II antigens observed. 2. We have studied the restriction fragment length polymorphism (RFLP) of the DQ beta and DP beta genes in order to establish accurate typing patterns. 3. The data show that DQ typing based on RFLP permits the identification of the recently described DQw1 splits (new antigenic specificities), DQw5 and DQw6. The TA10-monoclonal antibody-positive split of DQw3, designated DQw7, is associated with specific DNA fragments after digestion with four different enzymes: Taq I, Hind III, Pvu II and Bgl II. Furthermore, the recently reported specificity DQw4 (formerly typed as a blank) is associated with a specific 2.4-kb fragment when the DNA is digested with EcoRV. 4. DP typing proved to be more difficult even though six enzymes were used, and only broad groups could be identified.

Blotting, Southern↗
PubMed1989

DNA analysis of histocompatibility antigens of a sample of the São Paulo population.

1. Human major histocompatibility complex (HLA) antigens have attracted great interest because of their prominent role in cell-mediated immune response and thus in graft rejection. An enormous variety of histocompatibility antigens has been demonstrated and the number of known antigens increases every year. 2. The objective of the present study was to apply restriction fragment length polymorphism (RFLP) analysis to the normal population of São Paulo in order to confirm and extend the scope of our laboratory's cell panel for HLA typing. 3. DNA typing of class I antigens has not been very productive since only some specificities correlate with DNA fragments demonstrable with Southern blots. In contrast, DNA typing of class II antigens is a valuable tool for reclassifying cells previously typed by anti-HLA sera. Since antisera for recently described HLA antigens are not easily available, the development of a well-characterized panel is essential for the correct screening of incoming sera. These sera, in turn, permit the accurate typing of donor-recipient pairs in kidney and bone marrow transplantation.

Blotting, Southern↗
PubMed1989

[Histopathologic aspects of hyperacute graft rejection in human cardiac transplantation. A case report].

The first case of a hyperacute rejection of a human cardiac allograft in Brazil is reported. The histopathological aspects of hyperacute cardiac rejection in its earlier moments are described when degenerative and necrotic features of the cardiac fibers are not totally developed. The authors believe that neutrophilic exudation and lesion of the vessel wall are good signs for a correct diagnosis of hyperacute rejection. Furthermore, they observed that the process is diffuse enough to justify the indication of endomyocardial biopsy when there are reasons to suspect this diagnosis. Presence of IgM and complement (C3) are also useful.

Adult↗
PubMed1984

Ia-like antigen expression on biologically different human melanoma cell lines.

Ia-like antigen binding of a large panel of monoclonal antibodies (six anti-human Ia-like monoclonal antibodies and ten murine anti-Ia monoclonal antibodies cross-reactive with human Ia-like antigens) were compared on seven permanent human melanoma cell lines by radioimmunoassay. Cell lines were initiated from primary or metastatic tumors and presented various levels of tumorigenicity (assessed by heterotransplantation in nude mice) and pigmentation (shown by 5-S-cysteinyldopa determination and cytological data). Two cell lines originated from the same primary melanoma, while two other pairs of cell lines originated from superficial spreading melanoma or metastatic lymph node of the same patients. Identical Ia-like allodeterminants were found in cell lines of the same individual origin. Quantitative expression of beta 2-microglobulin and Ia-like antigens was similar in all cell lines except for one, in which these molecules were expressed in lower amounts. These results indicate that Ia-like antigen expression of the cell lines is unrelated to primary or metastatic origin, degree of pigmentation and ability to grow in nude mice.

Adult↗
PubMed1983

Role of class I and class II antigens in the allogenic stimulation: class I and class II recognition in allogenic stimulation; blocking of MLR by monoclonal antibodies and F(ab')2 fragments.

Purified monomorphic monoclonal antibodies against Class I and Class II antigens in the inhibition of in vitro allogenic response were assayed. As expected, anti-Class II antibodies are highly inhibitory when used in concentrations greater than 5 micrograms/ml in MLRI and 50 micrograms/ml in MLRII. Surprisingly, anti-Class I monoclonal antibodies are as effective as anti-Class II in inhibiting primary MLR although they have no effect in MLRII. These results were confirmed by using F(ab')2 fragments. The inhibitory effect of anti-Class I has been shown to occur at the stimulator cell level. It is proposed that the allogenic stimulation is elicited after Class I and Class II recognition although only Class II differences are responsible for the proliferative response.

Antibodies, Monoclonal↗
PubMed1983

HLA class I genes integrated into murine cells are inducible by interferon.

In human cells treated with interferon, there is an increase in the amount of HLA-A, B, C mRNA and, to a lower extent, membrane-bound antigen. However, the mechanism of this mRNA enhancement is still unknown. Using mouse L cells transfected with a unique class I HLA gene, we were able to show that both the related HLA mRNA and protein are increased after murine but not human interferon treatment. Moreover, the discrepancy between interferon-directed HLA mRNA and protein enhancement is also observed. The mouse transfected cells allowed us to study more precisely the origin of this discrepancy.

