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W H Barber

Publications and source records attributed to W H Barber.

52 records · Page 3Linked to original sources
PubMed1988

A comparison of OKT3 monoclonal antibody and corticosteroids in the treatment of acute renal allograft rejection.

The monoclonal antibody OKT3 (Ortho Pharmaceutical, Raritan, NJ) was utilized in two separate protocols for treatment of acute renal allograft rejection in patients receiving cyclosporine, azathioprine, and prednisone for maintenance immunosuppression. In Group I, 54 patients received steroids for primary treatment of acute rejection with OKT3 used for resistant rejections and second rejection episodes. In Group II, 34 patients received OKT3 as primary treatment of acute rejection while steroids were used for rescue and second rejection episodes. OKT3 successfully reversed 82% of initial acute rejection episodes in Group II as compared with a 63% reversal with steroids in Group I. Rescue treatment was required in only 15% of Group II patients compared with 33% of Group I patients. Overall patient survival was 96% and 94%, respectively, for steroid primary and OKT3 primary treatments. Allograft survival at 3 months was identical, 74% in both groups. Based on allograft survival data, OKT3 is equally effective either as primary treatment for allograft rejection, or for rescue therapy if initial corticosteroid treatment fails.

Acute Disease↗
PubMed1988

Important risk factors of allograft survival in cadaveric renal transplantation. A study of 426 patients.

Multiple risk factors contribute to the allograft survival of patients who have cadaveric renal transplantation. A retrospective review of 19 such factors in 426 patients identified race, DR match, B + DR match, number of transplants, and preservation time to have a significant influence. The parametric analysis confirmed the effect to be primarily in the early phase, i.e., first 6 months. All patients received cyclosporine with other methods of immunosuppression resulting in an overall 1-year graft survival rate of 66%. The overall 1-year graft survival rate in the white race was 73% and in the black race was 57% (p = 0.002). Allograft survival and DR match showed white recipients with a 1 DR match to have 75% survival at 1 year compared with 57% in the black patient (p = 0.009). If HLA B + DR match was considered, the white recipient allograft survival increased to 76%, 84%, and 88% for 1, 2, and 3 match kidneys by parametric analysis. Patients receiving first grafts had better graft survival (68%) than those undergoing retransplantation (58%) (p = 0.05). Organ preservation less than 12 hours influenced allograft survival with a 78% 1-year survival rate compared with 63% for kidneys with 12-18 hours of preservation. Despite the benefits of B + DR typing, short preservation time, and first transplants to the white recipient, the allograft survival in the black recipient remained uninfluenced by these parameters.

Adolescent↗
PubMed1987

Influence of race on renal allograft survival in the pre- and postcyclosporine era.

In conclusion we find that white cadaveric recipients of renal allografts have clearly benefited from the use of CsA. Matching for the major histocompatibility antigens, especially HLA-B + DR, is also associated with improved allograft survival in whites. For black cadaveric recipients there was no significant improvement in allograft survival with the use of CsA nor with matching for HLA. In contrast, for recipients of LRD kidneys both races appear to benefit from the use of CsA over conventional therapy. Consequently, it is clear that with the excellent allograft survival in LRD black recipients that matching can have a significant beneficial effect. However, the differences in survival between the races of cadaveric recipients suggest that for blacks the use of CsA cannot overcome the inherent genetic or physiologic differences that may exist. These results suggest that blacks should be targeted for concentrated study, the benefits of which would be to increase our understanding of potential factors influencing allograft survival in a group that comprises an increasingly larger proportion of candidates on waiting lists throughout the United States. 1. Overall renal allograft survival in CsA-treated black recipients is significantly lower than in comparable white recipients. The major period of allograft loss is in the first 6 months after which the rates of allograft loss for blacks and whites are similar. 2. There was a 12% increase in allograft survival in CsA-treated cadaveric recipients compared to pre-CsA-treated recipients. Allograft survival in white recipients has increased 15% whereas for black recipients there was only a 5% improvement over the azathioprine-prednisone treatment group. 3. Overall, there was a significantly improved graft survival for primary transplants compared to retransplants. Renal allograft survival in black CsA-treated recipients of primary transplants was significantly lower than in comparable whites, whereas there was no significant difference in graft survival between black and white recipients of retransplants. 4. Allograft survival rates in black and white recipients of kidneys from living-related donors were not significantly different from each other in either the non-CsA or the CsA immunotherapy group. 5. Overall there was improved allograft survival with increased matching for HLA-DR or B + DR compared to a zero match in CsA-treated recipients. Significantly, the effect of matching for HLA-DR or B + DR was seen only in white recipients.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1985