Animals↗
PubMed1983

Expression of beta 2-microglobulin on preimplantation pig embryos.

The expression of beta-2 microglobulin (beta 2m), a protein associated with the histocompatibility antigens of the pig complex (SLA), was studied in preimplantation embryos between the segmentation stage and the beginning of elongation (day 12). The antigen was visualized at the ultrastructural level by immunocytochemical techniques using peroxidase or colloidal gold particles as labels. beta 2m expression appeared to parallel trophoblast differentiation. No positive reaction was obtained before the early blastocyst stage. From this stage on, labelling was observed on the apical surface of the trophectoderm cells.

Animals↗
PubMed1983

Expression of cell surface antigens during allogeneic response studies with monoclonal antibodies to a polymorphic marker of activated lymphocytes and HLA class I and class II antigens.

The kinetics of expression of cell surface antigens were studied during allogeneic stimulation and compared to 3H-thymidine incorporation. Two markers of T cell activation identified by monoclonal antibodies (monomorphic HLA-DR and a polymorphic blastic antigen) were compared to an ubiquitous antigen (beta 2m). beta 2m (Class I) and DR (Class II) antigens showed enhanced expression on alloactivated lymphocytes while the blastic antigen was only detected on alloactivated lymphocytes from serologically positive donors. The increased expression of these antigens could distinguish positive and negative mixed lymphocyte reactions and they preceded the rise in 3H-thymidine uptake.

Antibodies, Monoclonal↗
PubMed1983

Monoclonal antibodies to HLA recognize monomorphic and polymorphic epitopes on BoLA.

Fourteen monoclonal antibodies recognizing monomorphic and polymorphic epitopes on class I and class II antigens of the human MHC have been assayed on lymphocytes of a panel of 20-150 BoLA typed bovine animals from 12 different breeds. Some monomorphic antibodies cross-reacted and others did not. Two polymorphic monoclonal antibodies in man recognize a polymorphism in cows that follows allospecificities (BoLA-w3, w9) already described. Immunoprecipitation experiments with monomorphic anti-B2m and anti-HLA-DR monoclonal antibodies have shown that these cross-reactions concern BoLA antigens. They also revealed that Ia-like antigens in cattle present the same two chain features characterized in other species.

Animals↗
PubMed1983

Influence of HLA class I- and class II-specific monoclonal antibodies on DR-restricted lymphoproliferative responses. I. Unseparated populations of effector cells.

L1-16, a DR-specific, nonpolymorphic monoclonal antibody (MoAb) recognizing the beta-chain of the molecule, blocked virus-specific as well as allogeneic-proliferative T cell responses, whereas another nonpolymorphic anti-DR MoAb blocked proliferative responses to allogeneic cells only. IL 2-supernatants reversed the blocking induced by L1-16. On the other hand class I-specific MoAb B1-23-2 (HLA-A-B-C-specific) and M 18 (beta 2 microglobulin-specific) and their F(ab')2 fragments blocked equally virus-specific or allogeneic proliferative responses. IL 2-containing supernatants did not reverse this phenomenon. Neither anti-class I nor anti-class II MoAb inhibited the IL 2-induced proliferation of IL 2-dependent established T cell lines. MoAb acted neither at the antigen-presenting cell level nor by a toxic effect nor by inducing suppressor cells. These results suggest that a) different epitopes of the DR molecule can be involved during responses to influenza viruses and allogeneic antigens; b) the epitope recognized by L1-16 on the beta-chain of the DR molecule seem necessary for IL 2 production by lymphocytes after activation with influenza antigens; and c) class I-specific MoAb block DR-restricted proliferative responses of lymphocytes by an as yet unknown mechanism.

Adult↗
PubMed1983

Identification of a viral antigen recognized by H-2-restricted cytolytic T lymphocytes on a murine leukemia virus-induced tumor.

Monoclonal antibodies were produced against protein p30, a structural protein of murine leukemia viruses (MuLV) coded by the gag gene of MuLV. Three monoclonal antibodies of different isotypes (i.e., IgG-1, IgG-2a, and IgG-2b) were chosen for extensive analysis. These three antibodies bound to mouse tumor cells induced by Friend, Moloney, Rauscher, and Gross MuLV, but not to noninfected normal mouse spleen cells. The ability of these monoclonal antibodies to inhibit cytolytic T lymphocyte (CTL) activity by masking the antigens recognized by CTL on the target cell surface was studied in various CTL systems. It was found that the only CTL that were consistently inhibited in their lytic activity came from BALB.B (H-2b) mice immunized against syngeneic Gross MuLV-induced B.GV cells. These results thus showed that a subpopulation of BALB.B anti-Gross MuLV CTL recognized a Gross MuLV gag gene product expressed on the surface of B.GV cells.

AKR murine leukemia virus↗