Specific suppression of allograft rejection by trinitrophenyl (TNP)-induced suppressor cells in recipients treated with TNP-haptenated donor alloantigens.

Suppressor T cells, activated by injection of trinitrobenzene sulphonic acid in DA rats, prevented rejection of LEW kidney allografts in a donor-specific manner when adoptively transferred into syngeneic recipients along with trinitrophenyl (TNP)-haptenated LEW alloantigen. TNP-haptenated third-party alloantigen was ineffective in this system. The donor-specific suppression was dependent, too, on the haptenic portion of the chemically modified alloantigen. Hence, fluorescein isothiocyanate-donor antigen did not lead to suppression in the presence of TNP-reactive suppressor cells. There is, however, some crossreaction between DNP- and TNP-haptenated alloantigens so that TNP-reactive cells and DNP-donor antigen suppressed rejection whereas DNP-reactive cells and TNP-donor antigen did not prevent graft rejection. The suppressor cells were sensitive to cyclophosphamide and radiation but were resistant to hydrocortisone. They appear to be T cells of the OX8 (suppressor/cytotoxic) phenotype since they are positive for the pan T cell antigen W3/13, are Ig negative, and do not carry the W3/25 (T helper cell) marker. However, these suppressor cells are adherent to nylon wool. They are found mainly in the spleen, are detected there within 2 d of TNBS injection, and can persist for up to 12 wk. We propose that these cells are first-order T suppressor (Ts1) cells that act in the afferent phase of the response to a renal allograft.

Animals↗
PubMed1983

Enhancement of rat kidney allografts using haptenated alloantigens and antihapten antibody.

The survival of semiallogeneic or fully allogeneic rat kidney allografts was prolonged in some strain combinations with immune complexes formed with hapten-conjugated alloantigens (TNP-Ag) of donor origin and a mouse monoclonal antihapten antibody (anti-TNP). Complexes were administered i.v. at the time of operation--and, in some cases, on subsequent days. Complexes using TNP-modified alloantigen in various forms--donor whole spleen lymphocytes, cellular membrane sonicate, or papain-solubilized-were all found to be effective in enhancing graft survival in specific donor-recipient combinations. Indefinite survival was obtained in some recipient groups with semiallogenic donors, and a more modest degree of enhancement was seen with fully allogeneic kidneys. The enhancing effect was shown to be donor-specific and highly dependent on the ratio of anti-TNP antibody to TNP alloantigen.

Animals↗
PubMed1980

Heterotypic immunity to influenza in ferrets.

Heterotypic immunity to influenza virus in ferrets operated against heterotypic influenza viruses but not heterologous viruses. Contrary to prior reports, the protection conferred lasted for at least 18 months. This type of immunity limited virus shedding but did not prevent infection. These results suggest that this phenomenon could play a role in determining the severity of infections caused by type A influenza viruses in humans.

Age Factors↗
PubMed1978

Local and systemic immunity to influenza infections in ferrets.

To establish whether immunity to influenza infection in the ferret is local or systemic, two sites of challenge were utilized: the nose and the anatomically isolated tracheal pouch. Infection of either site did not spread to the other site, and challenge of either site resulted in seroconversion by 13 days. Simultaneous challenge of both sites 21 days after the primary infection revealed that prior infection of the pouch prevented subsequent reinfection of the pouch, but not infection of the nose. Thus, systemic immunity did not prevent the initiation of nasal influenza infection in the ferret. However, the duration of virus shedding from the nose was reduced to half of that seen when ferrets were infected for the first time, showing that the prior pouch infection did lead to a more rapid recovery from the subsequent nasal infection. Passively administered anti-influenza antibody did not prevent or modify the nasal infection, but it did prevent the pouch infection. This is consistent with the observation that an initial infection of the nose prevented pouch infection upon challenge 21 days later. The prior nasal infection also prevented the subsequent nasal infection. These data suggest that immunity to acquisition of influenza infection in the ferret is a local phenomenon, whereas recovery from active infection is influenced by systemic immune mechanisms.

Animals↗
PubMed1974

Dissemination of influenza virus between anatomically isolated sites in ferrets.

Influenza virus was shown to disseminate from the respiratory tract of nasally infected ferrets to a surgically formed, subcutaneous tracheal pouch. Conversely, ferrets infected via the pouch shed virus from the upper respiratory tract. These events occurred within the first 24 h after infection. Passively administered ferret antibody to virus did not prevent the dissemination.

Animals↗
PubMedDate not supplied

Combined analysis of cytokine genotype polymorphism and the level of expression with allograft function in African-American renal transplant patients.

Cytokine gene polymorphism and expression levels were evaluated in a group of African-American patients who had undergone renal transplantation. It was hypothesized that possession of specific cytokine alleles might be influential in predisposing the recipient to allograft rejection. Thus, we sought to establish a relationship between cytokine gene polymorphism, the levels of cytokine expression, and the outcome of allograft function. Cytokine genotypes and mRNA transcript levels of IL-2, TNF-alpha, TGF-beta1, IL-10, IL-6 and IFN-gamma were determined using peripheral blood cells. Genomic DNA samples from 77 transplant recipients and 77 controls were tested by a multiplex PCR with specific primers for the above cytokines. The frequency distributions of cytokines were analyzed in respect to the clinical characterization, including delayed graft function (DGF), rejection episodes (REs) and stable graft function (SGF). The mRNA transcript level was tested both at pre- and early post-transplantation (day 1 and day 4) with primers for coding regions of the above cytokines in a RT-PCR assay. The majority of recipients with successful graft function were matched with their donors for only three out of the six HLA alleles. We have shown that the TGF-beta1 T/C G/G high producer and IFN-gamma T/A intermediate producer genotypes were associated with allograft rejection, whereas low IFN-gamma producer and high IL-10 producer genotypes were significantly protective of the allograft. There was some correlation between the TGF-beta1 high producer genotype and DGF, but it was not statistically significant. Overall, 77% of those who experienced REs carried the TGF-beta1 T/C G/G, high producer genotype as compared with 52% who experienced DGF, 39% with SGF (P<0.01, RR=2.0), and 27.3% of controls (P<0.003, RR=2.6). The IFN-gamma T/A intermediate producer genotype was found in 69.2% of patients with REs as compared with 26.8% of patients with SGF (P<0.008, RR=2.85). The IL-10, ATA/ATA low producer genotype was found in 38.5% of recipients with REs and 14.6% of recipients without REs (P<0.04, RR=0.53). Expression levels of mRNA transcript were correlated with genotype data, except for the TGF-beta1 high producer genotype where there was no significant difference between the level of mRNA transcript at pre- and post-transplantation. Low DRbeta1 and high DPbeta1 expression by recipient peripheral blood mononuclear cells before transplantation was associated with more SGF, whereas high DRbeta1 and low DPbeta1 expression at pretransplantation was associated with more REs (DRbeta1, P<0.001 and DPbeta1, P<0.05, respectively). We concluded that, dual analysis of cytokine genotype and expression levels by peripheral cells may be an important clue to understanding the contribution of the recipient's immune response to an allograft pre- and post-transplantation. Identification of peripheral markers diagnostic of rejection could allow advance anticipation of clinical outcome, and might reduce the need for tissue biopsy.

Black or African American↗